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General problems in progressive DV editing
Hi, I have been getting very poor result with slow motion in Premiere Pro CS3. I do not recall having the same problem editing interlaced projects.
My clips are 30P DV filmed with XH-A1 and DVX100A. I put them in a DV project without field. When I put a clip on 50% slow motion, the resolution degraded and the horizontal lines flickered like crazy once rendered. The interesting thing was that everything looked crisp and sharp when the clip was played in the timeline without rendering. Is this normal or there something I can do to improve the result?
There were a few interesting observations I made while trying different settings to correct the problems. Sorry for repeating if these are well known already.
– the resolution degradation and flickering got worse the lower the slow motion setting. ie, at 95% slow motion, the degradation and flickering were minimal.– frame blending does not do much in achieving smooth slow motion. In fact, the degradation and flickering problem disappeared if frame blending was disabled. So, frame blending not for progressive footages??
– Many premiere built-in effects, such as blur, caused the same degradation and flickering problems. They can be solved by putting a “levels” effect before the blur effect. This also solve the same problem I have with Sapphire plugins.
– I tried the Twixtor plugin, which produced great slow motions. However, it has the same degradation problem. I sent my project file and footage to RE:Vision and they observed the same problem. They believe it was Premiere’s problem not able to process the field correctly. The observed the same problem in AE as well.
– There are some problems with the field as well when using Magic Bullet Looks plugin. However, not as severe as twixtor.
All the above were observed in progressive projects (DV, HDV and desktop (uncompressed)) with progressive DV footages. Premiere might be simply poor in editing progressive footages or there are some stupid mistakes I made (hopefully, somebody can help point them out).
Thanks.
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2 Replies
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hey Paul,
I ever have the same problem, but I have another way to get better result of progressive rendering, usually i tried to export .avi progressive, uncompress,it is good. then just in case if you like to export it to DVD or m2v files, better render it on after effect,it has better quality even u have only 1 pass.
I think the rendering process of CS3 is not really good, i got problem by trying to export .m2v files using 2-pass progressive, but the result just interlaced. and if you use CS3 without any render-card. the best slow-mo percentage is around 60% lower could be a problem.
does it helps?
Joe
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The problem is that Premiere assumes any clip with DV compression to be interlaced — and (as it lacks an override via Interpret Footage, etc.) cannot be told that the clip is, in fact, progressive.
Most of the time this does not make a difference. Speed changes, however, is an instance where it will affect the quality.
Like the original poster discovered, there are certain filters that also cause this “auto-deinterlacing” of progressive footage. These are filters built off of the AE model — where fields must be separated in order to achieve interlaced rendering. Premiere assumes your clip is interlaced and separates the fields. Then, since the project is progressive, it applies the effect to and returns only the first field.
I compiled a list of filters that are problematic in this regard:
https://invertedhorn.axspace.com/premiere_cs3_filter_problems.htmlPlacing a non-problematic filter above one of the problem filters seems to remedy this issue in most cases (but not all). In particular, time-based effects (like Time Warp. Posterize Time, etc.) are apparently always applied first and as such are beyond redemption.
Curiously, one cannot use the 3rd party FieldsKit deinterlacer in progressive projects within Premiere for this reason. It would be nice to import a 60i clip into a 30p timeline — and use FieldsKit to make it progressive. But this cannot be done: by the time FieldsKit processes the frame it has already been destroyed by Premiere’s internal deinterlacing.
Apparently Adobe’s apps append a RIFF header marking whether a clip is interlaced or progressive. Premiere supposedly honors this flag when processing footage. So, a possible workaround would be:
1.) import your 30p DV clips into After Effects
2.) make sure you turned off separate fields on “Interpret Footage” options for all clips
3.) re-output your clips from AE (no field rendering) as DVPremiere should now see these correctly as progressive. It’s a nightmare, I know. The absence of a field order/progressive frame option in Premiere’s Interpret Footage dialog is a major oversight on Adobe’s part.
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