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Blackmagic vs Photo-Jpeg vs Animation
hello!
when working in after effects and rendering in blackmagic 8 bit, we noticed a slight change in luma and chroma, so i started to test some codecs and came along some strange items.
all tests i did on a g5 dual 2.5, blackmagic video-card and using quicktimes.
first thing i did was a generation test. in after effcts i rendered out a short test sequence,
reimported it, rendered through again. this i did ten times. then i compared the original clip with the tenth generation-clip in different codecs by applying an extreme difference key.blackmagic 8bit: a massive loss of luma and chroma in the tenth generation was clearly visible.
photo-jpg (100%): difference between first and tenth generation was only visible by applying an
extreme difference key. overall look was very good.
animation: absolutely no difference between first and tenth generation.then i did the same thing using final cut pro. i captured a test sequence, played it out to digibeta, recaptured … again ten times. everytime i changed the codec i also changed capture and timeline settings.
blackmagic 8bit: nearly no loss in the tenth generation.
photo-jpeg (100%): little loss, but still ok.
animation: capturing in animation codec always resulted in a software crash after capture. no video output,
when trying to play out.i do not understand, why there is such a big loss in blackmagic 8bit when rendered in after effects, but nearly no loss, when i do the same thing by playing out and recapturing with fcp and no after effects involved.
somehow after effects seems to handle the codec in a different way, which does not seem to make sense to me.could someone please share his knowledge with me?
another issue are the file sizes: blackmagic 8bit quicktimes do always have the same size depending on teir lenght.
photo-jpg (100%) file size depends on the image-detail. overall they are about 40% – 60% of the file size of blackmagic 8bit files.
animation file size also depends on image detail. overall they are about 30% – 150% of the file size of blackmagic 8bit files.what we are looking for is a codec we can use during the whole production process (capturing in fcp, compositing in after effects, rendering, playing out with fcp). there should be as little loss as possible and files should not be too big.
photo-jpg seems be a good choice to me.
what codecs do you use when working with a blackmagic video-card and after effects and what are the pros and cons?
thanxs a lot, zealander.
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5 Replies
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foto jpeg works with 100% in rgb 4:4:4. that is fine for works in after effects (render also internaly in rgb). in fcp is this not fine. use foto jpeg with 75% (works in yuv 4:2:2 with highest quality).
animation is also a rgb codec. fine for after effects. better as foto jpeg, works lossless.8bit blackmagic is fin in fcp, better for digibeta is 10bit. yuv-codec in after effects is not fine, permanently change colorspace with calculation error…
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Very interesting. Would this also apply to Apple Lossless 8-bit as well as BM?
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“Would this also apply to Apple Lossless 8-bit as well as BM?”
the same.
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the basic underlying problem ist the colorspace conversion. rgb any uv aren
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So, since AE works only in RGB, what’s the solution to rendering out video (as opposed to graphics) in AE?
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