Sony have just released the latest version of their free viewing, copying and transcoding software Catalyst Browse and the more fully featured paid software Catalyst Prepare. These new versions includes support for the PXW-FX9’s metadata based image stabilisation. Hopefully the new Mac versions are also optimised for Catalina.
This is something a lot of people have been asking for. An extension or relocation cable that allows you to place devices that will be connected to a camera via the MI Shoe away from the shoe itself.
But in order to get the MI Shoe relocation cable you have to buy the whole XLR-K3M XLR adapter kit, you can’t get the cable on it’s own. This is a shame as I would like to use the cable with my UWP-D series radio mics. I’m not a fan of having the radio mic receiver right on top of the handle as it tends to stick out and get in the way when you put the camera into most camera bags. But, I don’t really need the XLR adapter.
Anyway, here’s a link to the XLR-K3M for those that really need that cable (or the new XLR adapter).
A completely useless bit of trivia for you is that the “E” in E-mount stands for eighteen. 18mm is the E-mount flange back distance. That’s the distance between the sensor and the face of the lens mount. The fact the e-mount is only 18mm while most other DSLR systems have a flange back distance of around 40mm means thare are 20mm or more in hand that can be used for adapters to go between the camera body and 3rd party lenses with different mounts.
Here’s a little table of some common flange back distances:
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:
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:
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:
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.
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:
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.
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”:
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:
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.
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.
it, camera base plates are not really very exciting things. But they are very
necessary additions to most peoples kit, especially for any of the full size
super 35mm digital cinema cameras. From Red’s to F55’s to FS7 etc, they will
almost always need some form of base plate at some point.
So what’s different about the Vocas sliding system?
A complete Vocas sliding base plate system comprises two main parts. The first bit attaches to the camera and that will be either a generic flat camera mounting adapter plate or a custom camera mounting plate for cameras that don’t have flat bases, for example the FS7 or Venice where the adapter follows the curve or shape of the bottom of the camera.
The second part is a shoulder mount, shoulder pad or tripod plate or generic flat mounting plate that the camera adapter smoothly and securely slides onto.
One of the first benefits of this system is that you can easily alter the position of the camera relative to the base plate or shoulder pad. This makes balancing the camera on your shoulder or on a tripod much easier. A large red level locks the two sliding parts securely in place and there is a safety release catch that must be pressed if you wish to separate the mounting plate from the base plate, so they can’t come apart by accident. However if you need to move the camera forwards or backwards relative to the mounting plate all you need to do is release the large red locking lever.
Another benefit of the system is that it is very quick to reconfigure if you need to. For example many cinematography accessories are mounted using 19mm rails rather than the lightweight 15mm rails often used with ENG or smaller rigs. Perhaps you have been shooting handheld where a lightweight 15mm setup works better. Using the Vocas sliding system you can have a light weight base plate with a comfortable shoulder pad, 15mm front and rear rails that will clip in and out of a VCT style quick release tripod plate attached to the camera for your handheld shots. Then when you need to go to a bigger lens perhaps and 19mm rods, you simply slide off the 15mm base plate and slide on the Vocas 19mm plate. Quickly transforming the camera into a heavy duty rig that will then attach to an Arri style tripod plate. Need to keep the 19mm rods but now need a shoulder pad? Well that’s easy too as there is a matching shoulder pad for the 19mm base plate. It’s all very quick and very easy.
It also means that if you have multiple cameras all you is a mounting plate on each of your cameras then you can use the same base plate on all your cameras just by sliding it on and off as needed, or swap between lot’s of different types of plates depending on your needs.
If you don’t need a base plate with rods etc and just need a quick way to mount your camera to a tripod then there is also a basic tripod adapter that the camera can be slid directly onto. This gives you a really secure, quick release, low profile mounting system that is free from the wobble that often plagues other quick release mounts. It’s ideal for crash cams, car mounts and car rigs. Or for those situations where you just need something quick and compact. This would also help keep the weight down for use on gimbals or perhaps a stedicam. Need to go back to a shoulder mount or full tripod rig with rods, just slide the camera off the tripod plate and slide it on to your preferred 15mm or 19mm shoulder plate.
