Category Archives: cameras

What is Dual Base ISO and why is it important?

Almost all modern day video and electronic stills cameras have the ability to change the brightness of the images they record. The most common way to achieve this is through the addition of gain or through the amplification of the signal that comes from the sensor. 

On older video cameras this amplification was expressed as dB (decibels) of gain. A brightness change of 6dB is the same as one stop of exposure or a doubling of the ISO rating. But you must understand that adding gain to raise the ISO rating of a camera is very different to actually changing the sensitivity of a camera.

The problem with increasing the amplification or adding gain to the sensor output is that when you raise the gain you increase the level of the entire signal that comes from the sensor. So, as well as increasing the levels of the desirable parts of the image, making it brighter, the extra gain also increases the amplitude of the noise, making that brighter too.

Imagine you are listening to an FM radio. The signal starts to get a bit scratchy, so in order to hear the music better you turn up the volume (increasing the gain). The music will get louder, but so too will the scratchy noise, so you may still struggle to hear the music. Changing the ISO rating of an electronic camera by adding gain is little different. When you raise the gain the picture does get brighter but the increase in noise means that the darkest things that can be seen by the camera remain hidden in the noise which has also increased in amplitude.

Another issue with adding gain to make the image brighter is that you will also normally reduce the dynamic range that you can record.

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This is because amplification makes the entire signal bigger. So bright highlights that may be recordable within the recording range of the camera at 0dB or the native ISO may be exceed the upper range of the recording format when even only a small amount of gain is added, limiting the high end.

Screenshot-2019-11-27-at-18.22.59-1024x576 What is Dual Base ISO and why is it important?
Adding gain amplifies the brighter parts of the image so they can now exceed the cameras recording range.

 

At the same time the increased noise floor masks any additional shadow information so there is little if any increase in the shadow range.

Reducing the gain doesn’t really help either as now the brightest parts of the image from the sensor are not amplified sufficiently to reach the cameras full output. Very often the recordings from a camera with -3dB or -6dB  of gain will never reach 100%.

Screenshot-2019-11-27-at-18.23.08-1024x576 What is Dual Base ISO and why is it important?
Negative gain may also reduce the cameras dynamic range.



A camera with dual base ISO’s works differently.

Instead of adding gain to increase the sensitivity of the camera a camera with a dual base ISO sensor will operate the sensor in two different sensitivity modes. This will allow you to shoot at the low sensitivity mode when you have plenty of light, avoiding the need to add lots of ND filters when you want to obtain a shallow depth of field. Then when you are short of light you can switch the camera to it’s high sensitivity mode.

When done correctly, a dual ISO camera will have the same dynamic range and colour performance in both the high and low ISO modes and only a very small difference in noise between the two.

How dual sensitivity with no loss of dynamic range is achieved is often kept very secret by the camera and sensor manufacturers. Getting good, reliable and solid information is hard. Various patents describe different methods. Based on my own research this is a simplified description of how I believe Sony achieve two completely different sensitivity ranges on both the Venice and FX9 cameras.

The image below represents a single microscopic pixel from a CMOS video sensor. There will be millions of these on a modern sensor. Light from the camera lens passes first through a micro lens and colour filter at the top of the pixel structure. From there the light hits a part of the pixel called a photodiode. The photodiode converts the photons of light into electrons of electricity. 

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Layout of a sensor pixel including the image well.

In order to measure the pixel output we have to store the electrons for the duration of the shutter period. The part of the pixel used to store the electrons is called the “image well” (in an electrical circuit diagram the image well would be represented as a capacitor and is often simply the capacitance of the the photodiode itself).

Screenshot-2019-11-27-at-17.41.00-1024x605 What is Dual Base ISO and why is it important?
The pixels image well starts to fill up and the signal output level increases.

Then as more and more light hits the pixel, the photodiode produces more electrons. These pass into the image well and the signal increases. Once we reach the end of the shutter opening period the signal in the image well is read out, empty representing black and full representing very bright.

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Consider what would happen if the image well, instead of being a single charge storage area was actually two charge storage areas and there is a way to select whether we use the combined image well storage areas or just one part of the image well.

Screenshot-2019-11-27-at-18.10.02-1024x575 What is Dual Base ISO and why is it important?
Dual ISO pixel where the size of the image well can be altered.

When both areas are connected to the pixel the combined capacity is large. So it will take more electrons to fill it up, so more light is needed to produce the increased amount of electrons. This is the low sensitivity mode. 

If part of the charge storage area is disconnected and all of the photodiodes output is directed into the remaining, now smaller storage area then it will fill up faster, producing a bigger signal more quickly. This is the high sensitivity mode.

What about noise?

In the low sensitivity mode with the bigger storage area any unwanted noise generated by the photodiode will be more diluted by the greater volume of electrons, so noise will be low. When the size of the storage area or image well is reduced the noise from the photodiode will be less diluted so the noise will be a little bit higher. But overall the noise will be much less that that which would be seen if a large amount of extra gain was added.

Note for the more technical amongst you: Strictly speaking the image well starts full. Electrons have a negative charge so as more electrons are added the signal in the image well is reduced until maximum brightness output is achieved when the image well is empty!!

As well as what I have illustrated above there may be other things going on such as changes to the amplifiers that boost the pixels output before it is passed to the converters that convert the pixel output from an analog signal to a digital one. But hopefully this will help explain why dual base ISO is very different to the conventional gain changes used to give electronic cameras a wide range of different ISO rating.

On the Sony Venice and the PXW-FX9 there is only a very small difference between the noise levels when you switch from the low base ISO to the high one. This means that you can pick and choose between either base sensitivity level depending on the type of scene you are shooting without having to worry about the image becoming unusable due to noise.

NOTE: This article is my own work and was prepared without any input from Sony. I believe that the dual ISO process illustrated above is at the core of how Sony achieve two different base sensitivities on the Venice and FX9 cameras. However I can not categorically guarantee this to be correct.

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More about S-Cinetone and the so called Venice Color Science.

UPDATED WITH NEW INFO, Nov 23rd 2019.

What is the “Venice Look”?

Sony had often been criticized for having a default look to their cameras that wasn’t “film like”. This was no accident as Sony have been a leading producer of TV cameras for decades and a key thing for a broadcaster is that both old and new cameras should match. So for a very long time all of Sony’s cameras were designed to look pretty much like any other TV camera.

But this TV look wasn’t helping Sony to sell their film style cameras. So when they developed the image processing for the Venice camera a lot of research was done into what makes a pretty picture. Then over a period of about 18 months a new LUT was created for the Venice camera to take advantage of that sensors improved image quality and to turn the output into a beautiful looking image. This LUT was designed to still leave a little room to grade so is slightly flat. But it does include a big highlight roll off to help reserve a lot of the cameras dynamic range.

This LUT  is called s709 (I think it simply stands for “Sony 709) and it’s a large part of the reason why, out of the box, the Venice camera looks the way it does. Of course a skilled colourist might only rarely use this LUT and may make the output from a Venice look very different, but a Venice with s709 is regarded as the default “Venice look”, and it’s a look that a lot of people really, really like. It’s what comes out of the SDI ports, is what’s seen in the viewfinder and can be recorded to the SxS cards unless you select the legacy 709(800) LUT. s709 is the LUT applied by default to X-OCN from Venice by default. 

What is Color Science

Colour Science is the new fancy term that Red have turned into a catch-all for anything to do with colour and it’s now much abused.  Every color video camera ever made uses color science to determine the way the image looks. it’s nothing new. All colour science is, is how all the different elements of a camera and it’s workflow work to produce the final colour image. But in the last couple of years it seems to have become to mean “color magic” or “special sauce”.

If we are to be totally accurate the only camera with Venice colour science is Venice. No other camera has exactly the same combination of optical filters, sensor, processing, codecs and workflow. No other camera will replicate exactly the way Venice responds to light and turns it into a color image. You might be able to make the output of another camera appear similar to a Venice, but even then it won’t be the same colour science. What it would be is perhaps the “Venice look”.

