Category Archives: cinematography

Using LUT’s for exposure – choosing the right LUT.

If using a LUT to judge the exposure of a camera shooting log or raw it’s really important that you fully understand how that LUT works.

When a LUT is created it will expect a specific input range and convert that input range to a very specific output range. If you change the input range then the output will range will be different and it may not be correct. As an example a LUT designed and created for use with S-Log2 should not be used with S-Log3 material as the the higher middle grey level used by S-Log3 would mean that the mid range of the LUT’s output would be much brighter than it should be.

Another consideration comes when you start offsetting your exposure levels, perhaps to achieve a brighter log exposure so that after grading the footage will have less noise.

Lets look at a version of Sony’s 709(800) LUT designed to be used with S-Log3 for a moment. This LUT expects middle grey to come in at 41% and it will output middle grey at 43%. It will expect a white card to be at 61% and it will output that same shade of white at a little over 85%. Anything on the S-Log3 side brighter than 61% (white) is considered a highlight and the LUT will compress the highlight range (almost 4 stops) into the output range between 85% and 109% resulting in flat looking highlights. This is all perfectly fine if you expose at the levels suggested by Sony. But what happens if you do expose brighter and try to use the same LUT either in camera or in post production?

Well if you expose 1.5 stops brighter on the log side middle grey becomes around 54% and white becomes around 74%. Skin tones which sit half way between middle grey and white will be around 64% on the LUT’s input. That’s going to cause a problem! The LUT considers anything brighter than 61% on it’s input to be a highlight and it will compresses anything brighter than 61%. As a result on the output of your LUT your skin tones will not only be bright, but they will be compressed and flat looking. This makes them hard to grade. This is why if you are shooting a bit brighter it is much, much easier to grade your footage if your LUT’s have offsets to allow for this over exposure.

If the camera has an EI mode (like the FS7, F5, F55 etc) the EI mode offsets the LUT’s input so you don’t see this problem in camera but there are other problems you can encounter if you are not careful like unintentional over exposure when using the Sony LC709 series of LUTs.

Sony’s  709(800) LUT closely matches the gamma of most normal monitors and viewfinders, so 709(800) will deliver the correct contrast ie. contrast that matches the scene you are shooting plus it will give conventional TV brightness levels when viewed on standard monitors or viewfinders.

If you use any of the LC709 LUT’s you will have a miss-match between the LUT’s gamma and the monitors gamma so the images will show lower contrast and the levels will be lower than conventional TV levels when exposed correctly. LC709 stands for low contrast gamma with 709 color primaries, it is not 709 gamma!

Sony’s LC709 Type A LUT is very popular as it mimics the way an Arri Alexa might look. That’s fine but you also need to be aware that the correct exposure levels for this non-standard LC gamma are middle grey at around 41% and white at 70%.

An easy trap to fall into is to set the camera to a low EI to gain a brighter log exposure and then to use one of the LC709 LUT’s and try to eyeball the exposure. Because the LC709 LUT’s are darker and flatter it’s harder to eyeball the exposure and often people will expose them as you would regular 709. This then results in a double over exposure. Bright because of the intentional use of the lower EI but even brighter because the LUT has been exposed at or close to conventional 709 brightness. If you were to mistakenly expose the LC709TypeA LUT with skin tones at 70%, white at 90% etc then that will add almost 2 stops to the log exposure on top of any EI offset.

Above middle grey with 709(800) a 1 stop exposure change results in an a 20% change in brightness, with LC709TypeA the same exposure change only gives a just over 10% change, as a result over or under exposure is much less obvious and harder to measure or judge by eye with LC709. The cameras default zebra settings for example have a 10% window. So with LC709 you could easily be a whole stop out, while with 709(800) only half a stop.

Personally when shooting I don’t really care too much about how the image looks in terms of brightness and contrast. I’m more interested in using the built in LUT’s to ensure my exposure is where I want it to be. So for exposure assessment I prefer to use the LUT that is going to show the biggest change when my exposure is not where it should be. For the “look” I will feed a separate monitor and apply any stylised looks there. To understand how my highlights and shadows, above and below the LUT’s range are being captured I use the Hi/Low Key function.

If you are someone that creates your own LUT’s an important consideration is to ensure that if you are shooting test shots, then grading these test shots to produce a LUT it’s really, really important that the test shots are very accurately exposed.

You have 2 choices here. You can either expose at the levels recommended by Sony and then use EI to add any offsets or you can offset the exposure in camera and not use EI but instead rely on the offset that will end up in the LUT. What is never a good idea is to add an EI offset to a LUT that was also offset.

More on frame rate choices for todays video productions.

This is another of those frequent questions at workshops and online.
What frame rate is the best one to use?
First – there is no one “best” frame rate. It really depends on how you want your video to look. Do you want the slightly juddery motion of a feature film or do you want silky smooth motion?
You also need to think about and understand how your video will be viewed. Is it going to be watched on a modern TV set or will it be watched on a computer? Will it only be watched in one country or region or will it be viewed globally?
Here are some things to consider:
TV in Europe is normally 50Hz, either 25p or 50i.
TV in the North America is 60Hz, either 30p or 60i (both actually 29.97fps).
The majority of computer screens run at 60Hz.
Interlaced footage looks bad on most LCD screens.
Low frame rates like 24p and 25p often exhibit judder.
Most newer, mid price and above TV’s use motion estimation techniques to eliminate judder in low frame rate footage.
If you upload 23.98fps footage to YouTube and it is then viewed on a computer it will most likely be shown at 24p as you can’t show 0.98 of a frame on a 60Hz computer screen.
Lets look first at 25p, 50i and 50p.
If you live in Europe or another 50Hz/Pal area these are going to be frame rates you will be familiar with. But are they the only frame rates you should use? If you are doing a broadcast TV production then there is a high chance that you will need to use one of these standards (please consult whoever you are shooting for). But if your audience is going to watch your content online on a computer screen, tablet or mobile phone these are not good frame rates to use.

Most computer screens run at 60Hz and very often this rate can’t be changed. 25p shown on most computer screens requires 15 frames to be shown twice and 10 frames to be shown 3 times to create a total of 60 frames every second. This creates an uneven cadence and it’s not something you can control as the actual structure of the cadence depends on the video subsystem of the computer the end user is using.