Nice touches on the VCT type base plates are the adjustable height rod mounts and also an adjustable tensioner for the rear mounting spigot. Normally on a VCT base plate the rear spigot doesn’t do a great deal to add stability to the system, it just helps to loosely locate the base plate. However Vocas have added the ability to put some tension on to the rear spigot to help pull the camera down onto the VCT plate. This can greatly decrease, if not eliminate the wobble and flex that is all to common with these quick release plates.
really nice touch is that the attachment screws for the mounting plate and an
allen key for adjusting the height of the rod mounts can be stored inside the
base plate so you should never loose them.
Any downsides? Well yes, any 2 part system like this is going to be a little more complex with more parts and a bit more metal than a basic fixed mounting plate, so the sliding base plate ends up a touch heavier than the equivalent fixed position base plate. It’s not a big difference, but it does add a bit of weight. However in most cases I believe it’s worth it. Especially if you are swapping between 15mm and 19mm systems frequently. Being able to quickly and easily re-balance the camera when handheld and you change lenses is very nice.
If you have more than one camera it makes it easier to share different mounting systems between them. So while the initial cost may be a bit more, in the long run you only ever need to add new mounting adapters to keep using all the different base plates you have with extra cameras or new cameras.
As always with Vocas products the quality of the engineering is first class. The parts fit together beautifully. Only high quality materials are used and the finish is very nice. So if you are looking for a really nice base plate for your camera – or cameras – do take a look at the Vocas sliding system. It’s really very well thought out and something that will last for a very long time.
I have a good relationship with the guys at Vocas. I had been shown this system
at various trade shows and it looked interesting, so I approached Vocas for the
loan of a review system so I could write this article.
Following a series of recent discussions about whether or not it was possible to recover files from XQD cards that have been formatted by mistake I have obtained some clarification from Sony of what can or can’t be done.
This information is specifically for XQD cards and the PXW-FS7 but probably applies to most Sony cameras and also SxS media. I’m not sure about SD cards.
The bottom line is that if you format the card in the camera you will not be able to recover any previously shot material. An in-camera format completely erases everything on the card. This is done to ensure that material shot on the cards cannot be recovered by another production company in the case of card or camera rentals. So there is no point in attempting any form of data recovery on a card formatted in the camera as there is nothing recoverable left on the card.
Formatted by a computer:
When you format a card with a computer it is possible that the material will still be on the card. However different operating systems handle the formatting of the cards differently, so there is no guarantee that the data will be recoverable and often it won’t be recoverable. For very important material it may be worth attempting to recover the card. Sony may be able to assist with this in some cases.
Clips deleted from a card can typically be recovered provided they have not be recorded over by a later recording. Again Sony may be able to assist with this.
Delete or Format?
Based on this new information from Sony I may be adjusting my workflow. My own workflow has always been to off-load material from a card. Then to do a parity check to compare the original files on the card and what is now on the hard drives. This checks not just the file size but also the general structure of the files so should pick up most problems with any copies. My last check is then to skim through the files with Catalyst Browse or my edit application to make sure the clips are there and playable. Only then do I format a card. In light of this new information I may use my computer to delete the clips from a card rather than format it. Of course this will only ever offer some benefit if the card is not recorded on again causing the previous files to be over written, but it might add an extra chance of data recovery should the backups get lost or some other disaster occur. From time to time I would format the cards in camera as this helps keep the cards in the best possible condition.