The FS5 II and it’s new default look.

So when Sony released the FS5 II they were very careful to describe the default mode as providing a Venice “like” image, tuned to provide softer, alluring skin tones using insight and expertise gained during the development of Venice.  Because that’s what it is, it looks more like Venice than previous generations of Sony cameras because it has been tuned to output a image that looks similar. But it isn’t really Venice color science, it’s a Venice look-a-like or at least as similar as you can get, even though it’s a very different sensor, but with a touch of extra contrast added to make it more suitable for an out of the box look that won’t necessarily be graded.

And the PXW-FX9 and s-Cinetone?

The FX9  has new colour filters, a new sensor, new processing. But it is not a Venice. In Custom mode it has what Sony are now calling “S-Cinetone” which is set to become their new default look for their film style cameras. This once again is based on the Venice look and shares many similarities to the Venice colour science, but it will never be the full Venice colour science because it can’t be, it’s different hardware. But it sure as hell looks pretty damn close to a Venice at it’s default settings with the default s709 LUT applied. S-Cinetone is a combination of a gamma curve called “original” and a matrix called “S-Cinetone” in the FX9. When used together S-Cinetone gives the same colours as Venice and similar gamma, but with slightly increased contrast suitable for direct-to-air applications where the material won’t be graded (s709 in comparison is a touch flatter). If you want you can mix different gamma curves with the S-Cinetone matrix to have the Venice like colours but with different contrast ranges to suit the scene that you are shooting. If you need a broadcast safe image you can use Hypergamma1 with the S-Cinetone matrix.

Is the Venice look always there?

Previous generations of Sony cameras used a common default 709 gamma often denoted as STD5. This is what most of us probably called the “Sony look”. The exact colour science in each camera with this look would have been quite different as there were many combinations of filters, sensors and processing, but those variations in processing were designed such that the final output of generations of Sony TV cameras all looked almost exactly the same. This too still exists in the FX9 and when set to STD5 the FX9 will produce an image very, very close to earlier generations of Sony camera. But from this new sensor with the latest filters etc. so even with the latest sensor and latest colour filters you can still have the old look. This just demonstrates how the broad brush use of the term colour science is so confusing as the FX9 is a new camera with new colour science, but it can still look just like the older cameras.

What about when I shoot S-Log3?

When shooting S-Log3 with the FX9, then you are shooting S-Log3. And S-Log3/S-Gamut3 )or S-gamut3.cine) is a set standard where certain numerical values represent certain real world colours and brightnesses. So the S-Log3 from an FX9 will look very similar to the S-Log3 from a Venice, which is similar to the S-Log3 from a F55 which is similar to the S-Log3 from an FS7.

But compared to an FS7 at least, the different, improved sensor in the FX9 will mean that it will be able to capture a bigger dynamic range, it will have less noise and the sensors response to colour will be different. BUT it will still be recorded in the same manner using the same gamma curve and colour space with the same numerical values representing the same brightness levels and colours. However the fact that the sensor is different will mean there will be subtle differences within the image. One obvious one being the extra dynamic range, but also things like better colour separation and more true to life color response at the sensor level.

Then you apply the s709 LUT, the very same LUT as used for Venice. So those very same numerical values are turned into the same expected colours and brightness levels. But because it’s a different sensor some values may have been better captured, some worse, so while overall the image will look very, very similar there will be subtle differences, it’s the subtle differences that make one look more natural or more pleasing than the other.  For example the FX9 image will have less noise and greater DR than the image from and FS7. In addition the FX9 images will have more pleasing looking skin tones because from what I have seen the sensor responds better to the tones that make up a face etc.

why not use the same name for s709 and S-cinetone?

S-Cinetone is different to s709. One is a gamma curve plus colour matrix designed to be recorded as is. You can’t change middle grey or white, you can’t alter the highlight or shadow ranges, other than by using alternate gammas with the S-Cinetone matrix. The default “original” gamma curve has a touch more contrast than the S-Log3 + s709 LUT.

s709 is a LUT applied to S-Log3 material which gives you the ability to alter your highlight and shadow ranges, to move the mid point. Both will look very, very similar, but they are two different things that require two very different workflows, to call them the same thing would be confusing. You get a call from the producer “I want you to shoot S-Cinetone”…. Which one? The log one or the S-Cinetone one?

Because the FX9’s optical low pass filter, ND filter, sensor colour filters, pixels, sensor output circuits and initial processing of the image are all the same whether in S-Cinetone or S-Log3, then those aspects of the colour science are common for both. But when shooting s-Log3 you have a huge range of options in post, not just s709.

So in reality the FX9 has several different color sciences. One that mimics a default Venice camera without needing to shoot log and grade. One that mimics earlier generations of sony TV cameras. Another that mimics a Sony Venice when shooting S-Log3 and using the s709 LUT.

The PXW-FX9 in the real world.

There are already a few setup and staged video samples from the new Sony PXW-FX9 circulating on the web. These are great. But how will it perform and what will the pictures look like for an unscripted, unprepared shoot? How well will the autofocus work out in the street, by day and by night? How does the S-Cinetone gamma and colour in custom mode compare with S-Log3 and the s709 Venice LUT compare?

To answer these questions I took a pre-production FX9 into the nearby town of Windsor with a couple of cheap Sony E-Mount lenses. The lenses were the Sony 50mm f1.8 which costs around $350 USD and the 28-70mm f3.5-f5.6 zoom that costs about $400 USD and is often bundled as a kit lens with some of the A7 series cameras.

To find out how good the auto focus really is I decided to shoot entirely using auto focus with the AF set to face priority. The only shot in the video where AF was not used is the 120fps slow-mo shot of the swans at 0:53 as AF does not work at 120fps.

Within the video there are examples of both S-Cinetone and S-Log3 plus the s709 LUT. So you know which is which I have indicated this is the video. I needed to do this as the two cut together really well. There is no grading as such. The S-Cinetone content is exactly as it came from the camera. The CineEI S-Log3 material was shot at the indicated base ISO and EI, there was no exposure offset. In post production all I did was add the s709 LUT, that’s it, no other corrections.

The video was shot using the Full Frame 6K scan, recording to UHD XAVC-I.

For exposure I used the cameras built in waveform display. When in CineEI I also used the Viewfinder Gamma Display assist function. Viewfinder Gamma assist gives the viewfinder the same look as the 709(800) LUT. What’s great about this is that it works in all modes and at all frame rates. So even when I switched to 2K Full Frame scan and 120fps the look of the image in the viewfinder remained the same and this allowed me to get a great exposure match for the slow motion footage to the normal speed footage. 

AUTOFOCUS.

There are some great examples of the way the autofocus works throughout the video. In particular the shot at 0:18 where the face priority mode follows the first two girls that are walking towards the camera, then as they exit the frame switches to the two ladies following behind without any hunting. I could not have done that any better myself. Another great example is at 1:11 where the focus tracks the couple walking towards the camera and once they exit the shot the focus smoothly transitions to the background. One of the nice things about the AF system is you can adjust the speed at which the camera re-focusses and in this case I had slowed it down a bit to give it a more “human” feel.

Even in low light the AF works superbly well. At 1:33 I started on the glass of the ornate arch above the railway station and panned down as two people are walking towards me. The camera took this completely in it’s stride doing a lovely job of shifting the focus from the arch to the two men. Again, I really don’t think I could have done this any better myself.

NOISE.

Also, I am still really impressed by how little noise there is from this camera. Even in the high ISO mode the camera remains clean and the images look great. The low noise levels help the camera to resolve colour and details right down into the deepest shadows. Observe how at 2:06 you can clearly see the different hues of the red roses against the red leather of the car door, even though this is a very dark shot.

The reduction in noise and increase in real sensitivity also helps the super slow motion. Compared to an FS7 I think the 120fps footage from the FX9 looks much better. It seems to be less coarse and less grainy. There is still some aliasing which is unavoidable if you scan the sensor at a lower resolution, but it all looks much better controlled than similar material from an FS7.

