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Exporting Uncompressed 8bit SD getting rejected
My uncompressed quicktimes are being rejected by post houses. When I asked for specific technical reasons all I got was “blacks are too high.” Not the best description and not helpful since the video itself is very black to begin with (actors in black outfits, dark lighting, etc). Then I took it to another post house to get a second opinion and they also agreed that the quicktime wasn’t the best quality.
The original tape that I received was a Betacam SP tape. The tape was digitized 1:1 through SDI from a Sony SX deck into an Avid Media Composer 4. The file was exported from the Avid as an uncompressed 8bit 4:2:2 quicktime (601 color level, native dimension, even field). Here is the list of issues they had with the clip:
1.) The blacks are lifted, giving the video a “milky” appearance.
2.) There is visible interlacing from a previous file conversion which is now permanently part of the file.
3.) Similarly, there is a lot of moiré visible in this video, also permanently part of the file.
4.) There are a lot of compression artifacts visible in the file. The file provided to us was an “Uncompressed Quicktime”, but it is obvious that it was created from a much more compressed version of the file. The general quality of the file is equivalent to a YouTube video. (This gave me a good laugh)
Concerning #2, I’ve made several attempts to make the clip progressive (to remove the interlacing) by using the timewarp effect. Unfortunately, the quicktime definitely looks pixilated when exported. I have also tried to address the black level issue by color correcting it and my engineer has looked at the original clip and said the levels look acceptable. I also placed a color safe limiter effect on the sequence when I exported the clip. Any suggestions would be greatly appreciated. I’m at a loss as to what to do next.
Avid Media Composer 4.0.5.2, Nitris, PowerMac 2×2.8Ghz Quad-Core Xeon, 6GB 800MHz DDR2 FB-DIMM RAM, OSX 10.5.6, 300GB internal HDD, 4TB RAID
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4 Replies
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Concerning issue #1, you can export “601” levels (RGB 16-235) or RGB levels (RGB 0-255) from Avid. It sound like the people getting the Quicktime want the latter, although most software can import either if you set it correctly.
On the other issues, if they indeed took a low-res file and transcoded it to an uncompressed QT file, all the artifacts and interlacing issues will be “baked-in”, and you will not be able to undo them.
Maybe you should get the original file and fix it yourself.
Bill Stephan
Senior Editor/DVD Author
USA Studios
New York City -
I actually created the original file from a Beta SP tape. I digitzed in 1:1 into the Avid and exported an uncompressed 8bit quicktime file.
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I’d be interested in knowing what, if anything, you find is the resolution. A friend of mine is having the same issue, and I really only speak FCP, but even I can see from the screengrab she sent that something’s not right in Whoville. All I know is- it’s an old Avid (PC), exported uncompressed 4-2-2, brought it over to a mac with FCP to do a DVD with menus, etc, and the blacks looked horrible, and apparently there’s some weird ghosting thing going on with the text (generated in Avid). Attached part of the screenshot she sent me, yehaw.
https://f1.creativecow.net/1046/1046 -
I don’t think I’m having the same problem. I definitely agree that something is wrong in whoville with blacks like that.
I’m digitizing 1:1 SDI into Avid from a BetaSP tape. So the quality should be as good as I can get. When I export to an Uncompressed quicktime 8bit, this is what I get:
This is what my blacks look like:
This is the interlacing that occurs:
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