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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Varying Black Levels

C

craigjkharris

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When I perform a primary color pass in RocketCineX, my blacks look great and read properly in the histogram.

HOWEVER...

The transcoded files (ProRes) show completely different black levels. In my case, they are always brighter (like 2 stops).

Can anyone suggest why or what the fix is?

Craig
 
Gamma Correction Tests

Gamma Correction Tests

CJ Roy said:
I don't have it in front of me right now, so I'm going off of memory, but in your export settings there's a checkbox with "Gamma Correction" or something like that. The default is set to auto, but I usually switch it to none.

Maybe that's it?
Click to expand...

Thanks CJ,
I've exported two Pro Res files with the Gamma Correction turned ON and OFF. I've attached two pictures showing the results. Please note that the second image (with no gamma correction) is darker than the auto gamma picture, but neither are close to the image generated in RocketCine.

1. Automatic Gamma Correction (Pro Res 444 - 2K)

autogamma.jpg


2. No Gamma Correction (Pro Res 444 - 2K)

nogamma.jpg
 
I believe this is a QuickTime Gamma issue. We are all plagued by this. Looks great in the Red tools but looks washed out in QT.

Are you on Snow Leopard? I've heard that this corrects (or at least drastically improves) the situation, but it would be good to know for sure.
 
My results were the opposite, looked perfect in RocketCine-X but way too dark in ProRes4444. It's totally unpredictable what's going to come out on the other end.
RCX doesn't really have a whole lot of export settings, so what gives?
 
Milan,

I still say it's a QuickTime issue, not Red. Can someone chime in?
 
jimhare said:
Milan,

I still say it's a QuickTime issue, not Red. Can someone chime in?
Click to expand...

We don't have a clear answer yet from Apple on how to resolve the gamma issue and Quicktime Auto correcting for 1.8 vs 2.2.

In SL, Prores does work better in some apps but not h.264.
 
Isn't this problem happening not only because of the gamma issue but the black/white point issue? Proxy/FCP/Color seem to work fine but when I transcode using the RELINE, it seems only output 0 to 1023, then when you import that to FCP, it automatically adjust it to display at 64 to 940, then when you send that to Color, it displays in 0 to 1023.
 
Craig,

For what it's worth, the shot looks great.
 
Any Solution to this yet? I just ran into the same thing.
 
It seems like his is the same problem one encounters when briningin in rgb material into FCP. I know that ProRes is a YUV codec, is it possible that going from RGB space to YUV space something is being missed? On a side note I wish there was a better description of the gamma space and color space controls.
 
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