DYNAMIC RANGE.

And when there is more light the camera handles this very well too.  At 1:07 you can see how well S-Cinetone deals with a very high contrast scene. There are lots of details in the shadows and even though the highlights on the boats are clipped, the way the camera reaches the end of it’s range is very nice and it doesn’t look nasty, it just looks very bright, which it was.

For me the big take-away from this simple shoot was just how easy it is to get good looking images. There was no grading, no messing around trying to get nice skintones. The focus is precise and it doesn’t hunt.  The low noise and high sensitivity means you can get good looking shots in most situations. I’m really looking forward to getting my own FX9 as it’s going to make life just that little bit easier for many of my more adventurous shoots.

For more information on the PXW-FX9 click here. 

Or take a look at the Sony website.

External Recording Options On The FX9.

There are a lot of people discussing the raw output option for the FX9. In particular the need to use the XDCA-FX9 adapter. First I do understand where those that think the XDCA is big, bulky and ugly are coming from. It certainly won’t win any design awards! And I also understand that we would all probably prefer to have the raw out direct from the camera body, but that’s not going to happen.

Besides which, the raw option won’t get enabled until some time next year in a firmware update. So in the meantime what are the alternatives?

Up to 30fps the FX9 can output UHD in 10 bit 4:2:2 over HDMI. At 60fps I’m led to believe that you can output 10 bit 4:2:2 UHD over the 12G SDI, but I have yet to actually test this.  The ability to output 30fps UHD over SDI requires 6G SDI and the standards for 6G SDI are still all over the place, but once the standards settle I am led to believe that 6G SDI should be added via a firmware update.

What this means is that it will be possible to output 10 bit 4:2:2 to an external recorder from launch at 24fps all the way to 60fps using either HDMI, SDI or a combination of the two. So I will be looking at using an Atomos Ninja V with the AtomX 12G SDI adapter to record the 10 bit output using ProResHQ for those projects where I really want to squeeze every last bit of image quality out of the camera.

Don’t get me wrong, XAVC-I is a great codec, especially if you want compact files, but ProRes HQ will give me just a tiny bit less compression for those really demanding projects that I get involved in (for example shooting demo content for some of the TV manufacturers).

DSC_0281-1024x576 External Recording Options On The FX9.
Atomos Ninja V on an A6300. This diminutive little recorder will be a great option for conventional video recording from the FX9

 

10 bit S-Log3 is very gradable. Because the FX9 has much less noise than the F5, FS7 or FS5 there will be no need to offset the exposure as I feel that you need to do with those cameras. So ProResHQ from an FX9 will be very, very nice to work with and the Ninja V is small, compact and uses less power than the larger Shogun models, great for when I will be travelling with the camera.

So while the camera won’t have raw for a while and perhaps even when the raw option does become available there are other ways to get some really great, highly gradable material from the FX9. Internal XAVC being one, but if you need ProRes you have some good options.

So What Does the XDCA-FX9 add?

I do suspect that the XDCA-FX9 is more than just a pass through for the raw data from the camera to the raw out SDI. To get 16 bit raw out of a camera is far more challenging than the 12 bit that the FS7 and FS5 produce. There must be some clever processing going on somewhere to squeeze 16 bit raw down a single SDI cable and I suspect that processing will be done in the XDCA-FX9 unit. The XDCA-FX9 obviously does contain a lot of processing power as it has it’s own fan cooling system. It does help balance the camera and the FX9 with XDCA-FX9 and a V-lock battery does sit very nicely on your shoulder.

In addition the XDCA adds a whole host of streaming and internet connectivity functions allowing the FX9 to be used for live news via 4G dongles without the need for a Live-U or satellite truck. Plus it has  handy switched D-Tap and Hirose power outputs.

I do look forward to getting an XDCA-FX9 for my FX9 and look forward to the raw being enabled. But even so there will also be many cases where I suspect the convenience of the compact Ninja V with the AtomX SDI adapter will be the perfect fit. It’s always good to have multiple options.

Just to make it clear – The Ninja V cannot and almost certainly never will be able to record raw from an FS5/FS7 or FX9, only conventional component video.

Can You Shoot Anamorphic with the PXW-FX9?

The simple answer as to whether you can shoot anamorphic on the FX9 or not, is no, you can’t. The FX9 certainly to start with, will not have an anamorphic mode and it’s unknown whether it ever will. I certainly wouldn’t count on it ever getting one (but who knows, perhaps if we keep asking for it we will get it).

But just because a camera doesn’t have a dedicated anamorphic mode it doesn’t mean you can’t shoot anamorphic. The main thing you won’t have is de-squeeze. So the image will be distorted and stretched in the viewfinder. But most external monitors now have anamorphic de-squeeze so this is not a huge deal and easy enough to work around.

1.3x or 2x Anamorphic?

With a 16:9 or 17:9 camera you can use 1.3x anamorphic lenses to get a 2:39 final image. So the FX9, like most 16:9 cameras will be suitable for use with 1.3x anamorphic lenses out of the box.

But for the full anamorphic effect you really want to shoot with 2x  anamorphic lenses. A 2x anamorphic lens will give your footage a much more interesting look than a 1.3x anamorphic. But if you want to reproduce the classic 2:39 aspect ratio normally associated with anamorphic lenses and 35mm film then you need a 4:3 sensor rather than a 16:9 one – or do you?

Anamorphic on the PMW-F5 and F55.

It’s worth looking at shooting 2x Anamorphic on the Sony F5 and F55 cameras. These cameras have 17:9 sensors, so they are not ideal for 2x Anamorphic. However the cameras do have a dedicated Anamorphic mode. When shooting with a 2x Anamorphic lens because the 17:9 F55 sensor, like most super 35mm sensors, is not tall enough, after de-squeezing you will end up with a very narrow 3.55:1 aspect ratio. To avoid this very narrow final aspect ratio, once you have de-squeezed the image you need to crop  the sides of the image by around 0.7x and then expand the cropped image to fill the frame. This not only reduces the resolution of the final output but also the usable field of view. But even with the resolution reduction as a result of the crop and zoom it was still argued that because the F55 starts from a 4K sensor that this was roughly the equivalent of Arri’s open gate 3.4K. However the loss of field of view still presents a problem for many productions.

What if I have Full Frame 16:9?

The FX9 has a 6K full frame sensor and a full frame sensor is bigger, not just wider but most importantly it’s taller than s35mm. Tall enough for use with a 2x s35 anamorphic lens! The FX9 sensor is approx 34mm wide and 19mm tall in FF6K mode.

In comparison the Arri  35mm 4:3 open gate sensor is area is 28mm x 18.1mm and we know this works very well with 2x Anamorphic lenses as this mimics the size of a full size 35mm cine film frame. The important bit here is the height – 18.1mm with the Arri open gate and 18.8mm for the FX9 in Full Frame Scan Mode.

FX9-Image-circle-frame-lines1 Can You Shoot Anamorphic with the PXW-FX9?
Sensor sizes and Anamorphic coverage.

Crunching the numbers.

If you do the maths – Start with the FX9 in FF mode and use a s35mm 2x anamorphic lens. 

Because the image is 6K subsampled to 4K the resulting recording will have 4K resolution.

But you will need to crop the sides of the final recording by roughly 30% to remove the left/right vignette caused by using an anamorphic lens designed for 35mm movie film (the exact amount of crop will depend on the lens). This then results in a 2.8K ish resolution image depending on how much you need to crop.

4K Bayer doesn’t won’t give 4K resolution.

That doesn’t seem very good until you consider that a 4K 4:3 bayer sensor would only yield about 2.8K resolution anyway.

Arri’s s35mm cameras are open gate 3.2K bayer sensors so will result in an even lower resolution image, perhaps around 2.2K. Do remember that the original Arri ALEV sensor was designed when 2K was the norm for the cinema and HD TV was still new. The Arri super 35 cameras were for a long time the gold standard for Anamorphic because their sensor size and shape matches the size and shape of a full size 35mm movie film frame. But now cameras like Sony’s Venice that can shoot both 6K and 4K 4:3 and 6:5 are starting now taking over.

