Avid users

Sean McHenry · January 6th, 2006, 12:10 AM

We discovered an issue some folks may not realize the other day. We brought in footage from our JVC HD-100 cameras and were working in the HDNX75 codec. The gentleman doing the edit had converted to an SD project at some point to have a client monitor output. He laid on several color corrections and other effects in SD.

The project was bumped back to HDNX75 at some point and all the video with those SD based effects looked awful. The software was basically saying the renders in SD were valid renders but they don't convert well when being bumped back up. Footage with these SD effects was looking like badly interlaced or inverse interlaced footage. The solution was to force a re-render of all the effects in the HD based timeline. The alternate, when that didn't work was to dump the SD effects and recreate them in HD. From there out everything was OK.

The moral of the story is do your effect work in the highest level video possible. You apparently cannot bump SD effects to HD very easily.

Perhaps a fix for future Avid Xpress Pro HD versions would be to dump the renders (precomputes) when moving up into higher deffinition automatically rather than hanging on to them.

FYI stuff

Sean McHenry

Richard Alvarez · January 6th, 2006, 08:14 AM

Well, I guess that makes sense in terms of workflow. No different than having to re-render a low rez effect (Say, at 15:1) when uprezzing to 1:1. Still, it's good to keep in mind.

Sean McHenry · January 8th, 2006, 03:38 PM

Some of them wouldn't work even after re-rendering. We actually had to kill a few effects and recreate them in the HD resolutions. That took a while.

YMMV.

Sean

January 6th, 2006, 12:10 AM	#1
Sean McHenry Trustee Join Date: Mar 2004 Location: Hilliard, Ohio Posts: 1,193	Avid users - a note for HDV work We discovered an issue some folks may not realize the other day. We brought in footage from our JVC HD-100 cameras and were working in the HDNX75 codec. The gentleman doing the edit had converted to an SD project at some point to have a client monitor output. He laid on several color corrections and other effects in SD. The project was bumped back to HDNX75 at some point and all the video with those SD based effects looked awful. The software was basically saying the renders in SD were valid renders but they don't convert well when being bumped back up. Footage with these SD effects was looking like badly interlaced or inverse interlaced footage. The solution was to force a re-render of all the effects in the HD based timeline. The alternate, when that didn't work was to dump the SD effects and recreate them in HD. From there out everything was OK. The moral of the story is do your effect work in the highest level video possible. You apparently cannot bump SD effects to HD very easily. Perhaps a fix for future Avid Xpress Pro HD versions would be to dump the renders (precomputes) when moving up into higher deffinition automatically rather than hanging on to them. FYI stuff Sean McHenry __________________ ‘I don’t know what I’m doing, and I’m shooting on D.V.’ - my hero - David Lynch http://www.DeepBlueEdit.com

January 8th, 2006, 03:38 PM	#3
Sean McHenry Trustee Join Date: Mar 2004 Location: Hilliard, Ohio Posts: 1,193	Some of them wouldn't work even after re-rendering. We actually had to kill a few effects and recreate them in the HD resolutions. That took a while. YMMV. Sean __________________ ‘I don’t know what I’m doing, and I’m shooting on D.V.’ - my hero - David Lynch http://www.DeepBlueEdit.com

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January 6th, 2006, 08:14 AM	#2
Richard Alvarez Inner Circle Join Date: Sep 2002 Location: San Mateo, CA Posts: 3,840	Well, I guess that makes sense in terms of workflow. No different than having to re-render a low rez effect (Say, at 15:1) when uprezzing to 1:1. Still, it's good to keep in mind.