The odd 25p cadence is most noticeable on smooth pans and tilts where the pan speed will appear to jump slightly as the cadence flips between the 10 frame x3 and 15 frame x 2 segments. This often makes what would otherwise be smooth motion appear to stutter unevenly. 24p material doesn’t exhibit this same uneven stutter (see the 24p section). 50p material will exhibit a similar stutter as again the number of padding frames needed is uneven, although the motion should be a bit more fluid.
So really 25p and 50p are best reserved for material that will only ever be seen on televisions that are running at 50Hz. They are not the best choices for online distribution or viewing on computers etc.
24p, 30p or 60p (23.98p, 29.97p)
If you are doing a broadcast TV show in an NTSC/60Hz area then you will most likely need to use the slightly odd frame rates of 23.98fps or 29.97fps. These are legacy frame rates specifically for broadcast TV. The odd frame rates came about to avoid problems with the color signal interfering with the luma (brightness) signal in the early days of analog color TV.
If you show 23.98fps or 29.97fps footage on a computer it will normally be shown at the equivalent of 24p or 30p  to fit with the 60Hz refresh rate of the computer screen. In most cases no one will ever notice any difference.
24p Cadence.
23.98p and 24p when shown on a 60Hz screen are shown by using 2:3 cadence where the first frame is shown twice, the next 3 times, then 2, then 3 and so on. This is very similar to the way any other movie or feature film is shown on TV and it doesn’t look too bad.
30p or 29.97p footage will look smoother than 24p as all you need to do is show each frame twice to get to 60Hz there is no odd cadence and the slightly higher frame rate will exhibit a little less judder. 60p will be very smooth and is a really good choice for sports or other fast action. But, higher frame rates do require higher data rates to maintain the same image quality. This means larger files and possibly slower downloads and must be considered. 30p is a reasonable middle ground choice for a lot of productions, not as juddery as 24p but not as smooth as 60p.
24p or 23.98p for “The Film Look”.
Generally if you want to mimic the look of a feature film then you might choose to use 23.98p or 24p as films are normally shot at 24fps. If your video is only going to be viewed online then 24p is a good choice. If your footage might get shown on TV the 23.98p may be the better choice as 23.98fps works well on 29.97fps TV’s in 60Hz/NTSC areas.
BUT THERE IS A NEW CATCH!!!
A lot of modern, new TV’s feature motion compensation processes designed to eliminate judder. You might see things in the TV’s literature such as “100 Hz smooth motion” or similar.  If this function is enabled in the TV it will take any low frame rate footage such as 24p or 25p and use software to create new frames to increase the frame rate and smooth out any motion judder.
So if you want the motion judder typical of a 24fps movie and you create at 24fps video, you may find that the viewer never sees this juddery, film like motion as the TV will do it’s best to smooth it out! Meanwhile someone watching the same clip on a computer will see the judder. So the motion in the same clip will look quite different depending on how it’s viewed.
Most TV’s that have this feature will disable it it when the footage is 60p as 60p footage should look smooth anyway. So a trick you might want to consider is to shoot at 24p or 30p and then for the export file create a 60p file as this will typically cause the TV to turn off the motion estimation.
In summary, if you are doing a broadcast TV project you should use the frame rate specified by the broadcaster. But for projects that will be distributed via the internet I recommend the use of 23.98p or 24p for film style projects and 30p for most other projects. However if you want very smooth motion you should consider using 60p.

Why hasn’t anyone brought out a super sensitive 4K camera?

Our current video cameras are operating at the limits of current sensor technology. As a result there isn’t much a camera manufacturer can do to improve sensitivity without compromising other aspects of the image quality.
Every sensor is made out of silicon and silicon is around 70% efficient at converting photons of light into electrons of electricity. So the only things you can do to alter the sensitivity is change the pixel size, reduce losses in the colour and low pass filters, use better micro lenses and use various methods to prevent the wires and other electronics on the face of the sensor from obstructing the light. But all of these will only ever make very small changes to the sensor performance as the key limiting factor is the silicon used to make the sensor.
 
This is why even though we have many different sensor manufacturers, if you take a similar sized sensor with a similar pixel count from different manufacturers the performance difference will only ever be small.
 
Better image processing with more advanced noise reduction can help reduce noise which can be used to mimic greater sensitivity. But NR rarely comes without introducing other artefacts such as smear, banding or a loss of subtle details. So there are limits as to how much noise reduction you want to apply. 
 

So, unless there is a new sensor technology breakthrough we are unlikely to see any new camera come out with a large, actual improvement in sensitivity. Also we are unlikely to see a sudden jump in resolution without a sensitivity or dynamic range penalty with a like for like sensor size. This is why Sony’s Venice and the Red cameras are moving to larger sensors as this is the only realistic way to increase resolution without compromising other aspects of the image. It’s why all the current crop of S35mm 4K cameras are all of very similar sensitivity, have similar dynamic range and similar noise levels.

 

A great example of this is the Sony A7s. It is more sensitive than most 4K S35 video cameras simply because it has a larger full frame sensor, so the pixels can be bigger, so each pixel can capture more light. It’s also why cameras with smaller 4K sensors will tend to be less sensitive and in addition have lower dynamic range (because the pixel size determines how many electrons it can store before it overloads).

Why do we strive to mimic film? What is the film look anyway?

 

Please don’t take this post the wrong way. I DO understand why some people like to try and emulate film. I understand that film has a “look”. I also understand that for many people that look is the holy grail of film production. I’m simply looking at why we do this and am throwing the big question out there which is “is it the right thing to do”? I welcome your comments on this subject as it’s an interesting one worthy of discussion.

In recent years with the explosion of large sensor cameras with great dynamic range it has become a very common practice to take the images these cameras capture and apply a grade or LUT that mimics the look of many of todays major movies. This is often simply referred to as the “film look”.

This look seems to be becoming more and more extreme as creators attempt to make their film more film like than the one before, leading to a situation where the look becomes very distinct as opposed to just a trait of the capture medium. A common technique is the “teal and orange” look where the overall image is tinted teal and then skin tones and other similar tones are made slightly orange. This is done to create colour contrast between the faces of the cast and the background as teal and orange are on opposite sites of the colour wheel.

Another variation of the “film look” is the flat look. I don’t really know where this look came from as it’s not really very film like at all. It probably comes from shooting with a log gamma curve, which results in a flat, washed out looking image when viewed on a conventional monitor. Then because this look is “cool” because shooting on log is “cool” much of the flatness is left in the image in the grade because it looks different to regular TV ( or it may simply be that it’s easier to create a flat look than a good looking high contrast look). Later in the article I have a nice comparison of these two types of “film look”.

Not Like TV!

Not looking like TV or Video may be one of the biggest drivers for the “film look”. We watch TV day in, day out. Well produced TV will have accurate colours, natural contrast (over a limited range at least) and if the TV is set up correctly should be pretty true to life. Of course there are exceptions to this like many daytime TV or game shows where the saturation and brightness is cranked up to make the programmes vibrant and vivid.  But the aim of most TV shows is to look true to life. Perhaps this is one of the drivers to make films look different, so that they are not true to life, more like a slightly abstract painting or other work of art. Colour and contrast can help setup different moods, dull and grey for sadness, bright and colourful for happy scenes etc, but this should be separate from the overall look applied to a film.

Another aspect of the TV look comes from the fact that most TV viewing takes place in a normal room where light levels are not controlled. As a result bright pictures are normally needed, especially for daytime TV shows.

But What Does Film Look Like?

But what does film look like? As some of you will know I travel a lot and spend a lot of time on airplanes. I like to watch a film or 2 on longer flights and recently I’ve been watching some older films that were shot on film and probably didn’t have any of the grading or other extensive manipulation processes that most modern movies go through.

Lets look at a few frames from some of those movies, shot on film and see what they look like.

Lawrence of Arabia.

The all time classic Lawrence of Arabia. This film is surprisingly colourful. Red, blues, yellows are all well saturated. The film is high contrast. That is, it has very dark blacks, not crushed, but deep and full of subtle textures. Skin tones  are around 55 IRE and perhaps very slightly skewed towards brown/red, but then the cast are all rather sun tanned. But I wouldn’t call the skin tones orange. Diffuse whites typically around 80 IRE and they are white, not tinted or coloured.