The FX9 in Full Frame scan mode will produce a great looking image with a 2x anamorphic lens without losing any of the field of view. The horizontal resolution won’t be 4K due to the left and right edge crop required, but the horizontal resolution should be higher than you would get from a 4K 16:9 sensor or a 3.2K 4:3 sensor. Unlike using a 16:9 4K sensor where both the horizontal and vertical resolution are compromised the FX9’s vertical resolution will be 4K and that’s important.

What about Netflix?

While Netflix normally insist on a minimum of a sensor with 4K of pixels horizontally for capture, they are permitting sensors with lower horizontal pixel counts to be used for anamorphic capture. Because the increased sensor height needed for 2x anamorphic means that there are more pixels vertically. The total usable pixel count when using the Arri LF with a typical 35mm 2x anamorphic lens is 3148 x 2636 pixels. Thats a total of  8 megapixels which is similar to the 8 megapixel total pixel count of a 4K 16:9 sensor with a spherical lens.  The argument is that the total captured picture information is similar for both, so both should be, and are indeed allowed. The Arri format does lead to a final aspect ratio slightly wider than 2:39.

FX9-Image-circle-frame-lines2 Can You Shoot Anamorphic with the PXW-FX9?
Alexa LF v FX9 and super 35mm 2x anamorphic.

 

So could the FX9 get Netflix approval for 2x Anamorphic?

The FX9’s sensor has is 3168 pixel tall when shooting FF 16:9  as it’s pixel pitch is finer than the Arri LF sensor.  When working with a 2x anamorphic super 35mm lens the image circle from the lens will cover around 4K x 3K of pixels, a total of 12 megapixels on the sensor when it’s operating in the 6K Full Frame scan mode. But then the FX9 will internally down scale this to that vignetted 4K recording that needs to be cropped.

6K down to 4K means that the 4K covered by the lens becomes roughly 2.7K. But then the 3.1K from the Arri when debayered will more than likely be even less than this, perhaps only 2.1K

But whether Netflix will accept the in camera down conversion is a very big question. The maths indicates that the resolution of the final output of the FX9 would be greater than that of the LF, even taking the necessary crop into account. But this would need to be tested and verified in practice. If the math is right, I see no reason why the FX9 won’t be able to meet Netflix’s minimum requirements for 2x anamorphic production. If this is a workflow you wish to pursue I would recommend taking the 10 bit 4:2:2 HDMI out to a ProRes recorder and record using the best codec you can until the FX9 gains the ability to output raw. Meeting the Netflix standard is speculation on my part, perhaps it never will get accepted for anamorphic, but to answer the original question –

 – Can you shoot anamorphic with the FX9 – Absolutely, yes you can and the end result should be pretty good. But you’ll have to put up with a distorted image with the supplied viewfinder (for now at least).

Thinking about new lenses for the FX9?

DSC_0421-2-1024x576 Thinking about new lenses for the FX9?
Sony 28-135mm f4 zoom on the PXW-FX9

If you are starting to think about lenses to take advantage of the FX9’s amazing autofocus capabilities then you should know that I have tested quite a few different lenses on the FX9 now. I have yet to find a Sony lens where the AF hasn’t worked really well. Even the low cost Sony 50mm f1.8 and 28mm f2 lenses worked very well. Infact I actually quite like both of these lenses and they represent great value for the money.

But what I have found is that non Sony lenses have not worked well. I have been testing a range of lenses on various pre-production cameras. Maybe this situation will improve through firmware updates, I would hope so, but I honestly don’t know. The E-mount Sigma 18-35 and 20mm art lenses I tried were not at all satisfactory. The AF worked, but in what appears to be a contrast only mode. The autofocus was much slower and hunted compared to the fast, hunt free AF with the Sony lenses. You would not want to use this which is a great shame as these lenses are optically very nice.

It’s the same story when using Canon EF lenses via both Metabones and Viltrox adapters (I have not tested the Sigma MC11). Phase AF does not appear to work, only contrast and it’s slow.

So if you are thinking about buying lenses for the FX9 the only lenses I can recommend right now are Sony lenses. Don’t (at this stage at least) buy other brand E-mount lenses or expect lenses to be used via adapters unless you can find a way to test them on an FX9 first.

PXW-FX9 Base differences

While going through my photos of the FX9 from IBC I came across this one of the cameras underside. I’m posting it because I think it helps underlines the fact that Sony clearly learnt a lot from the FS7 and other earlier cameras. It also I think shows how the PXW-FX9 is designed to be a step above the FS7.

While all the small screw and the shape of the bottom of the camera is almost exactly the same as an FS7 (so existing base plates etc can be used), the screws that secure the tripod fixing plate to the camera have been seriously upgraded. Instead of little tiny screws there are now 8 cap head bolts securing the plate to the cameras chassis.

DSC_0464-2-1024x576 PXW-FX9 Base differences
The base of the Sony PXW-FX9

This is clearly going to be stronger than the small screws on the FS7 and is a welcome upgrade. So much of the FX9 has been upgraded over the FS7 that it really is a very different camera and it feels much more substantial when you hold it. The image below is a picture of the FX9’s new magnesium alloy chassis.

DSC_0352-1024x576 PXW-FX9 Base differences
The Chassis of the PXW-FX9

My take on the PXW-FX9

DSC_0385-2-1024x576 My take on the PXW-FX9
The new Sony PXW-FX9

So I’m sure you are by now aware that Sony have just launched a new camera, the PXW-FX9. I’m not going to repeat all the information that’s already in the press release or on the Sony website.

 

But instead I’m going to reflect a bit on what it’s actually like to work with, having been privileged enough to have spent a fair bit of time with various pre-production FX9’s (originally it was going to be all black and not the metallic grey that the production units will be).

Let’s be quite clear. The FX9 is not a souped up FS7 II. Although on the outside it may look similar, under the hood it is very, very different. For a start the full frame 6K sensor in the FX9 is completely new, designed specifically for this camera. What I find interesting about the sensor is that although the camera can’t do anamorphic and can only currently do 16:9 UHD (17:9 4K DCI will come in a later firmware update) it is a full height 4:3 sensor and it isn’t masked. So just maybe, anamorphic or other aspect ratios will be possible in the future. Talking to the engineers, anamorphic isn’t on the official road map, but it’s not a closed door.

DSC_0430-2-e1568982363938-1024x576 My take on the PXW-FX9
The PXW-FX9’s sensor

 

My first thought was that the decision down sample from the full frame 6K to UHD and later 4K DCI is a little disappointing, as I am sure we would all love to have the ability to record in 6K as an option. But on the other, the way the down sampling helps to clean up the sensor output, reducing noise is very welcome.

You also have to remember that a camera like the FS7 that uses a 4K bayer sensor will not be producing an image with 4K resolution. Because of the way bayer sensors work, a 4K bayer sensor will result in a recording with luma resolution around 3K depending on what you are shooting. The chrom resolution will be even less than that. But start with a 6K sensor and the 4K recordings will actually be 4K resolution with better color resolution than possible form a 4K sensor. So the images from the FX9 do look sharper and have greater clarity than those from an FS7 because they are higher resolution. But the file size is exactly the same. No need to change your workflow, no need to store bigger files, but you have more recorded resolution and better color. Great for chroma key etc.

DSC_0421-2-1024x576 My take on the PXW-FX9
Side view of the PXW-FX9

Perhaps one of the most striking differences in image quality between the FS7 and the FX9 is the lack of noise. When shooting S-Log3 the FX9 has much less noise at 4000 ISO than the FS7 at 2000 ISO. At 800 ISO the FX9 is just a little bit better again. There is less fixed pattern noise and less noise in the shadow areas. In practice what this means is that there is no need to offset the exposure when shooting log with the FX9 as there often is with the FS7. Like any camera using log you never want to be under exposed, but the FX9 works great at either of its base ISO for log producing clean largely noise free images.

