ProRes 422 Color/Gamma Shift on Export – Same as Source

[Kenn Bell]

So I just outputted to ProRes and Animation Codec. They both look dark and colder. I brought both in to FCP7 for an A/B Test and ProRes still looks dark but Animation looks good, no shift in it while in FCP7.

[Nick Dietrich]

Just in case this helps –

https://www.videocopilot.net/blog/2008/06/fix-quicktime-gamma-shift/

“SOLUTION: After rendering into a QuickTime/h.264 file, open it up in QuickTime and select “Show Movie Properties.” Highlight the video track then click on the “Visual Settings” tab. Towards the bottom left you should see “Transparency” with a drop-down box next to it. Select “Blend” from the menu then move the “Transparency Level” slider to 100%. Choose “Straight Alpha” from the same drop-down and close the properties window and finally “Save.” ”

Just make sure you highlight the video track under show movie properties in order to see the “visual settings” tab. It should work.

[Alessio Santoni]

Hi, after many attempts, a lot of research online and the last test, I solved the problem.
The only way to export a normal or Apple Pro Res 422 HQ version, is to export the project using Compressor. You will get the same quality of color, the same depth and the same contrast of the project.
In this case you can scream (quietly): BINGO!
Best cuts, Rafano

[Tristan Summers]

My two cents, based on what I do for after effects.

If you are rendering for intermediate use, set gamma correction to none.
It will look right in After effects, it is right, BUT it is wrong in Quicktime, with or without the FinalCut Compatibility check box.
If you want to make Pro Res for viewing purposes only, set gamma correction to automatic. Quicktime will now display it properly, however the file itself will be wrong.

If only you could manually set gamma tags in all quicktime files.
If only Quicktime would stop trying to “help” and just display the file exactly as is.

In a year or so it will hopefully have died the death it deserves anyway.
Unless someone else can come up with a movie container that lets you set all the metadata properly.

[Sebastian Leitner]

hey there! just a quick remark. it’s not really a bug, it comes down to some simple things:

if you convert h264 to PRORES you are also converting a) color space and b) bitdepth. let me clarify: a DSLR usually records h264 in 8bits (4:2:0) and rec709 color space whereas PRORES is a sRGB (full range colorspace) format with 10bits (4:2:2 color sub sampling). the difference is basically gamma, meaning you introduce a gamma shift of approx. 0.2 when converting from one format to the other. depending on the direction it gets brighter or darker.

this also applies when converting PRORES (or any other sRGB 10bit format) to let’s say BluRay h264 rec709 8bits format.

final cut pro 7 is the only software i know that can distinguish between those details. if you open it up in final cut pro X it won’t show. there h264 and PRORES mostly looks the same. it might even be off (too dark often) because values are converted to fit the standards.

the problem is further problematic when generating a DCP for the cinema. you need to know what exactly was the color space of the source clip and which it was graded in. DCP is 12bits XYZ color space (so yet another conversion in dynamic range – which will be visable in gamma – color and luma wise). but that’s another story.

so bottom line: always try to level everything to sRGB 10bit if you can. or intriduce the right adjustment layer (0.2 gamma value change – basically midtones – plus or minus depending on oyur conversion direction)

[Tristan Summers]

I too once shared your sweet naive belief that quicktime displayed files properly. but in fact it displays nothing properly. pro res files on a pc look so washed out but they are fine on a mac. yet everyone is happy to use it.

The above is entirely incorrect however. IF you use x264 and set a correct 2.2 gamma tag, the h264 file will look exactly the same, which is why it is used by vimep, youtube, , in quicktime, everywhere. well, not in the FCP7 viewer that is still thinking all content is 2.2 and all macs are 1.8.

the big problem is Apple do not let you set the gamma tag correctly, and quicktime performs incorrect conversions based on filetype interpretations.