Braveheart.

When I watched Braveheart, one of the things that stood out to me was how green the foliage and grass was. The strong greens really stood out in this movie compared to more modern films. Overall it’s quite dark, skin tones are often around 45 IRE and rarely more than 55 IRE, very slightly warm/brown looking, but not orange. Again it’s well saturated and high contrast with deep blacks. Overall most scenes have a quite low peak and average brightness level. It’s quite hard to watch this film in a bright room on a conventional TV, but it looks fantastic in a darkened room.

Raiders Of The Lost Ark

Raiders of the Lost Ark does show some of the attributes often used for the modern film look. Skin tones are warm and have a slight orange tint and overall the movie is very warm looking. A lot of the sets use warm colours with browns and reds being prominent. Colours are well saturated. Again we have high contrast with deep blacks and those much lower than TV skin tones, typically 50-55IRE in Raiders. Look at the foliage and plants though, they are close to what you might call TV greens, ie realistic shades of green.

A key thing I noticed in all of these (and other) older movies is that overall the images are darker than we would use for daytime TV. Skin tones in movies seem to sit around 55IRE. Compare that to the typical use of 70% zebras for faces on TV. Also whites are generally lower, often diffuse white sitting at around 75-80%. One important consideration is that films are designed to be shown in dark cinema theatres where  white at 75% looks pretty bright. Compare that to watching TV in a bright living room where to make white look bright you need it as bright as you can get. Having diffuse whites that bit lower in the display range leaves a little more room to separate highlights from whites giving the impression of a greater dynamic range. It also brings the mid range down a bit so the shadows also look darker without having to crush them.

Side Note: When using Sony’s Hypergammas and Cingeammas they are supposed to be exposed so that white is around 70-75% with skin tones around 55-60%. If used like this with a sutable colour matrix such as “cinema” they can look quite film like.

If we look at some recent movies the look can be very different.

The Revenant

The Revenant is a gritty film and it has a gritty look. But compare it to Braveheart and it’s very different. We have the same much lower skin tone and diffuse white levels, but where has the green gone? and the sky is very pale.  The sky and trees are all tinted slightly towards teal and de-saturated. Overall there is only a very small colour range in the movie. Nothing like the 70mm film of Laurence of Arabia or the 35mm film of Braveheart.

Dead Men Tell No Tales.

In the latest instalment of the Pirates of the Caribbean franchise the images are very “brown”. Notice how even the whites of the ladies dresses or soldiers uniforms are slightly brown. The sky is slightly grey (I’m sure the sky was much bluer than this). The palm tree fronds look browner than green and Jack Sparrow looks like he’s been using too much fake tan as his face is border line orange (and almost always also quite dark).

Wonder Woman.

Wonder woman is another very brown movie. In this frame we can see that the sky is quite brown. Meanwhile the grass is pushed towards teal and de-saturated, it certainly isn’t the colour of real grass.  Overall colours are subdued with the exception of skin tones.

These are fairly typical of most modern movies. Colours generally quite subdued, especially greens and blues. The sky is rarely a vibrant blue, grass is rarely a grassy green. Skin tones tend to be very slightly orange and around 50-60IRE. Blacks are almost always deep and the images contrasty. Whites are rarely actually white, they tend to be tinted either slightly brown or slightly teal. Steel blues and warm browns are favoured hues. These are very different looking images to the movies shot on film that didn’t go through extensive post production manipulation.

So the film look, isn’t really about making it look like it was shot on film, it’s a stylised look that has become stronger and stronger in recent years with most movies having elements of this look. So in creating the “film look” we are not really mimicking film, but copying a now almost standard colour grading recipe that has some film style traits.

BUT IS IT A GOOD THING?

In most cases these are not unpleasant looks and for some productions the look can add to the film, although sometimes it can be taken to noticeable and objectionable extremes. However we do now have cameras that can capture huge colour ranges. We also have the display technologies to show these enormous colour ranges. Yet we often choose to deliberately limit what we use and very often distort the colours in our quest for the “film look”.

HDR TV’s with Rec2020 colour can show both a greater dynamic range and a greater colour range than we have ever seen before. Yet we are not making use of this range, in particular the colour range except in some special cases like some TV commercials as well as high end wild life films such as Planet Earth II.

This TV commercial for TUI has some wonderful vibrant colours that are not restricted to just browns and teal yet it looks very film like. It does have an overall warm tint, but the other colours are allowed to punch through. It feels like the big budget production that it clearly was without having to resort to  the modern defacto  restrictive film look colour palette. Why can’t feature films look like this? Why do they need to be dull with a limited colour range? Why do we strive to deliberately restrict our colour pallet in the name of fashion?

What’s even more interesting is what was done for the behind the scenes film for the TUI advert…..

The producers of the BTS film decided to go with an extremely flat, washed out look, another form of modern “film look” that really couldn’t be further from film. When an typical viewer watches this do they get it in the same way as we that work in the industry do?  Do they understand the significance of the washed out, flat, low contrast pictures or do they just see weird looking milky pictures that lack colour with odd skin tones? The BTS film just looks wrong to me. It looks like it was shot with log and not graded.  Personally, I don’t think it looks cool or stylish, it just looks wrong and cheap compared to the lush imagery in the actual advert (perhaps that was the intention).

I often see people looking for a film look LUT. Often they want to mimic a particular film. That’s fine, it’s up to them. But if everyone starts to home in on one particular look or style then the films we watch will all look the same. That’s not what I want. I want lush rich colours where appropriate. Then I might want to see a subdued look in a period piece or a vivid look for a 70’s film. Within the same movie colour can be used to differentiate between different parts of the story. Take Woody Allen’s Cafe Society, shot by Vittorio Storaro for example. The New York scenes are grey and moody while the scenes in LA that portray a fresh start are vibrant and vivid. This is I believe important, to use colour and contrast to help tell the story.

Our modern cameras give us an amazing palette to work with. We have the tools such as DaVinci Resolve to manipulate those colours with relative ease. I believe we should be more adventurous with our use of colour. Reducing exposure levels a little compared to the nominal TV and video – skin tones at 70% – diffuse whites at 85-90%, helps replicate the film look and also leaves a bit more space in the highlight range to separate highlights from whites which really helps give the impression of a more contrasty image. Blacks should be black, not washed out and they shouldn’t be crushed either.

Above all else learn to create different styles. Don’t be afraid of using colour to tell your story and remember that real film isn’t just brown and teal, it’s actually quite colourful. Great artists tend to stand out when their works are different, not when they are the same as everyone else.

 

What does ISO mean with todays cameras?

What is EXPOSURE?

Before diving into ISO, I think it’s first important to understand what exposure is. Exposure is the amount of light you put on to a sensor or film stock. Exposure is NOT brightness, brightness is – brightness. I can take an image in to post production and make it brighter or darker, but this doesn’t change how the image was exposed. Exposure is very specifically – how much light is allowed to hit the sensor or film stock and this is usually controlled by the shutter speed, aperture as well as perhaps ND filters.

What is ISO?

Once upon a time the meaning of ISO was quite clear. It was a standardised sensitivity rating for the film stock you were using. If you wanted more sensitivity, you used film with a higher ISO rating. But today the meaning of ISO is less clear. And lets not forget, we can’t swap our sensors out for more or less sensitive ones. So what does ISO mean given that we can’t actually change the sensor?