DSC_0406-2-1024x576 My take on the PXW-FX9
The PXW-FX9 has 4 audio control dials.


This is a big deal because the FX9 also has a huge dynamic range, I’ve measured well over 14 stops using a DSC Xyla test chart and am not going to argue with Sony’s 15+ stop claim. I counted 16 steps on the chart from the FX9, but how useable the bottom 2 are is open to some debate. The FS7 only exhibited 14 steps when we measured the two cameras side by side and the difference between the 2 was clear to see, including all the extra noise in the FS7 images. In practice the combination of this huge dynamic range and low noise level means you get a greater usable highlight range than the FS7, FS5 or F5/F55 and you still retain an amazing shadow range. There’s no S-Log2 in the FX9 as S-Log2 can’t capture the cameras full dynamic range.

With the camera dealing so well with very big brightness and contrast ranges, what about color? While it’s possible to make almost any log camera look almost any way you wish, the question becomes – how easy is it to make it look nice? I’ve shoot quite a few short films with Sony’s Venice camera over the last 18 months and the footage from Venice is easy to work with, it’s hard to get it wrong with Venice. The FX9 is very, very similar. Straight out of the camera skin tones look good and contain lots of subtle texture and detail. When you use the s709 LUT highlights roll off in a pleasing, smooth manner. If you are given a choice between an FS7 and FX9 it will be an easy decision because the FX9 material is easier to work with in the grading suite. Take footage from the FX9 into ACES and it looks beautiful without any LUT or other correction.

DSC_0413-2-1024x576 My take on the PXW-FX9
The FX9 has a large multifunction dial for menu navigation or iris/ND control. It’s right at the front of the camera body, easy to find, easy to operate.


One thing that really helps this is the ability to dial in any white balance you want, along with a tint shift, in the CineEI mode.

So far I have only been working with the class 300 XAVC files from the FX9. As many of my readers will know I am a big fan of 16 bit raw. So I am very excited about what this camera will be capable of delivering in the future when the 16 bit raw output is implemented. I think there is a bit of a question over “can you really call 6K down sampled to 4K raw – raw”? But, I think that provided it is still essentially the same data as produced by the sensor, just re-scaled, then yes, it is a kind of raw and it should bring amazing post production flexibility, provided it can be recorded in such a way that the file sizes remain manageable. Atomos have already announced that their Neon image processor is capable of handling the 16 bit raw at 4K and 120fps. So my guess would be that by the time the firmware updated needed to enable the raw becomes available there will be an affordable Shogun Neon recorder. Some have asked – what about using the R7 and X-OCN? Well that would be cool, but how many FX9 buyers want to spend $14K for an R7 with a couple of cards and a reader? Oh – hurry up Sony and Atomos – I want 16 bit, Full Frame, 120fps 4K now, not next year 🙂

DSC_0417-2-1024x576 My take on the PXW-FX9
The FX9 has a switche for preset white balance, but you can dial in any white balance you want in custom and CineEI.

One small down side of having to read out almost twice as many pixels when reading the sensor at 6K instead of 4K is that there is a bit more rolling shutter when using the 6K full frame mode. Of course nobody likes or wants this, me included. It isn’t terrible, the camera is still very usable in 6K, but you should be aware of it for any rapid pans or large amounts of horizontal motion. In the 4K super 35mm mode the rolling shutter is similar to the current FS7/F5 etc. The other restriction is the upper limit of 30fps in the 6K full frame mode. To address this, in a later firmware update, a 5K mode which uses 83% of the full frame sensor, half way between super 35mm and full frame, will be added. This will go up to 60fps when recording to UHD. I do like the fact that you can use the full frame readout for HD at up to 120fps. There is some pixel binning when in S&Q, but it looks like it’s being done really well and I’ve only really noticed artifacts on very bright specular highlights (and this is on pre-production cameras). More testing will be needed to see just how good this is. It certainly isn’t grainy like the FS7 is in S&Q.

Once again we see Sony’s variable ND filter system. This is the biggest variable filter they have done. When the ND filter isn’t engaged there is now an extra optical flat glass included between the lens and sensor to maintain a completely constant back focus distance.  Because the sensor is attached to the variable ND filter system and fitted with a heatsink to maintain a constant temperature it isn’t possible to use IBIS as the assembly would be too heavy to move fast enough to compensate for motion. Instead The FX9 has a metadata system that will use the cameras built in motion sensors to record the cameras motion. Then you will be able to use this metadata to stabilise your footage in post production. This will work in Catalyst Browse from the day the camera becomes available for sale and Sony are working with Adobe etc to have plugins available for the major NLE’s soon after. 

DSC_0424-2-1024x576 My take on the PXW-FX9
Improved menu layout in the FX9


Even though the post production stabilization (which will be variable) needs to zoom into the image a bit, again it’s worth noting that because the full frame mode results in a recording with 4K higher resolution than say an F5 or FS7, even after the zoom in, the image still has higher resolution and better detail than most 4K bayer can deliver.

Talking of Catalyst Browse, there will also be a new version of Content Browser mobile for the FX9 that will allow you to remotely control the camera over wifi, better still the camera will provide a live video feed over the wifi link for monitoring on your phone or tablet. The latency isn’t terrible, around 4 frames. The camera body has wifi built in, no more need to add a dongle. If you want to stream over 4G or 5G then the new extension unit has a pair of USB ports for 2 mobile network dongles.

Ergonomically there have been some big improvements over the FS7. There are now many different ways to control the menu system (which is now laid out more like the Venice camera than the FS7). There is the joystick on the handgrip (which is now shaped more like the FS5 handgrip). There is a set of up/down, left/right, select push buttons on the side of the camera as well as my favourite which is a big jog dial knob that protrudes slightly from the front of the camera (ENG cameras used to have a knob like this and ot was great on them). This is just about big enough to be operated when wearing gloves.

Another improvement is the use of illuminated buttons for the buttons that select the various auto modes. When you select an auto function, such as auto gain, a light comes on to let you know it’s set to auto. Furthermore, you now have to press the button for a about 3 seconds to get it to switch into auto. This should help prevent accidental button bumps from putting the camera into a mode you don’t want to be in.

DSC_0416-2-1024x576 My take on the PXW-FX9
FX9 buttons illuminate to indicate auto operation.


There’s no shortage of user assignable buttons on the FX9. Perhaps too many? The camera really is covered in buttons! But that does mean you can do some nice things like assign the high/low ISO range change to one of the buttons to switch instantly between base ISO’s.

The great news for those that shoot using CineEI and log is that LUT’s are available in S&Q when recording UHD up to 60fps. The bad news is that above 60fps, when you have to record at HD you can’t separate the LUT between monitor LUT and baking it in. However all is not lost because the camera has viewfinder gamma assist. This applies a vanilla Rec-709 LUT to the viewfinder. It’s only going to be on the viewfinder and it doesn’t change of you change the EI, but at least you don’t have to look at the S-Log image, you can still look at a correct 709 image. Given that because of it’s much lower noise levels I don’t feel that this camera needs the exposure offsets that the FS7 needs, this is not too bad a compromise. Most of the time you will be able to shoot at 800ISO/800EI or 4000ISO/4000EI, so the viewfinder gamma assist LUT will do the job – look in the viewfinder – if it looks right, it probably is right. Oh – and in addition, the S&Q HFR is much less noisy than from the FS7.

Another thing that will make S-Log3 shooters very happy is the ability to change the white balance beyond the 3 built in presets. You can dial in whatever white balance you want including a tint adjustment, just like Venice. You can also use a white or grey card to automatically set the white balance when shooting log. So getting rid of a green cast from dodgy LED lights will be much easier.

Then there’s the autofocus.

