Category Archives: A7

Fixing Hot or Bright Pixels On the Sony FX3

The FX3’s larger brothers, the FX6 and FX9 have a function called “APR” that is used to periodically inspect every pixel on the sensor and normalise or map out any out of spec pixels. With modern 4K cameras having at least 8.8 million pixels the chances of a few going out of spec or being damaged by cosmic rays from time to time is quite high. So on the FX6 and FX9 you will get a reminder to perform the APR process around once a week.

From what I understand, the Alpha series cameras and FX3 also periodically perform a similar process automatically. Because these camera have a mechanical shutter to shut out any external light there is no need for any user intervention to perform this process so you will not be aware that it’s happening. On the FX6 and FX9 the user has to place a cap over the lens or sensor, hence why the camera asks you before it can happen.

But what if you find you have some bright or hot pixels with the FX3? Perhaps you have just travelled on a plane where the high altitude reduces the atmospheres damping effect of the high energy particles from space that can damage pixels. Well you can go into the camera’s menu system and force it to run its pixel mapping process which does the same thing as APR on the other cameras.

You need to go to:

MENU:  (Setup) ? [Setup Option] ? select [Pixel Mapping] and then select OK.  It doesn’t take long and I would recommend that you do this after flying on a plane or prior to any shoot where you will use large amounts of gain as this is when hot pixels are most likely to show up.

Understanding Sony’s Viewfinder Display Gamma assist.

Most of sony’s cameras that support S-Log3 or Hybrid Log Gamma also have a function called Viewfinder Display Gamma Assist.

Viewfinder Display Gamma Assist allows you to monitor with the cameras built in LCD screen or viewfinder with the correct brightness and contrast range when using gamma curves that are not directly compatible with these Rec-709 screens.

Whenever you try to view a gamma curve that is not normal Rec-709 on a Rec-709 screen the brightness and contrast that you will see will be incorrect. The most common scenario is perhaps viewing S-Log3 without any form of LUT. In this case the images will look less bright and have less contrast than they should and this makes judging exposure difficult and as well as making it less easy to see focus errors.

With a camera like the FX6 or FX9 most people will use the cameras CineEI mode and add a LUT to the viewfinder image to convert the S-Log3 to something that looks more contrasty and on the FX6 and FX9 the default LUT is “s709”.  However s709 is not the same thing as Rec-709.

I think a lot of people think that the default s709 LUT is the same as Rec-709, it’s not, it is very different. They look very different and result in quite different brightness levels when exposed correctly. s709 when exposed correctly will put skin tones somewhere around 50-60% and white at 78%. If you expose s709 using normal Rec-709 brightness levels (70% skintones, 90% white) this is actually over exposed by just over 1 stop. As a result if you expose the s709 LUT, using Rec-709 levels, and then turn off the LUT and instead use Viewfinder Gamma Assist, the gamma assist will look wrong, it will be too bright and may look washed out and this is simply because the exposure IS wrong.

Almost always, if the viewfinder display gamma assist looks wrong, the exposure is wrong. When it looks right, the likelihood is the exposure is right.

A few things to understand:
  • The viewfinder is a Rec-709 range display device only capable of showing Rec-709 range and colour.
  • Feed true Rec-709 to a Rec-709 device and you will have a correct looking image with “normal” brightness, contrast and colour.
  • Feed S-Log3 to a Rec-709 device and you will have an incorrect dull, flat looking image due to the gamma miss-match between the capture gamma and display gamma.
  • Feed S-Log3 to a device with S-Log3 gamma and you will once again have the correct brightness and contrast as there is no longer a gamma miss-match (S-Log3 only appears to be flat due to the gamma missmatch between S-Log3 and Rec-709, use the right gamma and you will see that it is not actually flat).

Viewfinder Display Gamma Assist works by changing the gamma curve used in the Viewfinder to a gamma curve similar to S-Log3. When you view S-Log3 with S-Log3 gamma you will have the correct contrast and brightness, so correct exposure will look correct.