ISO is short for International Standards Organisation. And they specify many, many different standards for many different things. For example ISO 3166 is for telephone country codes, ISO 50001 is for energy management.

But in our world of film and TV there are two main ISO standards that we have blended into one and we just call it “ISO”.

ISO 5800:2001 is the system used to determine the sensitivity of color negative film found by plotting the density of the film against exposure to light.

ISO 12232:2006 specifies the method for assigning and reporting ISO speed ratings, ISO speed latitude ratings, standard output sensitivity values, and recommended exposure index values, for electronic cameras.

Note a key difference:

ISO 5800 is the measurement of the actual sensitivity to light of film.

ISO 12232 is a standardised way to report the speed rating, ie: it is not actually a direct sensitivity measurement.

So, from the above we can deduce that with film ISO is an actual sensitivity measurement. With an electronic camera it is a speed rating, not a measurement of the sensitivity, a rating.

Different Approaches and REI.

Within the digital camera ISO rating system there are 5 different standards that a camera manufacturer can use when obtaining the ISO rating of a camera. The most commonly used method is the Recommended Exposure Index (REI) method, which allows the manufacturer to specify a camera model’s base ISO arbitrarily, based on what the manufacturer believes produces a satisfactory image. So it’s not actually a measure of the cameras sensitivity, but a rating that if entered into a standard external light meter and the shutter and aperture values from the light meter used to set the exposure will result in satisfactory looking image.
This is very different to a sensitivity measurement and variations in opinion as to what is “a satisfactory image” will vary from person to person, manufacturer to manufacturer. For example – how much noise is considered acceptable? I know a lot of people with very different opinions on this! So, there is a lot of scope for movement as to how an electronic camera might be rated and we see this in the real world where two cameras both rated at the same ISO may have very different noise levels when exposed “correctly”.

You Can’t Change the Silicon!

As you cannot change the sensor in a digital camera, you cannot change the cameras efficiency at converting light into electrons which is largely determined by the materials used and the physical construction of the sensor. So, you cannot change the actual sensitivity of the camera to light. But we have all seen how the ISO number of most digital cameras can normally be increased (and sometimes lowered) from the base ISO number.

Higher and Lower ISO values.

Raising and lowering the ISO rating in an electronic camera is normally done by adjusting the amplification of the signal coming from the sensor, typically referred to as “gain” in the camera. It’s not actually a physical change in the cameras sensitivity to light. It is more like turning up the volume on an analog radio to make the music louder. Dual ISO cameras that claim not to add gain when switching between ISO’s typically do this by an adjustment at the sensors pixel level and this is closer to an actual sensitivity change. But generally this only gives two levels, not the multitude of ISO values offed by most cameras. While it is true that Dual ISO is different to a gain shift, it does typically alter the noise levels with the higher base ISO being slightly more noisy than the lower. With a true dual ISO sensor does do is produce the same dynamic range at both ISO’s.

Noise and Signal To Noise Ratio.

Most of the noise in the pictures we shoot comes from the sensor and sensor readout circuits and this noise level coming from the sensor is largely unchanged no matter what you do.

So, the biggest influence on the signal to noise ratio or SNR is the amount of light you put on the sensor because more light = more signal. The noise remains but with more light the signal is bigger so you get a better signal to noise ratio, up to the point where the sensor clips at which point adding more light makes no further difference.

But what about low light?

To obtain a brighter image when there the light levels are low and the picture coming from the sensor looks dark the signal coming from the sensor can be boosted or amplified (gain is added) by increasing the cameras ISO value. This extra signal amplification makes both the desirable signal bigger but at the same time as the noise cannot be separated form the image the noise also gets bigger by the same amount. If we make the desirable picture 2 times brighter we also make the noise 2 x bigger/brighter. As a result the picture will be brighter but the noise will appear greater than an exposure where we had enough light to get the brightness we want and didn’t need to add gain or raise the ISO.

More gain = less dynamic range.

The signal to noise ratio deteriorates because the added amplification means the recording will clip more readily. Something that was right at the recordings clip point without adding gain may will end up above the clip point by adding gain. As a result the highlight range you can record reduces while at the same time the noise gets bigger. But the optimum exposure is now achieved with less light so the equivalent ISO number is increased. If you were using a light meter you would increase the ISO setting on the light meter to get the correct exposure.

But the camera isn’t getting more sensitive, it’s just that the optimum amount of light for the “best” or “correct” exposure is reduced due to the added amplification.

So, with an electronic camera, ISO is a rating that will give you the correct recording brightness for the amount of light and the amount of gain that you have. This is different to sensitivity. Obviously the two are related, but they are not quite the same thing.

ISO in an electronic camera is not a sensitivity value, it is an exposure rating.

Getting rid of noise:

To combat the inevitable increase in the visibility of noise and the degraded signal to noise ratio that comes from adding gain/amplification, most modern cameras use electronic noise reduction which is applied more and more aggressively as you increase the gain. At low levels this goes largely un-noticed. But as you start to add more gain there will often be more noise reduction and this will start to degrade the image. It may become softer, it may become smeary. You may start to see banding, ghosting or other artefacts. Higher noise levels are also problematic for modern high compression codecs, so even if the camera doesn’t add extra noise reduction at high gain levels it is likely that the codec will do more noise reduction in an attempt to keep the recording bit rate under control.

Often as you increase the gain you may only see a very small increase in noise as the noise reduction does a very good job of hiding the noise. But for every bit of noise thats reduced there will be another artefact replacing it.

Technically the signal to noise ratio can be improved by the use of noise reduction, but this typically comes at a price and NR can be very problematic if you later want to grade or adjust the footage as often you won’t see the artefacts until after the corrections or adjustments have been made. So be very careful when adding gain. It’s never good to have extra gain.

So what does all of this mean?

The majority of the video cameras we use today are something known as ISO invariant. This mean that the actual sensitivity of the camera doesn’t actually change, even though the camera may offer you a wide range of ISO values. Instead we are adding gain to get a brighter picture, but extra gain degrades the signal to noise ratio and limits the dynamic range.

As well as adding gain in camera we can also add gain in post production. And if the quality of the recording codec is high enough there is almost no difference between adding the gain in post production compared to adding the gain in camera. If you don’t add gain in the camera then you don’t reduce the cameras dynamic range. By moving the gain addition to post production you can retain the cameras full dynamic range and overall the end result won’t be significantly different. This is why most Log cameras use some sort of Exposure Index system that locks the camera to it’s base sensitivity as this is where the camera will exhibit the greatest useable dynamic range.

What about using Picture Profiles of different Gamma Curves?

Different gamma curves have different gain levels. So, very often you will see a camera at it’s base sensitivity (ie: no added gain) give you different ISO values depending on the gamma curve you have chosen. Again – this doesn’t meant the sensitivity of the camera is different for each gamma curve. What it actually means is that the optimum exposure (exposure = amount of light you put on the sensor) is a bit different for each gamma curve.  For example when shooting S-Log3 the sensor is exposed lower than it is with normal gammas. This darker S-Log3 exposure leaves more room for an extended highlight range. The flip side to this is that when the camera is set at the correct, no extra gain added base ISO’s “correctly” exposed S-Log3 will be noisier than correctly exposed Rec-709 or S-Cinetone, but the S-Log3 will have a greater highlight range. If you were to expose the S-Log3 and the S-Cinetone using the same aperture and shutter speed the noise would be the same.