Damn you Sony – now I’m going to have to buy some new lenses! I have to admit, I have always looked down on autofocus as an inferior way to focus a video camera. Largely because I have never had a camera where the autofocus has worked as well as I would like. Sony’s  little PXW-Z90 does have a very impressive autofocus system, but with a smaller sensor that is easier to do. Canon have pretty good autofocus on some of their cameras too. But the FX9 has me rethinking how I will approach focus for many shoots. It really is incredibly impressive. It is a hybrid phase and contrast based system that has phase detection sites across almost the entire sensor. It has been designed specifically for video. It has eye detection and face recognition, so you can tell exactly which face in a crowd you want it to focus on. It doesn’t hunt, it just locks on and holds focus. It’s also fully programmable so you can adjust the hold and release sensitivity as well as the focus shift speed. This allows you to make the way the auto focus works look like it’s being done by a human. Often autofocus is too fast, too snappy. You can have that too if you want, but having the ability to slow it down a touch really helps it feel much more natural.

For so many applications this amazing autofocus system is going to be a godsend. Gimbal and Stedicam users will benefit for a start. Anyone shooting fast moving people will benefit. I can see it being a huge help for me when shooting up in the arctic with bulky gloves and mittens or a fogged up and frozen viewfinder! I can see the FX9 finding a place on big budget movie shoots for shots where conventional focus method would otherwise prove challenging. But, you will need Sony E-Mount lenses to get the very best out of it, hence in part why Sony are also releasing new E-mount cine style lenses.

One more note: The camera does have genlock and timecode in/out – on the camera body. You don’t need the extension unit for TC in and out.

DSC_0401-2-1024x576 My take on the PXW-FX9
PXW-FX9 Timecode and genlock are now on the camera body.


In case you haven’t realised by now, I am quite excited by the FX9. It ticks a lot of boxes. You get a state of the art full frame sensor with 15 stops of dynamic range. You have dual base ISO’s of 800 and 4000. You get Venice like color science. So the images look beautiful right out of the camera. Less noise means no need to offset your exposure so you can record more highlight information and shooting is easier. You retain E-Mount versatility, once again you can put just about any lens you want on the camera via low cost adapters. But now in addition you also get an amazing, truly useful autofocus system.

No change on the codec front or media, so that keeps life simple. But 16 bit raw in the future for what should be amazing image quality and post production flexibility (you will need the new XDCA FX9 extension unit for raw). I don’t need to buy new base plates as existing FS7 plates will fit, as will most top plates. There is a small change on the top of the camera as every opening now has water and dust sealing gaskets around it – the FX9 is very well sealed against bad weather and dust. So some FS7 top plates may not fit around the hole where the handle plugs in.

It takes the same BP-U batteries, so I don’t need to buy different batteries. But it does use more power, around twice as much as the FS7. The penalty you have to pay for a bigger sensor with more pixels and more processing power for LUT’s in more modes.

The viewfinder is much improved. It still has the same square rods as the FS7 MkII, which won’t be to everyone’s taste. But the display is now sharper and that makes focussing much easier. The new screen is 720P (the FS7 is 540P I think). So it’s already clearer and sharper. But on top of that the peaking has been improved and better still the focus mag is now very good. Zoom in and it doesn’t go all blocky and muddy, it remains clear and sharp. 

DSC_0410-2-1024x576 My take on the PXW-FX9
The much improved PXW-FX9 viewfinder.


There isn’t much not to like about the FX9 when you consider the price. If my clients could afford it I would love to have a Venice. But the reality is few of them can afford Venice. Besides, Venice is big and heavy. For my travels and adventures I think the FX9 is going to be a perfect fit and I can’t wait to shoot some more with one.

Sony’s Internal Recording Levels Are Correct.

There is a video on YouTube right now where the author claims that the Sony Alpha cameras don’t record correctly internally when shooting S-Log2 or S-Log3. The information contained in this video is highly miss-leading and the conclusion that the problem is with the way Sony record internally is incorrect. There really isn’t anything wrong with the way Sony do their recordings. Neither is there anything wrong with the HDMI output. While centered around the Alpha cameras the information below is also important for anyone that records S-Log2 or S-log3 externally with any other camera.

Some background: Within the video world there are 2 primary ranges that can be used to record a video signal.

Legal Range uses code value 16 for black and code value 235 for white (anything above CV235 is classed as a super-white and these can still be recorded but considered to be beyond 100%).

Full or Data Range uses code value 0 for black and code value 255 for white or 100%.

Most cameras and most video systems are based on legal range. ProRes recordings are almost always legal range. Most Sony cameras use legal range and do include super-whites for some of the curves such as Cinegammas or Hypergammas to gain a bit more dynamic range. The vast majority of video recordings use legal range. So most software defaults to legal range.

But very, very importantly – S-log2 and S-log is always full/data range.

Most of the time this doesn’t cause any issues. When you record internally in the camera the internal recordings have metadata that tells the playback, editing or grading software that the S-Log files have been recorded using full range. Because of this metadata the software will play the files back and process them at the correct levels. However if you record the S-Log with an external recorder the recorder doesn’t always know that what it is getting is full range and not legal range, it just records it, as it is, exactly as it comes out of the camera. That then causes a problem later on because the externally recorded file doesn’t have the right metadata to ensure that the full range S-Log material is handled correctly and most software will default to legal range if it knows no different.

Lets have a look at what happens when you import an internally recorded S-Log2 .mp4 file from a Sony A7S into Adobe Premiere:

Screenshot-2019-03-01-at-10.04.22 Sony's Internal Recording Levels Are Correct.
Internal S-Log2 in Premiere.

A few things to note here. One is Adobe’s somewhat funky scopes where the 8 bit code values don’t line up with the normally used IRE values used for video productions. Normally 8 bit code value 235 would be 100IRE or 100%, but for some reason Adobe have code value 255 lined up with 100%. My suspicion is that the scope % scale is not video % or IRE but instead RGB%. This is really confusing. A further complication is that Adobe have code value 0 as black, again, I think, but am not sure that this is RGB code value 0. In the world of video Black should be code value 16. But the scopes appear to work such that 0 is black and that 100 is full scale video out. Anything above 100 and below 0 will be clipped in any file you render out.

Looking at the scopes in the screen grab above, the top step on the grey scale chart is around code value 252. That is the code value you would expect it to be, that lines up just nicely with where the peak of an S-Log2 recording should be. This all looks correct, nothing goes above 100 or below 0 so nothing will be clipped.

So now lets look at an external ProRes recording, recorded at exactly the same time as the internal recording and see what Premier does with that:

Screenshot-2019-03-01-at-10.05.32 Sony's Internal Recording Levels Are Correct.
External ProRes in Adobe Premiere

OK, so we can see straight away something isn’t quite right here. In an 8 bit recording it should be impossible to have a code value higher that 255, but the scopes are suggesting that the recording has a peak code value of something around CV275. That is impossible, so alarm bells should be ringing. Something is not quite right here. In addition the S-Log2 appears to be going above 100, so that means if I were to simply export this as a new file, the top of the recording will be clipped and it won’t match the original. This is very clearly not right.

Now lets take a look at what happens in Adobe Premiere when you apply Sony’s standard S-Log2 to Rec-709 LUT to a correctly exposed internal recording:

Screenshot-2019-03-01-at-10.10.05 Sony's Internal Recording Levels Are Correct.
Internal S-Log2 with 709 LUT applied.

This all looks good and as expected. Blacks are sitting down just above the 0 line (which I think we can safely assume is black) and the whites of the picture are around code value 230 or 90, whatever that means. But they are certainly nice and bright and are not in the range that will be clipped. So I can believe this as being more or less correct and as expected.

So next I’m going to add the same standard LUT to the external recording to see what happens.

Screenshot-2019-03-01-at-10.11.24 Sony's Internal Recording Levels Are Correct.
External S-Log2 with standard 709 LUT applied.

OK, this is clearly not right. Our blacks now go below the 0 line and they look clipped. The highlights don’t look totally out of place, but clearly there is something going very, very wrong when we this normal LUT to this correctly exposed external recording. There is no way our blacks should be going below zero and they look crushed/clipped. The internal recording didn’t behave like this. So what is going on with the external recording?

