That's what I thought and then saw your post above. Just temporarily confused by the fact the sony process for the FX7 is different than the HV20's. Thanks for replying. BTW. Very impressed with the trial download of Neo. Thanks for allowing the trial over the net, I'll bet I'll be purchasing it in two weeks.

More than just Chroma crosstalk? 50% frames are off...
 

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 (Apple Prores 422). 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).

It's not just every 4th frame - it's 2 'bad frames' frames every 2 good frames! About 12 frames every second are off ... i.e. half! 50%!

Did I miss a step, or is it just this bad?

24p from the HV20 is fine, the error always in the pulldown removal. Here is my blog entry on the subject : http://cineform.blogspot.com/2007/07...4p-or-not.html


You might try removing the pulldown before rotating the image, as a bad (frame based) rotate will mess with the field ordering.

I think you're right - remove the pulldown, THEN rotate the image. *sigh* Because I use a 35mm adapter, that'll add a lot more time to my renders.. they'll take twice as long now. But hey, it's the price of a good value camera. Thanks David.

EIDT: Did a test - David's correct - when shooting 24P with the HV20, do not reverse telecine and flip in FCP6/Compressor in one step.. make it two steps (two full renders, unfortunately). Good news: more confident than ever in the HV20's 24P ability.

EDIT: I was off, again.. there was a filter that was messing the colour up - I was applying in the process to fix 4:2:0 to 4:2:2.. so, yes, the footage can be flipped and deinterlaced in one step, however, the G Film plugin has to be done after, in a second step. So it's even better than I thought!

If you have an Intel Mac, you could purchase NEO HD and run it under Boot Camp, it will flip the image, remove the pulldown, bump the image to 4:2:2, and encode to CineForm MOV which will work on a FCP6 timeline, all in one step (real-time during ingest.) :)

I've got the Intel Mac Pro with HD-SDI / HDMI in.. you build that kind of functionality for the Macintosh, natively, and you'll have another buyer ;) Because, all in one step in OS X, that’d be pretty darn cool.

In light of my recent findings, I must say, the original poster was way off. Once properly treated - and it's not hard, the tools are easily at hand - the HV20's 24P footage is truly true 24P, just like we've all been saying all along. The chroma is fine - I messed up my reverse telecine before, but now that it's done without tinkering, it works as it should. Rest easy - the HV20 will take care of the rest.

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for Robert:
 

Hey Robert,
When in FCP, don't "rotate" the image, but rather, use "flip." (or is it "Flop"? I'm not sure off hand.)
Check both the "vertical" and "horizontal" boxes, and it will get your image in the correct orientation without the need for rendering anything.

The image quality will be better, too.

Just a trick I discovered.

joel

Aye Serge, thanks for steering me on the right track with that FPS thing. ;)

Joel, good idea. However, I just spent five minutes scrutinizing the frames that I rotated, and there is no detectable image loss. So the 'flip' filter might be faster, but I can't see how it'll make the image better. Thanks though.