Picture Profiles for Low Light.

A question that gets asked a lot is: What’s the best picture profile or gamma for low light?

Well,  if you have followed all of the above then you will hopefully understand that the gamma or picture profile makes no difference to the actual sensitivity of the camera.  So in reality there is very little difference between any profile or gamma curve in terms of how the camera will perform in low light. Remember: it’s always the same sensor with the same noise and same sensitivity to light no matter what other settings you have chosen.

There might be some differences in the amount of noise reduction applied in different profiles and that might make a small difference. Many of Sony cameras allow you to adjust this between off/low/mid/high. But even if you can’t change this in camera, adding a bit of extra NR in post is a common practice these days.  Really, it’s a case of choosing the profile or gamma that gives you the image you want, S-Log3 if you intend to grade, perhaps S-Cinetone if you don’t. If you bring the S-Cinetone ISO value up to match the S-Log3 ISO value, the noise in the final image from both will be more or less the same.

Using what data you have.

Perhaps the only small consideration is that under exposed S-Log3 only uses a very small part of the cameras full recording range. You won’t be making use of the full recording data range. Because of this it might be hard to grade it without the image starting to look coarse or grainy.  Because of the smaller dynamic range, similarly exposed (same aperture, same shutter speed) S-Cinetone or Rec-709 will use more of the data range and might not look quite as coarse as a result. This difference is very small, but it should be considered if you are trying to squeeze something out of an extremely under exposed situation.

Sony Venice at IBC 2017.

Sony Venice Digital Cinema Camera.

As well as several Sony Venice cameras on the Sony booth, Sony will be holding a special IBC screening of the Venice demo films projected in HDR using Dolby Vision in the main big screen auditorium of the RAI at 2.30pm on Friday. Ed Wild the DP of the UK film will also be there to answer any questions. If you are interested in Sony Venice this should not be missed.

Why are Sony’s ISO’s different between standard gammas and log?

With Sony’s log capable cameras (and most other manufacturers) when you switch between the standard gamma curves and log gamma there is a change in the cameras ISO rating. For example the FS7 is rated at 800 ISO in rec709 but rated at 2000 ISO in log. Why does this change occur and how does it effect the pictures you shoot?

As 709 etc has a limited DR (between around 6 and 10 stops depending on the knee settings) while the sensor itself has a 14 stop range, you only need to take a small part of the sensors full range to produce that smaller range 709 or hypergamma image. That gives the camera manufacturer some freedom to pick the sweetest part of the sensors range. his also gives some leeway as to where you place the base ISO.

I suspect Sony chose 800 ISO for the FS7 and F5 etc as that’s the sensors sweet spot, I certainly don’t think it was an accidental choice.

What is ISO on an electronic camera? ISO is the equivalent sensitivity rating. It isn’t a measure of the cameras actual sensitivity, it is the ISO rating you need to enter into a light meter if you were using an external light meter to get the correct exposure settings. It is the equivalent sensitivity. Remember we can’t change the sensor in these cameras so we can’t actually change the cameras real sensitivity, all we can do is use different amounts of gain or signal amplification to make the pictures brighter or darker.

When you go switch the camera to log you have no choice other than to take everything the sensor offers. It’s a 14 stop sensor and if you want to record 14 stops, then you have to take 100% of the sensors output. The camera manufacturer then chooses what they believe is the best exposure mid point point where they feel there is an acceptable compromise between noise, highlight and lowlight response. From that the manufacture will get an ISO equivalent exposure rating.

If you have an F5, FS7 or other Sony log camera, look at what happens when you switch from rec709 to S-Log2 but you keep your exposure constant.

Middle grey stays more or less where it is, the highlights come down. White will drop from 90% to around 73%. But the ISO rating given by the camera increases from 800ISO to 2000ISO. This increased ISO number implies that the sensor became more sensitive – This is not the case and a little missleading. If you set the camera up to display gain in dB and switch between rec709 (std gamma) and S-Log the camera stays at 0dB, this should be telling you that there is no change to the cameras gain, no change to it’s sensitivity. Yet the ISO rating changes – why?

The only reason the ISO number increases is to force us to underexpose the sensor by 1.3 stops (relative to standard gammas such as rec709 and almost every other gamma) so we can squeeze a bit more out of the highlights. If you were using an external light meter to set your exposure if you change the ISO setting on the light meter from 800 ISO to 2000 ISO  the light meter will tell you to close the aperture by 1.3 stops. So that’s what we do on the camera, we close the aperture down a bit to gain some extra highlight range.

But all this comes at the expense of the shadows and mid range. Because you are putting less light on the sensor if you use 2000 ISO as your base setting the shadows and mids are now not as good as they would be  in 709 or with the other standard gammas.

This is part of the reason why I recommend that you shoot with log between 1 and 2 stops brighter than the base levels given by Sony. If you shoot 1 stop brighter that is the equivalent to shooting at 1000 ISO and this is closer to the 800 ISO that Sony rate the camera at in standard gamma.  Shooting that bit brighter gives you a much better mid range that grades much better.

 

Sony Venice. Full Frame Digital Cinema Camera.

So here it finally is. Sony’s latest digital cinema camera and finally it has a name rather than a number and it’s called Venice.

Sony Venice Digital Cinema Camera.

I was lucky enough to be involved with Venice during the filming of the UK promo film, so I have had a little bit of a chance to play with one, seen it in action in the hands of an experienced DP (Ed Wild B.S.C.) and I have copies of the footage from it (I did the BTS film). So I have a pretty good idea of what we are dealing with…… and it’s good, it’s very, very good.

On-set with Sony’s Venice.

For a long time I have been saying that what we need is better pixels, not more pixels and that’s precisely what Sony have delivered in Venice. The newly developed sensor is a full frame sensor, 36mm x 24mm with 6K’s worth of horizontal pixels. This means that if you use the camera as a super 35mm camera you have 4K (and for the demo films the pre production cameras used only worked at 4K, the equivalent of 35mm 4 perf. 6K will come a little later). Venice will be able to do a huge range of resolutions and aspect ratios including Anamorphic.

Why only 6K? Well it’s down to pixel size. Bigger pixels can capture more light and they can also store more electrons before they overload. This means you get a bigger dynamic range than would typically be possible with smaller pixels. The extra light capturing capability can be used in one of 2 ways, to increase sensitivity or to decrease noise. It appears that the engineers behind Venice went for the latter, lower noise.

There’s a Sony Venice digital cinema camera buried under there somewhere.

A lot of research was done for this camera. Engineers from Japan met with many ASC and BSC cinematographers. They talked to post houses and colourists to find out what was really needed. I know that Claudio Miranda A.S.C. played an important part in the development process, he also shot the US demo film. The end result is a pretty sensitive camera (500 ISO) with very low noise and over 15 stops of dynamic range. Yes – that’s right over 15 stops without resorting to double exposures or any other tricks!!

Left side of the Sony Venice cinema camera.