To try and figure this out lets take a look at the same files in DaVinci Resolve. For a start I trust the scopes in Resolve much more and it is a far better programme for managing different types of files. First we will look at the internal S-Log2 recording:

Screenshot-2019-03-01-at-10.21.17-1 Sony's Internal Recording Levels Are Correct.
Internal S-Log2, all looks good.

Once again the levels of the internal S-Log2 recordings look absolutely fine. Our peak is around code value 1010 which would be 252 in 8 bit. Right where the brightest bits of an S-log2 file should be. Now lets take a look at the external recording.

Screenshot-2019-03-01-at-10.22.51 Sony's Internal Recording Levels Are Correct.
External ProRes S-Log2 (Full Range)

If you compare the two screen grabs above you can see that the levels are exactly the same. Our peak level is around CV1010/CV252, just where it should be and the blacks look the same also. The internal and external recordings have the same levels and look the same. There is no difference (other then perhaps less compression and fewer artefacts in the ProRes file). There is nothing wrong with either of these recordings and certainly nothing wrong with the way Sony record S-Log2 internally. This is absolutely what I expect to see.

BUT – I’ve been a little bit sneaky here. As I knew that the external recording was a full range recording I told DaVinci Resolve to treat it as a full range recording. In the media bin I right clicked on the clip and under “clip attributes” I changed the input range from “auto” to “full”. If you don’t do this DaVinci Resolve will assume the ProRes file to be legal range and it will scale the clip incorrectly in the same way as Premiere does. But if you tell Resolve the clip is full range then it is handled correctly.

This is what it looks like if you allow Resolve to guess at what range the S-Log2 full range clip is by leaving the input range setting to “auto”:

Screenshot-2019-03-01-at-10.24.46 Sony's Internal Recording Levels Are Correct.
External ProRes S-Log2 Auto Range

In the above image we can see how in Resolve the clip becomes clipped because in a legal range recording anything over CV235/CV940 would be an illegal super white. Resolve is scaling the clip and pushing anything in the original file that was above CV235/CV940 off the top of the scale. The scaling is incorrect because Resolve doesn’t know the clip is supposed to be full range and therefore not scaled. If we compare this to what Premiere did with the external recording it’s actually very similar. Premiere also scaled the clip, only Premiere will show all those “illegal” levels above it’s 100 line instead of clipping then as Resolve does. That’s why Premiere can have those “impossible” 8 bit code values going up to CV275.

Just to be complete here, I did also test the internal .mp4 recordings in Resolve switching between “auto” and “full” range and in both cases the levels stayed exactly the same. This shows that Resolve is correctly handling the internally record full range S-Log as full range.

What about if you add a LUT? Well you MUST tell Resolve to treat the S-Log2 ProRes clip as a full range clip otherwise the LUT will not be right, if your footage is S-Log3 you also have to tell Resolve that it is full range:

Screenshot-2019-03-01-at-13.09.16 Sony's Internal Recording Levels Are Correct.
Resolve: Internal recording with the standard 709 LUT applied, all is exactly as expected. Deep shadows and white right at the top of the range.
Screenshot-2019-03-01-at-13.10.10 Sony's Internal Recording Levels Are Correct.
Resolve: External recording with the standard 709 LUT applied, clip input range set to “full”. Everything is once again as you would expect. Deep shadows and white at the top of the range. Also not that it is near perfect match to the internal recording. No hue or color shift (Premiere introduces a color shift, more on that later).
Screenshot-2019-03-01-at-13.14.02 Sony's Internal Recording Levels Are Correct.
Resolve: External recording with the standard 709 LUT applied, clip input range set to “auto”. This is clearly not right. The highlights are clipped and the blacks are crushed and clipped. It is so important to get the input range right when working with LUT’s!!

CONCLUSIONS:

Both the internal and external recordings are actually exactly the same. Both have the same levels, both use FULL range. There is absolutely nothing wrong with Sony’s internal recordings. The problem stems from the way most software will assume that the ProRes files are legal range. But if it’s an S-Log2 or S-Log3 recording it will in fact be full (data) range. Handling a full range clip as legal range means that highlights will be too high/bright or clipped and blacks will be crushed. So it’s really important that your software handles the footage correctly. If you are shooting using S-Log3 this problem is harder to spot as S-Log3 has a peak recording level that is well with the legal range, so you often won’t realise it’s being scaled incorrectly as it won’t necessarily look clip. If you use LUT’s and your ProRes clips look crushed or highlights look clipped you need to check that the input scaling is correct. It’s really important to get this right.

Why is there no difference between the levels when you shoot with a Cinegamma? Well when you shoot with a cinegamma the internal recordings are legal range so the internal recordings get treated as legal range and so do the external recordings, so they don’t appear to be different (In the YouTube video that led to this post the author discovers that if you record with a normal profile first and then switch to a log profile while recording the internal and external files will match. But this is because now the internal recording has the incorrect metadata, so it too gets scaled incorrectly, so both the internal and external files are now wrong – but the the same).

Once again: There is nothing wrong with the internal recordings. The problem is with the way the external recordings are being handled. The external recordings haven’t been recorded incorrectly, they have been recorded as they should be. The problem is the edit software is incorrectly interpreting the external recordings. The external recordings don’t have the necessary metadata to mark the files as full range because the recorder is external to the camera and doesn’t know what it’s being sent by the camera. This is a common problem when using external recorders.

What can we do in Premiere to make Premiere work right with these files?

You don’t need to do anything in Premiere for the internal .mp4 recordings. They are handled correctly but Premiere isn’t handling the full/data range ProRes files correctly.

My approach for this has always been to use the legacy fast color corrector filter to transform the input range to the required output range. If you apply the fast color corrector filter to a clip you can use the input and output level sliders to set the input and output range. In this case we need to set the output black level to CV16 (as that is legal range black) and we need to set output white to CV235 to match legal range white. If you do this you will then see that the external recording appears to have almost exactly the same values as the internal recording. However there is some non-linearity in the transform, it’s not quite perfect. So if anyone knows of a better way to do this do please let me know.

Screenshot-2019-03-01-at-11.04.04 Sony's Internal Recording Levels Are Correct.
Using the legacy “fast color corrector” filter to transform the external recording to the correct range within Premiere.

Now when you apply a LUT the picture and the levels are more or less what you would expect and almost identical to the internal recordings. I say almost because there is a slight hue shift. I don’t know where the hue shift comes from. In Resolve the internal and external recordings look pretty much identical and there is no hue shift. In Premiere they are not quite the same. The hue is slightly different and I don’t know why. My recommendation – use Resolve, it’s so much better for anything that needs any form of grading or color correction.

Atomos Ninja V, the arctic and the Northern Lights.

I’m sitting here in the UK, Its February and it almost 20c (68f). Very nice indeed for the UK this time of year. Just a couple of weeks ago I was in Northern Norway, up above the arctic circle running one of my annual Northern Lights adventure tours. The weather there was very different. At no time did the temperature get above -15c(5f) and for most of the trip it was around -24c(-11f) both during the day and during the night.

Now, you might consider me a sadist when I say this, but for my Northern Lights trips I normally want it to be -20c or colder. The reason being that when it’s very cold like this we normally get beautifully clear skies. And we need clear skies to see the Aurora.

DSC_0249 Atomos Ninja V, the arctic and the Northern Lights.
Everyone all wrapped up for the hour long ride by snow scooter and sledge to the cabins that we stay at.

After many years of taking a full size video camera up to Norway I decided to go light this year and just take my trusty A7S and A6300 cameras. We get around on snow scooters and on sledges towed behind the snow scooters. This can make lugging around a larger camera tricky and there are times when you just can’t take a big camera. But in order to get the very best from these cameras I also decided to take an Atomos Ninja V.

DSC_0253 Atomos Ninja V, the arctic and the Northern Lights.
Out and about on the snow scooter. It really is a very beautiful place in the winter.