But because the cameras LCD display screen can only show 6 to 7 stops you don’t get the full S-Log3 viewing range, just the central mid range part that is the direct equivalent of Rec-709. This very closely matches what you see if you use the Sony 709(800) LUT to convert the S-log3 to 709. The 709(800) LUT converts S-Log2 or S-Log3 to vanilla Rec-709 (70% skintones/90% white) with a knee that provides a slightly extended highlight range. It is broadly comparable to how most conventional Rec-709 cameras will look. So as a result viewfinder display gamma assist and Sony’s 709(800) LUT’s will look almost identical, while the s709 LUT will (and should by design) look different.


Viewfinder Display Gamma Assist is extremely useful for scenarios where you do not have a LUT option. It can help you make good exposure assessments. It can make it easier to see when you are in focus. But it isn’t a LUT, so can’t be applied to the cameras outputs, only the built in viewfinder. Additionally if you use zebras, the waveform or histogram, gamma assist has no effect on these so you must remember that you are still measuring the levels f the actual recording gamma, not Rec-709 levels.

Viewfinder Gamma Assist is useful not only for shooting with S-Log but also when shooting using HLG (Hybrid Log Gamma). HLG is an HDR gamma curve and because the LCD viewfinder isn’t HDR you can’t correctly monitor HLG directly. Viewfinder Gamma Assist allows you to monitor with the correct brightness and contrast when shooting HLG making it easier to confidently get the correct exposure levels, as much like S-log3 the levels required for the correct exposure of HLG are quite different to Rec-709.

One last thing: NEVER use Viewfinder Gamma Assist with a LUT at the same time, this will result in a completely incorrect looking image and could result in very bad exposure as a result.

Which Sony ISO RatingS Are Correct?

In the course of my tests with the FX3 and comparing it with the FX6 and FX9 I discovered a strange anomaly with the FX3 and A7SIII ISO ratings when compared to the FX6 and FX9. 


The FX3’s default picture profile is PP11 and S-Cinetone. If you have an FX6 or FX9 these cameras also default to S-Cinetone in SDR mode. In the FX6 and FX9 the base ISO for S-Cinetone is 320 ISO. Therefore you would assume that if you also set the A7SIII or the FX3 to 320 ISO and expose all the cameras the same, same aperture, shutter etc that the exposures would match.

BUT THE EXPOSURES DON’T MATCH!!

FX6-Exposure_1.1.1-600x338 Which Sony ISO RatingS Are Correct?
The FX6 at 320 ISO, 1/50th shutter, S-Cinetone.

 

FX3-Exposure_1.2.1-600x338 Which Sony ISO RatingS Are Correct?
The FX3 with the same 320 ISO, 1/50th shutter and S-Cinetone. It’s clearly brighter.



The FX3 and the A7SIIII are just over 1 stop brighter than the FX6 and FX9 when all the exposure settings are matched. I tested all the cameras with the same lens to ensure this wasn’t a lens issue, but it isn’t the lens.

FX3-S-Cinetone-scopes-copy-1 Which Sony ISO RatingS Are Correct?
FX3 S-Cinetone is brighter compared to the FX6/FX9 and over exposed according to my light meter by just over 1 stop. The white of the white card should be at approx 83% and my skin tones are well into the highlight roll off and looking flat as a result.

 

FX6-s-cinetone-scopes-copy Which Sony ISO RatingS Are Correct?
The FX6’s exposure much more closely matches my light meter and is only a fraction of a stop under with the white card just touching the 83% exposure I would normally expect with S-Cinetone.

 

 

Screenshot-2021-02-26-at-13.16.16 Which Sony ISO RatingS Are Correct?
Here’s the FX3 again, the whites are much, much too bright when exposed against my light meter, even the middle grey is over 60%. The MM+0.7 indication means the camera thinks it is over exposed.

 

Screenshot-2021-02-26-at-13.16.49-copy Which Sony ISO RatingS Are Correct?
And the FX6 with exactly the same settings and the same lens matches my light meter very closely, white is around 83% and middle grey around 45%, as I would expect. Something odd is going on here, it’s not just my light meter it’s something else as the cameras should at least match, even if they don’t agree with the light meter.



I then went on to test other gamma/picture profile settings and I found a just over 1 stop difference between the FX3 and my FX6/FX9 in any similar combination EXCEPT S-LOG3!

Screenshot-2021-02-26-at-13.14.18 Which Sony ISO RatingS Are Correct?
The FX3 shooting S-Log3 now it matches my light meter very closely and the exposure is add I would expect.