While the sensor isn’t a global shutter sensor it does have an extremely fast readout rate. This extra fast readout means that jello and other rolling shutter artefacts are minimised to the point where it behaves much more like a global shutter sensor.  Generally speaking, the extra memory circuits needed to get a global shutter either add noise, reduce sensitivity or reduce dynamic range. So it’s not a huge surprise to see the fast read out approach. There was quite a bit of filming done with a rather lovely Lamborghini Uraco, both hand held inside the car and mounted on the front of the car. Looking at the rushes there is no sign of any noticeable rolling shutter artefacts, even the trees flashing past in the background are still nice and vertical.

Viewfinder overlays are now outside of the visible image area.

A lot of the car shooting took place at dusk and an interesting thing that came out of the UK demo reel shoot was how well it performed in low light. The 500 ISO rating is deceptive, because the camera produces so little noise you can rate the camera at a higher ISO and still get good results. Most current cinema cameras don’t produce the best results unless you rate them lower than their base ISO’s. Venice is different, the base ISO is very low noise and very high dynamic range. There appears to be little need to rate it lower for even less noise, although you could if you wish. I asked Ed Wild about this and he was really pleased with Venice’s ISO rating commenting that he often had to rate cameras from other manufacturers lower than the base ISO while he felt Venice at 500 ISO worked really well and that he would even consider rating it higher if needed.

Having a low base ISO means there is less need to use large amounts of ND on outdoor shoots. But talking of ND filters one of the great features of Venice is an 8 stage, behind the lens glass ND filter system. This allows you to choose just the right amount of ND for the light levels you have with no loss of quality. During the pre-shoot test and prep day at Pinewood each stage of the ND was carefully tested for colour shifts and accuracy, no problems were found.

Sony Venice has 2 internal ND filter wheels giving 8 ND levels.

The lens mount on a Venice camera can be changed. It’s not a quick release mount as on the F55 or F5 cameras. It’s normally a PL mount. But the PL mount can be removed and the camera changed to a Sony E-Mount. 6 bolts remove the PL mount and a locking E mount similar to the one on the FS7 II is on the cameras body. This opens up the possibility of using a huge range of lenses, practically anything in fact as it’s easy to adapt from E-Mount to other mounts such as Canon EF for example. For the UK demo reel XTAL Anamorphics from MovieTec were used. Ultra Primes were used for the US promo film.

VENICE A Truly Modular Camera.

Not only can the lens mount be changed but the entire front part of the camera can be changed by removing just 4 screws. Venice is built as a modular camera and the front part of the camera that contains the sensor and ND filters is a removable module (no need for lab conditions or clean rooms to remove the module). This means that in the future Sony could release new sensor options for Venice. Maybe a higher resolution sensor, a monochrome sensor or a high speed sensor. Removing the front sensor module from the camera allows easy access to the cameras internal near silent fan so that it can be cleaned or replaced should that become necessary. All of the cameras electronics are in sealed compartments for dust and moisture protection and rubber seals are installed around any openings such as the SxS card access door. In addition if you do use the AXS-R7 recorder to record Raw/X-OCN this too is weather sealed.

There are 2 SXS card slots on the camera body.

Venice records to SxS cards and with the AXS-R7 attached to AXS cards. You can record XAVC, ProRes HD, ProRes Proxy, as well as Raw/X-OCN. The XAVC recording option allows you to record direct to compact but high quality ready to go files or to record lower resolution proxy files.  X-OCN gives a 16 bit linear workflow with raw type performance but without massive files. There is very little difference between X-OCN and Sony 16 bit linear raw and different versions of X-OCN work at different bit rates so you can pick and choose the right balance of image quality against file size for each project.

Plenty of output options on the Sony Venice camera including 4 x HDSDI/4K SDI and an additional dedicated monitor output.

For Venice Sony have developed new colour science that is designed to emulate film. Looking at the rushes from the camera it really looked nice without any grading. The images contain lots of lush colours. You could see amazing subtle tonal information in the leaves and trees in the shots. Skin tone highlights roll of in a particularly pleasing way.

One of the biggest criticisms of the PMW-F55 and F5 cameras when they were launched was that they were too complex to drive. The F55 menu system is very large containing many, many pages of settings and adjustments. This is a cinema camera without a lot of the fancy modes that cameras like the F5 or F55 have so the menus are simpler straight away. A lot of time was spent trialling different menu structures to determine the easiest and friendliest structure. At the press event during the hands on session most people found it quite easy to navigate around the menus. But really the way the side panel and the quick menu is set up means you won’t need to dive into the main menu very often.

Sony Venice right side.

The camera body is a bit bigger than an F55/F5 and a lot smaller and lighter than an F65. On the right side of the camera there is the main LCD display, which is very similar to the one on the F55/F5 with 6 hot keys around it and a rotary menu dial. This is actually quite similar to the F55’s new Quick Menu system and easy to master.  All the key functions and setup options are just a couple of button presses away. This is the main display and where most of the cameras settings can be changed. It’s on the right side so the AC or DIT can get at it and see it easily. Pressing the user button turns 5 of the 6 buttons around the LCD into user assignable buttons (the 6th button is used to set the assignable functions).

The right side main LCD display and option buttons.

On the left side of the camera there is a small information display that shows the frame rate, shutter speed, ND, ISO and white balance.

The left side information display.

The white balance of the camera can be dialled in manually unlike the F55 you are no longer tied to 3 presets. You can now dial in the white balance you want down to 1 kelvin increments. Once you have set your white balance you can include your new custom setting in the preset list for quick recall at any time.

The camera can run off either 12V or 24V and it has an internal 24V inverter so that when using a 12V power source such as a V-Mount battery you still get 24V out of the industry standard 24V lemo connectors.

The Sony Venice PL mount is secured to the cameras body with 6 bolts. When removed there is a locking E-Mount.

Venice is a modular camera system with various upgrade options. The base camera comes as a 4K super 35mm camera. the 6K option, anamorphic options (6K full frame and 4K 35mm) and other options will be available as option licences. These licences can be purchased as weekly, monthly or permanent options depending on your needs.

What about the picture? I spent a couple of days looking at footage from this camera both in my own grading suite and at Sony’s Pinewood facility during the production of the BTS film. I also saw it projected at the press day and it looks good. One problem today is that there are so many very good and very capable cameras that it’s tough to really pinpoint things that make one stand out as better than another. What I have found to be very pleasing from Venice is the skin tones. Sony have introduced new colour science and colour management for Venice and I think it looks really good. Even before grading, just looking at the clips on a monitor with S-Log3 gamma the pictures have a wonderful rich look. It’s worth noting that the cameras used for both the US and EU launch films were hand made pre-production units and the engineers are still learning how to fully exploit the new sensors in these cameras. So we can only expect them to get better between now and when they become available to buy.

Will I be getting one? Probably not. This is a wonderful camera and I would love to own one, but Venice will be more expensive than the F55 and probably not the best investment for me at least. However I fully intend to get my grubby fingers on one as soon as possible to learn all of it’s in’s and out’s as I hope to use a Venice for some short films I have planned. This is a serious Alexa or Red alternative It has image quality to rival or better almost any other digital cinema camera, but that does come at a price, although it’s no more expensive than any other comparable camera.