The Ninja V is the first of a new generation of recorders and monitors from Atomos. It’s much smaller than the Shogun range of recorders making it a better size and weight match for smaller cameras and DSLR’s. It has a very, very nice 5″ screen with a maximum brightness of 1000 Nits. The 1000 Nit output and Atomos’s clever way of driving it means it can display both SDR and HDR images depending on how it is set up. A key difference between the Shogun and the Ninja devices is that the Shoguns have both SDI inputs and HDMI inputs while the Ninja only has an HDMI input. But if your using this with a DSLR than only has an HDMI output, as I was, the lack of SDI connectors is not a problem.

DSC_0281 Atomos Ninja V, the arctic and the Northern Lights.
Shooting a sunset with the Ninja V on my A6300. We were way up on the Finnmarksvidda when this image was taken, absolutely in the middle of nowhere and it was -27c!

The build quality of the Ninja V is really good. Most of the body is made of aluminium. The rear part where the slots for the SSD and battery are is made from plastic, but it appears to be a good high quality and tough plastic. A new feature is an “AtomX” expansion port tucked inside the battery compartment. The expansion port allow different modules to be attached to the Ninja V to add functionality such a video over IP (ethernet) using the Newtek NDI protocol for live streaming or to turn the Ninja V into an IP connected monitor. There is also an AtomX sync module that allows you to wirelessly synchronise timecode and control multiple Ninja V”s on a single network and to use Bluetooth remote control. You can find out more about the AtomX modules here https://www.atomos.com/AtomX

Anyway – back to Norway. We were very lucky with the weather, and with the Northern Lights. On the first night at the cabins we stay at the Aurora put on a pretty good display. I was shooting with my Sony A7S with a Sigma Art 20mm f1.4 lens. I was shooting a mix of time-lapse, in which case I simply record the raw frames in the camera on it’s internal SD cards as well as real time video.

DSC09536-small Atomos Ninja V, the arctic and the Northern Lights.
The Aurora put on a great display for us on several nights.

The Northern Lights are only rarely very bright. Most of the time they are fairly dim. So I was using the Sigma lens wide open, shooting at 24fps and with the shutter at 1/24th. The adjusting the cameras ISO to get a nice bright image. At times this did mean I was using some very high ISO’s with a lot of gain. Shooting like this is going to put a lot of strain on any codec. But the Long GOP XAVC-S codec used in the A7S is going to be very hard pushed to not introduce a lot of additional artefacts. In addition my older original A7S can only record HD internally.

By using the Ninja V I was able to record video of the Northern Lights in 4K using the ProRes codec. I used ProRes HQ and ProResHQ uses much less compression than XAVC-S. So even though both the internal recordings and the external recordings are limited to 8 bit (due to the cameras HDMI output limitations rather than any limitation of the Ninja) the ProRes recordings are far more robust and will noise reduce in post much better than the XAVC-S.

DSC_0278-crop Atomos Ninja V, the arctic and the Northern Lights.
Just to prove it really was -27c!!

When you’re working outside for extended periods and it’s -27c(-17f) it’s tough on the gear and tough on you. When shooting the Aurora my camera are outside all night, exposed to the cold. Typical problems include frost and ice on the front element of the lens. The moisture from your own body can easily freeze onto the lens if you stand close to the camera. If you look at the lens to check it for frost and breath out you will leave it coated in ice.

Wires and cables that are soft and flexible in normal temperatures become as stiff as steel rods and can crack and fracture if you try to bend them. All batteries will loose some of their capacity. Very small batteries are worst affected. Larger batteries tend to fair a bit better, but there is a tremendous difference between the way most cheap budget batteries behave in the cold to good quality brand name batteries. For this reason I power my complete setup from a single PAG PAGLink V-Mount battery. The PAGlink batteries are great for all sorts of different applications, but for these trips a big benefit is that a small plug type charger can be used to charge many PAGlink batteries by stacking the batteries together. Then to power multiple devices I use the clip-on PAG Power hub plate to provide 5V for the camera battery adapters that I use, 12V for the lens heaters I use and another 12V feed for the Ninja V.

DSC_0311 Atomos Ninja V, the arctic and the Northern Lights.
This is what the kit looks like when you bring it into the warm after many hours out in the cold. The thing with the yellow strap on the lens is a lens heater to prevent frost from building up on the lens. The lens is a sigma 20mm f1.4, the camera is an A7S and the recorder is the Atomos Ninja V.

After more than a few minutes outside the camera kit itself will have become extremely cold. If you then take that kit inside into a nice warm cabin the warm moist air in the cabin will condense onto the cold camera body. Because the camera body will be extremely cold this will then freeze. Before you know it the camera kit is covered in ice. What you can’t see is that it’s likely that there will also be some ice and moisture inside the camera. It can take hours to warm the camera back up again and get it dried out properly. Bagging the camera before you take it indoors can help, but taking the camera in and out many times over the coarse of a shoot like this can cause a lot of damage. So I prefer to leave all the camera kit outside for the duration of the trip.

DSC_0314 Atomos Ninja V, the arctic and the Northern Lights.
Another view of the frozen Ninja V after a night shooting the Aurora. Don’t worry, the screen isn’t damaged, that’s just frost and ice on the screens surface.

This means that when you come to fire it up you are often trying to switch on an absolutely frozen camera. In the past I have had problems with cold recorders that wouldn’t start up. But I’m pleased to report that the Ninja V always came to life no matter how cold it was. Whenever I pressed the record button it went into record. Operating the touch screen in the cold was not an issue. In fact using touch screen gloves, the Ninja was really easy to use. Pressing small fiddly buttons isn’t easy, even with thin gloves, but the touch screen turned out really easy to work with.

A big change on the Ninja V over previous models is the operating system. The new operating system looks really good and is quite logically laid out. Gone is the old AtomHDR slider that changes the brightness of the screen when in HDR. This is replaced with dedicated viewing modes for Native, 709, PQ HDR and HLG HDR and viewing via a LUT. I prefer the new fixed HDR modes over the Atom HDR slider modes as it eliminates the uncertainty that can sometimes creep in when you use a slider to change the brightness of the display. In my case, when shooting during the day using S-Log2 I would simply select S-Log2 as the source and then use PQ to display an HDR image on the screen. At night when shooting the Aurora I used Rec-709.

DSC_0283 Atomos Ninja V, the arctic and the Northern Lights.
You can see how the normal size 2.5″ SSD sticks out a bit from the side of the Ninja V. The SSDMini’s don’t stick out in the same way. Also note that even though I am shooting using S-Log2 on the A6300 the Ninja V is showing a nice contrasty image thanks to the PQ HDR display option.

The Ninja V can take the same size 2.5″ SSD caddies as the current Shogun recorders. So I was able to use the SSD’s that I already own. However to keep the size of the recorder down it has been designed around a new slightly shorty SSD form factor called SSDMini. When you use a standard size 2.5″ SSD it does stick out from the side of the recorder by about 25mm. If you use an SSDMini it doesn’t stick out at all. SSDMini’s are currently being manufactured by Angelbird and Sony. They have the same sata connector as regular 2.5″ SSD’s and the SSDMini’s can also be used on the larger Atomos Shoguns.

DSC_0286 Atomos Ninja V, the arctic and the Northern Lights.
A basic lightweight but effective setup. Atomos Ninja V, Sony A6300, Miller Compass 15 head and Solo tripod.

By the time we were ready to leave Norway we had seen the Northern Lights on 3 different nights. By day we had seen some beautiful sunrises as well as other optical effects like sun dogs caused by the light from the sun being refracted by ice crystals in the air. The Atomos Ninja V had impressed me hugely. It just worked perfectly despite the extreme cold. It allowed me to record at higher quality than would have been possible without it and turned out to be easy to operate. What more can you want really?

Fancy joining me on one of these trips? Follow the link to find out more: http://www.xdcam-user.com/northern-lights-expeditions-to-norway/