 

Screenshot-2021-02-26-at-13.14.41 Which Sony ISO RatingS Are Correct?
This is the FX6 set exactly the same as the FX3 shooting S-Log3. Now they both match and now the both provide the same exposure and closely match my light meter.



When using Picture Profile 2 on the FX3 which is uses Sony’s “Still” gamma and then using the “Still” Profile on the FX6 there is a difference of around 1 stop. If I set the FX3 to PP3 (ITU-709) and the FX6 to ITU-709 then the difference is again around 1 stop, in every case the FX3 is brighter except when you select S-Log3 where the FX3 and the FX6/FX9 match almost perfectly!

I find this very strange. They should not be different. My light meter suggests to me that the FX6/FX9 are correct.

Comparing to my light meter I believe the FX6/FX9 ratings to be correct and the FX3 to be between 1 and 1.3 stops brighter than it should be when using gammas that are not S-Log3. What I really don’t understand is why the FX3/A7SIII match the FX6/FX9 when using S-Log3 but do not match when using the other profiles, normally I would expect to see a consistent offset. This further makes leads me to be sure this is not a problem with my light meter, but something else.

I would love to hear from anyone else that’s able to take a look at the ISO ratings of the A7SIII and compare it with an FX6 or FX9.

The bottom line is – DON’T EXPECT TO PUT THE SAME EXPOSURE SETTINGS INTO BOTH AN FX3 AND AN FX6/FX9 AND GET THE SAME RESULTS, because you won’t, unless you are using S-Log3, then they match. 

Also in the clip metadata I found that 0dB for S-Cinetone is 100 ISO, and whether this is a coincidence or not, if I set the FX3 to 100 ISO and the FX6 to 320 ISO and then match shutter speed and aperture then the exposures are very close.

This one has left me confused!!!!

Don’t Panic! The A7S III didn’t just make your big pro camera obsolete.

Screenshot-2020-07-31-at-10.07.40 Don't Panic! The A7S III didn't just make your big pro camera obsolete.
Sony’s new A7S III video centric mirrorless camera.

So Sony have just launched the A7S III. And very impressive it is. Amazing low light performance, great dynamic range and lots of nice 10 bit codecs. You can even get a 16 bit raw output if you want. I can’t wait to get one. But I really don’t see the A7S III as a threat to or replacement of my FX9 or any other 4K professional video camera.

All the same discussions took place when the original A7S was launched. Sony F5 owners looked at the A7S and said – heck how can that little camera shoot full frame 4K while my camera can’t even shoot s35 4K. Why can the A7S have AF when my F3/F5 doesn’t. How can a camera that produces such beautiful images only cost 1/5th of what my F5 costs. But here we are 6 years on and the A7S and A7S II didn’t replace any of the bigger cameras and when the FS5 was launched people snapped up the FS5, often to replace an A7.

Why? Ergonomics.
 
I don’t ever want to go back to having to carry and use a big box of different ND filters for different light levels. I find the small LCD screen on the back of a DSLR to be of very limited use and while the A7S III does have a very good EVF it’s placement makes it hard to use it on a tripod or in anything other than a simple hand hold with the camera up against your face.
If you want to shoot log then you really want built in LUTs. There are the battery and power questions. How do you power the camera and accessories without needing two or more power systems or a rig to take a big external battery and a bunch of adapters? Then there’s having buttons and switches for all the frequently accessed functions. I could go on but you only have to look at the many franken-rigs that end up built around DSLR type cameras just to make them usable to see the problems. Almost always the first purchase to go with a DSLR is a cage. Why do you need a cage? Because you know your going to have to bolt a ton of stuff to that once small, portable camera to turn it into a professional video making tool.

 

Sure, I will almost certainly get an A7S III and it will be a great camera to compliment my FX9. And yes, there may even be some projects where I only take the A7S III, just as there have been shoots where I have used just my A7S. But it won’t ever replace my FX9, they are two very different tools, each with its own strengths and weaknesses.

 

The image quality gap between traditional large professional video cameras and handheld stills type cameras will continue to get smaller and smaller as electronics continue to be further miniaturised, that is inevitable, but the cameras form factor will still be important.
 
