Tag Archives: FX9

Shooting S-Log3 on the PXW-FX9 – Do I need to expose bright?

Having shot quite a bit of S-Log3 content on the new Sony PXW-FX9 I thought I would comment on my exposure preferences. When shooting with an FS5, FS7 or F5, which all use the same earlier generation 4K sensor I find that to get the best results I need to expose between 1 and 2 stops brighter than the 41% for middle grey that Sony recommend. This is because I find my footage to be noisier than I would like if I don’t expose brighter. So when using CineEI on these cameras I use 800EI instead of the base 2000EI

However the FX9 uses a newer state of the art back illuminated sensor. This more sensitive sensor produces less noise so with the FX9 I no longer feel it is necessary to expose more brightly than the base exposure – at either of the base ISO’s. So if I am shooting using CineEI and 800 base, I use 800EI. When shooting at 4000 base, I use 4000 EI. 

This makes life so much easier. It also means that if you are shooting in a mode where LUT’s are not available (such as 120fps HD) then you can use the included viewfinder gamma assist function instead. Viewfinder gamma assist adds the same 709(800) look to the viewfinder as you would get from using the cameras built in 709(800) LUT.  You can use the VF gamma assist to help judge your exposure just as you would with a LUT.  Basically, if it looks right in the viewfinder, it almost certainly is right.

Testing various FX9’s against my Sekonic light meter the cameras CineEI ISO ratings seem to be spot on. So I would have no concerns if using a light meter to expose.  The camera also has a waveform scope and zebras to help guide your exposure.

VF Gamma assist is available in all modes on the FX9, including playback. Just be careful that you don’t have both a LUT on and gamma assist at the same time.

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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 or look was then 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 migh 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, with a touch of extra contrast.

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 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).

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 and 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. Plus S-Cinetone 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.

The FX9 has (amongst others) a colour science that makes it look very similar to the default Venice look. In custom this is called S-Cinetone. Select a different gamma or different matrix and the pictures will look different, so this will be a different colour science, even though the same sensor is being used.

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.

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.