2007 August 28th, 16:06
HV20 24P Reverse Telecine in Compressor - Chroma Lags behing Luma!
Hi all. I've shot scenes with a 35mm adapter and an HV20 in 24P mode (which records 24P in a 60i stream in HDV). Then I've imported into FCP6, rotated the image 180degrees (to get it upright) and then used the new Compressor to Reverse Telecine the footage to get it into 24P in Apple Prores 422 1080P. Looks great, except...
The Chroma lags behind the luma! Two frames it's correct (and on the luma) then the next two frames it lags behind the luma, then repeats. It's noticable when there's big movement with contrasting colours in the image (red really stands out).
Did I miss a step? Also note, the Chroma that is lagging is heavily interlaced, even though the Luma has been turned into proper progressive!
2007 August 28th, 18:48
I saw a similar thing in Premiere Elements 3.0 on a clip with a lot of motion. I put the same clip in After Effects CS3 and didn't see the issue. I'm thinking maybe the NLE is just having a problem presenting the HDV MPEG-2 properly.
2007 August 29th, 00:29
I found the problem - I was applying a 4:2:0 > 4:2:2 filter at the same time as rotating the image AND exporting to Prores 422..
Solution: Don't use the filter at the same time as exporting. Solved.. thanks Frank.