The small cars of today often have all the same bells and whistles as a large luxury car of 10 years ago. Let’s say you’ve gone on vacation (remember those?) and it’s a road trip. You get to the car rental office and you have a choice between a large, spacious, stable, less stressed car or a small car that has to work a bit harder to get you to the same place. Both will get you there, but which do you choose? There might be some instances where the small car is preferrable, perhaps you will be in a lot of narrow city streets a lot. But for most road trips I suspect most people will opt for the big comfy cruiser most of the time.

For me the A7S III will be that nippy little car, a camera that I can pop in a pocket to grab beautiful images where I can’t use a bigger camera. But for my main workhorse I don’t want fiddly, I don’t want a ton of accessories hanging off it just to make it workable. I want the luxury cruiser that will just take it all in it’s stride and get on with the job and right now that’s my FX9.

Why Does S-Log Recorded Internally Look Different To S-Log Recorded On An External Recorder?

I have written about this many times before, but I’ll try to be a bit more concise here. So – You have recorded S-Log2 or S-Log3 on your Sony camera and at the same time recorded on an external ProRes Recorder such as an Atomos, Blackmagic or other ProRes recorder. But the pictures look different and they don’t grade in the same way. It’s a common problem. Often the external recording will look more contrasty and when you add a LUT the blacks and shadow areas come out very differently. Video signals can be recorded using a several different data ranges. S-Log2 and S-Log3 signals are always Data Range.  When you record in the camera the cameras adds information to the recording called metadata that tells your editing or grading software that the material is Data Range. This way the edit and grading software knows how to correctly handle the footage and how to apply any LUT’s. However when you record to an external recorder the external recorder doesn’t have this extra metadata. So the recorder will record the Data Range signal that comes from the camera but it doesn’t add the metadata. The ProRes codec is normally used for Legal Range video and by default, unless there is metadata that says otherwise, edit and grading software will assume any ProRes recordings to be Legal Range. So what happens is that your edit software takes the file, assumes it’s Legal Range and handles it as a Legal Range file when in fact the data in the file is Data Range. This results in the recording levels being transposed into incorrect levels for processing. So when you add a LUT it will look wrong, perhaps with very dark shadows or very bright over exposed looking highlights. It can also limit how much you can grade the footage. What Can We Do About It? Premiere CC. You don’t need to do anything in Premiere for the internal .mp4 or MXF recordings. They are handled correctly but Premiere isn’t handling the 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.
Screenshot-2019-03-01-at-11.04.04 Why Does S-Log Recorded Internally Look Different To S-Log Recorded On An External Recorder?
Using the legacy “fast color corrector” filter to transform the external recording to the correct range within Premiere.
Now when you apply a LUT the picture and the levels are more or less what you would expect and almost identical to the internal recordings. I say almost because there is a slight hue shift. I don’t know where the hue shift comes from. In Resolve the internal and external recordings look pretty much identical and there is no hue shift. In Premiere they are not quite the same. The hue is slightly different and I don’t know why. My recommendation – use Resolve, it’s so much better for anything that needs any form of grading or color correction. DaVinci Resolve: It’s very easy to tell Resolve to treat the clips as Data Range recordings. In the media bin, right click on the clip and under “clip attributes” change 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.

Sony’s XLR-K3M Includes an MI Shoe relocation cable!

Screenshot-2019-11-29-at-17.19.55 Sony's XLR-K3M Includes an MI Shoe relocation cable!
Sony’s XLR-K3M kit includes an MI Shoe relocation cable.

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).

The “E” in “E-Mount” stands for Eighteen.

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:

MOUNT FLANGE BACK SPARE/Difference
e-mount 18mm
Sony FZ (F3/F5/F55) 19mm 1mm
Canon EF 44mm 26mm
Nikon F Mount 46.5mm 28.5mm
PL 52mm 34mm
Arri LPL 44mm 26mm
Sony A, Minolta 44.5mm 26.5mm
M42 45.46mm 27.46mm

Sony’s Internal Recording Levels Are Correct.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

CONCLUSIONS:

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

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

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

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

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

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

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

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

Atomos Ninja V, the arctic and the Northern Lights.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Do the images from my Sony camera have to look the way they do?

— And why do Sony cameras look the way they do?

It all about the color science.

“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.