“Color Science” is one of those currently in fashion phrases that gets thrown around all over the place today. First of all – what the heck is color science anyway? Simply put it’s how the camera sees the colors in a scene, mixes them together, records them – and then how your editing or grading software interprets what is in the recording and finally how the TV or other display device turns the digital values it receives back into a color image. It’s a combination of optical filters such as the low pass filter, color filters, sensor properties, how the sensor is read out and how the signals are electronically processed both in the camera, by your edit/grading system and by the display device. It is no one single thing, and it’s important to understand that your edit process also contributes to the overall color science.
Color Science is something we have been doing since the very first color cameras, it’s not anything new. However us end users now have a much greater ability to modify that color science thanks to better post production tools and in camera adjustments such as picture profiles or scene files.
Recently, Sony cameras have sometimes been seen by some as having less advanced or poor color science compared to cameras from some other manufacturers. Is this really the case? For Sony part of the color science issue is that historically Sony have deliberately designed their newest cameras to match previous generations of cameras so that a large organisation with multiple cameras can use new cameras without having them look radically different to their old ones. It has always been like this and all the manufacturers do this, Panasonic cameras have a certain look as do Canon etc. New and old Panasonics tend to look the same as do old and new Canon’s, but the Canon’s look different to the Panasonics which look different to the Sony’s.
Sony have a very long heritage in broadcast TV and that’s how their cameras look out of the box, like Rec-709 TV cameras with colors that are similar to the tube cameras they were producing 20 years ago. Sony’s broadcast color science is really very accurate – point one at a test chart such as a Chroma DuMonde and you’ll see highly repeatable, consistent and accurate color reproduction with all the vectors on a vector scope falling exactly where they should, including the skin tone line.
On the one hand this is great if you are that big multi-camera business wanting to add new cameras to old ones without problems, where you want your latest ENG or self-shooters cameras to have the same colors as your perhaps older studio cameras so that any video inserts into a studio show cut in and out smoothly with a consistent look.
But on the other hand it’s not so good if you are a one man band shooter that wants something that looks different. Plus accurate is not always “pretty” and you can’t get away from the fact that the pictures look like Rec-709 television pictures in a new world of digital cinematography where TV is perhaps seen as bad and the holy grail is now a very different kind of look that is more stylised and much less true to life.
So Sony have been a bit stuck. The standard look you get when you apply any of the standard off-the shelf S-Log3 or S-Log2 LUT’s will by design be based on the Sony color science of old, so you get the Sony look. Most edit and grading applications are using transforms for S-Log2/3 based on Sony’s old standard Rec-709 look to maintain this consistency of look. This isn’t a mistake. It’s by design, it’s a Sony camera so it’s supposed to look like other Sony cameras, not different.
But for many this isn’t what they want. They want a camera that looks different, perhaps the “film look” – whatever that is?
Recently we have seen two new cameras from Sony that out of the box look very different from all the others. Sony’s high end Venice camera and the lower cost FS5 MKII. The FS5 MKII in particular proves that it’s possible to have a very different look with Sony’s existing colour filters and sensors. The FS5 MK II has exactly the same sensor with exactly the same electronics as the MK I. The only difference is in the way the RGB data from the sensor is being processed and mixed together (determined by the different firmware in the Mk1 and mk2) to create the final output.
The sensors Sony manufacture and use are very good at capturing color. Sony sensors are found in cameras from many different manufacturers. The recording systems in the Sony cameras do a fine job of recording those colors as data within the files the camera records as data with different code values representing what the sensor saw. Take that data into almost any half decent grading software and you can change the way it looks by modifying the data values. In post production I can turn almost any color I want into any other color. It’s really up to us as to how we translate the code values in the files into the colors we see on the screen, especially when recording using Log or raw. A 3D LUT can change tones and hues very easily by shifting and modifying the code values. So really there is no reason why you have to have the Sony 709 look.
My Venice emulation LUT’s will make S-Log3 from an FS5 or FS7 look quite different to the old Sony Broadcast look. I also have LUT’s for Sony cameras that emulate different Fuji and Kodak film stocks, apply one of these and it really looks nothing like a Sony broadcast camera. Another alternative is to use a color managed workflow such as ACES which will attempt to make just about every camera on the market look the same applying the ACES film style look and highlight roll-off.