The estimated price for the base camera is expected to be around €37,000. Full frame and anamorphic options will be payable options, with the full-frame option costing a approx €4,000 and the anamorphic costing a approx €6,000.  it should be available from around February 2018.

The making of “Fire and Iron”.

I’ve been shooting with the Fujinon MK18-55mm lens on my PXW-FS7 and PXW-FS5 since the lens was launched. I absolutely love this lens, but one thing has frustrated me: I really wanted to be able to use it on my PMW-F5 to take advantage of the 16 bit raw. Finally my dreams have come true as both Duclos and MTF have started making alternate rear mounts for both the MK18-55mm and the MK50-135mm.

Fujinon MK18-55mm on my PMW-F5 using Duclos FZ mount adapter.

So, when Fujinon contacted me and asked if I would be interested in shooting a short film with these lenses on my F5 I jumped at the chance. The only catch was that this was just over a week ago and the video was wanted for IBC which means it needed to be ready yesterday. And of course it goes without saying that it has to look good – no pressure then!

First challenge – come up with something to shoot. Something that would show off the key features of these beautiful lenses – image quality, weight, macro etc. I toyed with hiring a model and travelling to the Irish or Welsh coast and filming along the cliffs and mountains. But it’s the summer holidays so there was a risk of not being able to get an isolated location all to ourselves, plus you never know what the weather is going to do. In addition there was no story, no beginning, middle or end and I really wanted to tell some kind of story rather than just a montage of pretty pictures.

So my next thought was to shoot an artist creating something. I spent a weekend googling various types of artistry until I settled on a blacksmith. The video was going to be shown in both SDR and HDR and fire always looks good in HDR. So after dozens of emails and telephone calls I found an amazing looking metalwork gallery and blacksmith that was willing for a reasonable fee to have me and another cameraman take over their workshop for a day (BIG thank you to Adam and Lucy at Fire and Iron check out their amazing works of art).

A blacksmiths forge and art gallery were chosen for the shoot.

Normally I’d carry out a recce of a location before a shoot to take photos and figure out what kind of lights I would need as well as any other specialist or unusual equipment. But this time there simply wasn’t time. We would be shooting the same week and it was already a very busy week for me.

The next step before any shoot for me is some degree of planning. I like to have a concept for the video, at the very least some outline of the shots I need to tell the story, perhaps not a full storyboard, but at least some kind of structure. Once you have figured out the shots that you want to get you can then start to think about what kind of equipment you need to get those shots. In this case, as we would be shooting static works of art I felt that having ways to move the camera would really enhance the video. I have a small Jib as well as some track and a basic dolly that is substantial enough to take the weight of a fully configured PMW-F5 so these would be used for the shoot (I’m also now looking for a slider suitable for the F5/F55 that won’t break the bank, so let me know if you have any recommendations).

My PMW-F5 with Fujinon MK18-55mm zoom fitted with Duclos FZ mount.

So the first items on my kit list after the camera and lenses (the lenses were fitted with Duclos FZ rear mounts) was the jib and dolly. To achieve a nice shallow depth of field I planned to shoot as close to the lenses largest aperture of T2.9 as possible. This presents 2 challenges. The F5’s internal ND filters go in 3 stop steps – that’s a big step and I don’t want to end up at T5.6 when really I want T2.9, so 1 stop and 2 stop ND filters and my gucchi wood finished Vocas matte box would be needed (the wood look does nothing to help the image quality, but it looks cool). Oh for the FS7 II’s variable ND filter in my F5!

The second problem of shooting everything at T2.9 with a super 35mm sensor is that focus would be critical and I was planning on swinging the camera on a jib. So I splashed out on a new remote follow focus from PDMovie as they are currently on offer in the UK. This is something I’ve been meaning to get for a while. As well as the remote follow focus I added my Alphatron ProPull follow focus to the kit list. The Fujinon MK lenses have integrated 0.8 pitch gears so using a follow focus is easy. I now wish that I had actually purchased the more expensive PDMovie follow focus kit that has 2 motors as this would allow me to electronically zoom the lens as well as focus it. Oh well, another thing to add to my wish list for the future.

One other nice feature of the Fujinon MK’s is that because they are parfocal you can zoom in to focus and then zoom out for the wider shot and be 100% sure that there is no focus shift and that the image will be tack sharp. Something you can’t do with DSLR lenses.

The PDMovie follow focus motor engages perfectly with the pitch gears on the Fujinon MK series lenses.

Lighting: This was a daylight shoot. Now I have to say that I am still a big fan of old school tungsten lighting. You don’t get any odd color casts, it gives great skin tones, it’s cheap and the variety and types of lamp available is vast. But as we all know it needs a lot of power and gets hot. Plus if you want to mix tungsten with daylight you have to use correction gels which makes the lights even less efficient. So for this shoot I packed my Light and Motion Stella lamps.

Light and Motion Stella lamp fitted with 25 degree fresnel lens.

The Stellas are daylight balanced LED lamps with nice wide 120 degree beams. You can then use various modifiers to change this. I find the 25 degree fresnel and the Stella 5000 a particularly useful combination. This is the equivalent to a 650W tungsten lamp but without the heat. The fresnel lens really helps when lighting via a diffuser or bounce as it controls the spill levels making it easier to control the overall contrast in the shot. The Stella lights have built in batteries or can be run from the mains. They are also waterproof, so even if it rained I would be able to have lights outside the workshop shining in through the windows if needed.

I always carry a number of pop-up diffusers and reflectors of various sizes along with stands and arms specifically designed to hold them. These are cheap but incredibly useful. I find I end up using at least one of these on almost every shoot that I do. As well as a couple of black flags I also carry black drapes to place on the floor or hang from stands to reduce reflections and in effect absorb unwanted light.

Atomos Shogun Flame being used to check exposure and focus.

To check my images on set I use an Atomos Shogun Flame. Rather than mounting it on the camera, for this shoot I decided to pack an extra heavy duty lighting stand to support the Shogun. This would allow my assistant to use the flame to check focus while I was swinging the jib. The HDR screen on the Shogun allows me to see a close approximation of how my footage will look after grading. It  also has peaking and a zoom function to help with focussing which was going to be essential when the camera was up high on the jib and being focussed remotely. I also included a TV-Logic LUM171G which is a 17″ grading quality monitor with 4K inputs. The larger screen is useful for focus and it’s colour accuracy helpful for checking exposure etc.

For audio I packed my trusty UWP-D wireless mic kit and a pair of headphones. I also had a shotgun mic and XLR cable to record some atmos.

As well as all the larger items of kit there’s also all the small bits and bobs that help a shoot go smoothly. A couple of rolls of gaffer tape, crocodile clips, sharpies, spare batteries, extension cables etc. One thing I’ve found very useful is an equipment cart. I have a modiffied rock-n-roller cart with carpet covered shelves. Not only does this help move all the kit around but it also acts as a desk on location. This is really handy when swapping lenses or prepping the camera. It can save quite a bit of time when you have a mobile work area and somewhere you can put lenses and other frequently used bits of kit.

The day before the shoot I set everything up and tested everything. I checked the backfocus adjustment of the lenses. Checked the camera was working as expected and that I had the LUT’s I wanted loaded into both the camera and the Gratical viewfinder. With the camera on the jib I made sure I had the right weights and that everything was smooth. I also checked that my light meter was still calibrated against the camera and that the lens apertures matched what I was expecting (which they did perfectly). Color temperature and colorimetry was checked on the TVLogic monitor.

