That was sort of what I did for my test. I used color bars, a 16 bit source HD tiff file from Nuke (write node col space set to sRGB). Generated two quicktimes from that tiff file to 10 bit uncompressed, one in After Effects and one in Final Cut. Final cut tiff imported with gamma level set to 2.22 and exported via quicktime movie and not Quicktime conversion. Comparing the tiff and the two quicktimes in after effects give me almost no difference (there is a minor diff if you compare att pixel level and I guess that is due to going from rgb to yuv). Comparing in Final Cut gives the same result as after effects. But if I bring all those files in to Nuke (reads set to sRGB) I will get a chroma shift in both quicktimes compared to the tiff and the original Nike colorbar. It's not a typical gamma shift, I know what that looks like. See for yourself: https://www.dropbox.com/gallery/12933518/1/Quicktime_Test?h=2fe85d So if this isn't an issue with the read node in Nuke and quicktime uncompressed what am I doing wrong in my test? You say there are no specific issues with uncompressed and what would your preferred quicktime workflow for Nuke be then? If I really had to work with quicktime input, something I try to avoid :-)
Cheers, Johan On Mon, May 30, 2011 at 5:32 PM, Adrian Baltowski <[email protected]>wrote: > Hey > > First of all: it's possible to keep a controlled workflow with Quicktime > format, and there aren't any specific issues about 10 bit uncompress codec. > But there are mane other things: > > 1. Which application has generated those files? (Final cut, Avid or > something else), in which format (resolution)? > 2. What is destination? > 3. And very important question: what do you mean: "chroma shifts"? > > Very often I notice that peoples confuse color shifts and gamma shifts; > it's not the same. Of course those terms are ambiguous, so to be clear: > It's possible that picture is gamma shifted ("brighter" or "darker"), while > hues of colours are not shifted, and vice versa. And of course: gamma as > well as colors hues might be shifted. > Some color and gamma shifts are quite predictable but it's better to make > sure. The oldest and the best way to check it out are color bars. Hues of > the bars are standarized: > > 60 deg- Yellow > 180 deg. - Cyan > 120 deg. - Green > 300 deg. - Magenta > 360 deg. - Red > 240 deg. - Blue > > If yours colors keeps proper values between application, which generates > your files and Nuke, you are lucky. But check it first if you can, and then > we will continue. > > > Best > Adrian > > > > > > > > W dniu 2011-05-30 14:27:16 użytkownik Johan Boije <[email protected]> > napisał: > > And this is on OSX, Nuke 6.2v4 > > > > On Sun, May 29, 2011 at 9:46 PM, Johan Boije <[email protected]> wrote: > >> Normally I wouldn't go near quicktime but for reasons I can't control I'd >> like to read Quicktime Uncompressed 10-bit YUV directly in Nuke. This will >> introduce a distinct chroma shift so it's not possible. What's your >> experience with this? Any solutions? >> I Believe I've read numerous threads on this matter but didn't find >> anything specific on 10bit uncompressed. I know it's complicated and that it >> probably has to do with Nuke's "home-brew" of the quicktime reader. Normally >> I wouldn't consider anything but file sequences in Nuke, or in the rest in >> my workflow for that matter. But this time I have like a gazillion quicktime >> files that needs to be treated and I'd prefer not to have to convert them >> elsewhere previous to bringing them to Nuke. >> What's your experience with this? Is it even possible to keep a controlled >> workflow with any type of uncompressed Quicktime format? I've had a look at >> ProRes before and that was problematic too with chroma shifts introduced. >> I hate hate hate hate Quicktime. From the bottom of my heart. Hate it. >> Sorry.... now I feel better. >> >> Cheers, >> J. >> > > > > _______________________________________________ > Nuke-users mailing list > [email protected], http://forums.thefoundry.co.uk/ > http://support.thefoundry.co.uk/cgi-bin/mailman/listinfo/nuke-users >
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