We have seen it time and time again where Sony footage has been graded well and it then becomes all but impossible to identify what camera shot it. If you have Netflix take a look at “The Crown” shot on Sony’s F55 (which has the same default Sony look as the FS5 MK1, FS7 etc). Most people find it hard to believe the Crown was shot with a Sony because it has not even the slightest hint of the old Sony broadcast look.
If you use default settings, standard LUT’s etc it will look like a Sony, it’s supposed to! But you have the freedom to choose from a vast range of alternative looks or better still create your own looks and styles with your own grading choices.
But for many this can prove tricky as often they will start with a standard Sony LUT or standard Sony transform. So the image they start with has the old Sony look. When you start to grade or adjust this it can sometimes look wrong because you have perhaps become used to the original Sony image and then anything else just doesn’t seem right, because it’s not what you are used to. In addition if you add a LUT and then grade, elements of the LUT’s look may be hard to remove, things like the highlight roll off will be hard baked into the material, so you need to do need to think carefully about how you use LUT’s. So try to break away from standard LUT’s. Try ACES or try some other starting point for your grade.
Going forward I think it is likely that we will see the new Venice look become standard across all of the Cinema style cameras from Sony, but it will take time for this to trickle down into all the grading and editing software that currently uses transforms for s-Log2/3 that are based on the old Sony Rec-709 broadcast look. But if you grade your footage for yourself you can create just about any look you want.
This was asked for on one of the online groups I follow. It’s a simple Black and White LUT that gives a wide dynamic range black and white image. The LUT has been designed to give a pleasing and gentle highlight roll-off with a reasonably contrasty mid range. I decided not to go too contrasty via the LUT so that more contrast can be added in post if needed. The output is legal range (broadcast safe). There is a single camera LUT for use in camera as well as a set of exposure compensated LUT’s going from -2 to plus 2 stops in half stop steps.
As always (to date at least) I offer these as a free download available by clicking at the bottom of the page. It takes time to create them and money to host them. I feel that this LUT set is worth $5.00 and would really appreciate that being paid if you find the LUT’s useful. But I will let you pay what you feel is fair, all contributions are greatly appreciated and it really does help keep this website up and running. If you can’t afford to pay, then just download the LUT’s and enjoy using them. If in the future you should choose to use them on a paying project, please remember where you got them and come back and make a contribution. More contributions means more LUT offerings in the future.
Please feel free to share a link to this page if you wish to share these LUT’s with anyone else or anywhere else.
To make a contribution please use the drop down menu here, there are several contribution levels to choose from.
I’ve uploaded these LUT’s before, but they are tucked away under a slightly obscure heading, so here they are again!
There are 4 different LUTs in this set. A basic 709 LUT which is really good for checking exposure etc. It won’t give the best image, but it’s really good for getting your exposure just right. Diffuse white should be 85%, middle grey 43% and skin tones 65-70%.
Then there are 3 film emulation LUT’s that mimic 3 different types of film stock form different manufacturers. These are primarily designed for post production or for use on a client monitor on set. My recommendation is to use the 709 LUT for your viewfinder and exposure and then add the film emulation LUT later in post.
As always (to date at least) I offer these as a free download available by clicking on the links below. However a lot of work goes into creating and hosting these. I feel that this LUT set is worth $25.00 and would really appreciate that being paid if you find the LUT’s useful. Try them before you decide then pay what you feel is fair. All contributions are greatly appreciated and it really does help keep this website up and running. If you can’t afford to pay, then just download the LUT’s and enjoy using them, tell your friends and send them here. If in the future you should choose to use them on a paying project, please remember where you got them and come back and make a contribution. More contributions means more LUT offerings in the future.