It’s worth periodically checking these things as there would be nothing worse than rocking up for the shoot only to find the camera wasn’t performing as expected. If you rent a cinema camera package from a major rental house it would be normal to set the camera up on a test bench to check it over before taking it away. But it’s easy to get lazy if it’s your own kit and just assume it’s all OK. A full test like this before an important shoot is well worth doing and it gives you a chance to set everything up exactly as it will be on the shoot saving time and stress at the beginning of the shoot day.

On the morning of the shoot I loaded up the car. I drive a people carrier (minivan to my friends in the USA). Once you start including things like a jib, track and dolly, equipment cart, 6x tungsten lights, 4 x LED lights, plus camera, tripods (including a very heavy duty one for the jib) the car soon fills up. A conventional saloon would not be big enough! One word of caution. I was involved in a car crash many years ago when the car rolled over. I had camera kit in the back of the car and the heavy flight cases did a lot of damage crashing around inside the car. If you do carry heavy kit in the car make sure it’s loaded low down below the tops of the seats. You don’t want everything flying forwards and hitting you on the back of your head in a crash. Perhaps consider a robust steel grill to put between the cargo compartment and the passenger compartment.

On arrival at the location, while it’s very tempting to immediately start unloading and setting up, I like to take a bit of a break and have a tea or coffee first. I use this time to chat with the client or the rest of the crew to make sure everyone knows what’s planned for the day. Taking a few minutes to do this can save a lot of time later and it helps everyone to relax a little before what could be a busy and stressful day.

Now it’s time to unpack and setup. I find it’s better to unpack all the gear at this time rather than stopping and starting throughout the day to unpack new bits of kit. Going to the car, unlocking, unpacking, locking, back to the set etc wastes time. This is where the equipment cart can be a big help as you can load up the cart with all those bits and pieces you “might” need… and inevitably do need.

The blacksmiths workshop. A small dark space.

The blacksmiths workshop was a dark space about 6m x 5m with black walls, open on one side to the outside world.  Blacksmiths forges (so I learnt) are dark so that the blacksmith can see the glow of the metal as it heats up to gauge it’s temperature. On the one hand this was great – huge amounts of relatively soft light coming from one direction. On the other hand the dark side was very dark which would really push the camera and lenses due to the extreme contrast this would create.

The seven blacksmithing processes. Frame grab from the film.

We set the jib up inside the workshop to shoot the various processes used by a blacksmith when working with iron and steel. Apparently there are only 7 different processes and anything a blacksmith does will use just these 7 processes or variations of them.

A small jib was used for much of the shoot.

Most of the shots done on the jib would be shot using the Fujinon MK18-55mm, so that’s the lens we started with. For protection from flying sparks a clear glass filter was fitted to the lens. While the finished film would be a 24p film, most of the filming was 4K DCI at 60fps recording to 16 bit raw. This would give me the option to slow down footage to 24p in post if I wanted a bit of slow motion.

When we did need to do a lens swap it was really easy. The Vocas matte box I have is a swing-away matte box. So by releasing a lever on the bottom of the matte box it swings out of the way of the lens without having to remove it from the rods. Then I can remove the lens and swap it to the other lens. The MK50-135mm is the same size as the MK18-55mm. The pitch gears are also in the same place. So swapping lenses is super fast as the follow focus or any focus motors don’t need to be re-positioned and the matte box just swings back to exactly the same position on the lens. It’s things like this that really separate pro cinema lenses from DSLR and photography lenses.

My wood effect Vocas swing away matte box.

For exposure I used the cameras built in LUT’s and the 709(800) LUT. I set the camera to 800EI. I used a grey card to establish a base exposure, exposing the grey card at 43% (measuring the 709 level). I used a Zacuto Gratical viewfinder which has a great built in waveform display, much better than the one in the camera. I also double checked my light levels with a light meter. I don’t feel that it’s essential to use a light meter but it’s a useful safety net. The light meter is also handy for measuring contrast ratios across faces etc but again if you have a decent waveform display you don’t have to have a light meter.

For the next 3 hours we shot the various processes seen in the video. Trying to get a variety of different shot. But when each process is quite similar, usually involving the anvil and a large hammer it was difficult to come up with shots that looked different.

Getting ready for a close up on the Anvil.

In the afternoon we set up to shoot the interview sequence. The reason for doing this was to not only provide the narrative for the film but also to help show how the lenses reproduce skin tones. The Fujinon MK series lenses are what I would describe as “well rounded”.  That is, not too sharp but not soft either. They produce beautifully crisp pictures without the pictures looking artificially sharp and this really helps when shooting people and faces. They just look really nice.

Shooting the interview sequence.

For the interview shot I used one of the Stella 5000 lights with the 25 degree fresnel lens aimed through a 1m wide diffuser to add a little extra light to supplement the daylight. This allowed me to get some nice contrast across the blacksmiths face and nice “catch light” highlights in his eyes. In addition the little bit of extra light on his face meant that the back wall of the forge would appear just that bit darker due to the increased contrast between his face and the back wall. This is why we light…. not just to ensure enough light to shoot with, I had plenty of light, if I remember right I had a 1 stop ND in the matte box. But to create contrast, it’s the contrast that gives the image depth, it’s contrast that makes an image look interesting.

Last setup of the day shooting the metal artworks. Using a gold reflector and Stella 5000 lamp to add some punch and drama to the shots.

The final stage was to shoot the treasure chest and ornate jars that would show off the the lenses macro and close up performance. The treasure chest is a truly amazing thing. It weighs around 80kg. The locking mechanism is quite fascinating and I still struggle to believe that it was all hand made. The small metal jars are made out of folded and welded steel. It’s the folds in the metal that create the patterns that you see.

Once again we used the jib to add motion to the shots. I also used the macro function of both the MK18-55mm and MK50-135mm lenses. This function allows you to get within inches of the object that you are shooting. It’s a great feature to have and it really adds to the versatility of these lenses.

The Zacuto Gratical has a much better waveform display than the cameras own, so it’s a useful viewfinder to have.

We wrapped at 7pm. Time to pack away the kit. It’s really important not to rush at this stage. Like everyone else I want to get home as quick as I can. But it’s important to pack your kit carefully and properly. There is nothing more annoying than when you start prepping for the next shoot finding that something has been broken or is missing because you rushed to pack up at the end of the previous shoot. Once you have packed everything away don’t forget to do that last walk through all the locations you’ve shot in to make sure you haven’t forgotten something.

I shot a little over hour of material. As it was mostly 60p 4K raw that came to about 1.5TB This was backed up on site using a Nexto-DI NSB25 which is a stand alone device that makes 2 verified copies of everything on 2 different hard drives. The film was edited using Adobe Premiere CC which handles Sony’s raw very easily. Grading was completed using DaVinci Resolve. I spent 2 days editing and a day grading the first version of the film. Then I spent another day re-grading it for HDR and producing the different versions that would be needed. All in, including coming up with the concept, finding the location, prepping, shooting and post took it took about 7 to 8 full work days to put this simple 4 minute film together.

Here’s the behind the scenes video