There are a lot of videos circulating on the web right now showing what appears to be some kind of magic trick where someone has shot over exposed, recorded the over exposed images using ProRes Raw and then as if by magic made some adjustments to the footage and it goes from being almost nothing but a white out of over exposure to a perfectly exposed image.
This isn’t magic, this isn’t raw suddenly giving you more over exposure range than you have with log, this is nothing more than a quirk of the way FCP-X handles ProRes Raw material.
Before going any further – this isn’t a put-down of raw or ProRes raw. It’s really great to be able to take raw sensor data and record that with only minimal processing. There are a lot of benefits to shooting with raw (see my earlier post showing all the extra data that 12 bit raw can give). But a magic ability to let you over expose by seemingly crazy amounts isn’t something raw does any better than log.
Currently to work with ProRes Raw you have to go through FCP-X. FCP-X applies a default sequence of transforms to the Raw footage to get it from raw data to a viewable image. These all expect the footage to be exposed exactly as per the camera manufacturers recommendations, with no leeway. Inside FCP-X it’s either exposed exactly right, or it isn’t.
The default decode settings include a heavy highlight roll-off. Apple call it “Tone Mapping”. Fancy words used to make it sound special but it’s really no different to a LUT or the transforms and processes that take place in other raw decoders. Like a LUT it maps very specific values in the raw data to very specific output brightness values. So if you shoot just a bit bright – as you would often do with log to improve the signal to noise ratio – The ProRes raw appears to be heavily over exposed. This is because anything bright ends up crushed into nothing but flat white by the default highlight roll off that is applied by default.
In reality the material is probably only marginally over exposed, maybe just one to 2 stops which is something we have become used to doing with log. When you view brightly exposed log, the log itself doesn’t look over exposed, but if you apply a narrow high contrast 709 LUT to it, it then the footage looks over exposed until you grade it or add an exposure compensated LUT. This is what is happening by default inside FCP-X, a transform is being applied that makes brightly exposed footage look very bright and possibly over exposed – because thats the way it was shot!
This is why in FCP-X it is typical to change the color library to WCG (Wide Color Gamut) as this changes the way FCP-X processes the raw, changing the Tone Mapping and most importantly getting rid of the highlight roll off. With no roll-off, highlights and any even slight over exposure will still blow out as you can’t show 14 stops on a conventional 6 stop TV or monitor. Anything beyond the first 6 stops will be lost, the image will look over exposed until you grade or adjust the material to control the brighter parts of the image and bring them back into a viewable range. When you are in WCG mode in FCP-X the there is no longer a highlight roll off crushing the highlights and now because they are not crushed they can be recovered, but there isn’t any more highlight range than you would have if you shot with log on the same camera!
None of this is some kind of Raw over exposure magic trick as is often portrayed. It’s simply not really understanding how the workflow works and appreciating that if you shoot bright – well it’s going to look bright – until you normalise it in post. We do this all the time with log via LUT’s and grading too! It can be a little more straight forward to recover highlights from Linear Raw footage as comes form an FS5 or FS7 compared to log. That’s because of the way log maintains a constant data level in each highlight stop and often normal grading and colour correction tools don’t deal with this correctly. The highlight range is there, but it can be tricky to normalise the log without log grading tools such as the log controls in DaVinci Resolve.
Another problem is the common use of LUT’s on log footage. The vast majority of LUT’s add a highlight roll off, if you try to grade the highlights after adding a LUT with a highlight roll off it’s going to be next to impossible to recover the highlights. You must do the highlight recovery before the LUT is added or use a LUT that has compensation for any over exposure. All of these things can give the impression that log has less highlight range than the raw from the same camera. This is not normally the case, both will be the same as it’s the sensor that limits the range.
The difference in the highlight behaviour is in the workflows and very often both log and raw workflows are miss-understood. This can lead to owners and users of these cameras thinking that one process has more than the other, when in reality there is no difference, it’s appears to be different because the workflow works in a different way.
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