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Compressor issues with old Beta-cam footage

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Andy Edwards
Compressor issues with old Beta-cam footage
on Apr 24, 2007 at 12:47:55 am

I've been working on a long form Doc for the past couple of years. The footage was shot years ago in Beta-Cam. We mastered everything to Digi_beta and I have been working with the Final Cut Footage to make the DVD.

I am getting some major artifacts around the edges of the horses when making the DVD. I think the black lines are a part of the old Beta-cam footage that could not register the high whites, thus the blow out and black registration....could be wrong, but not sure.

Does any one have any ideas I can try to smooth this out in the compression to DVD? I have uploaded some pics to a web page that you can look at.
http://www.aedigitaltv.com/horses.html

I've been using Compressor version 2.3: Tried both CBR, and VBR variations, both exagerate the black line. Lower Field selected out of FCP, so no strobbing in Compressor.

Appreciate any help as I am stumped. I have locked everything down to be within broadcast safe, but the MPEG-2 compression seems to enhance the black line .

Andy Edwards


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Rich Rubasch
Re: Compressor issues with old Beta-cam footage
on Apr 26, 2007 at 1:23:59 am

I would look at a color correct....I would do it in After Effects and matte out the horses and try to get their whites down a bit. Kind of looks like a luma issue...not sure exactly why compressor is fattening up the black line.

Rich Rubasch
Tilt Media


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Andy Edwards
Re: Compressor issues with old Beta-cam footage
on Apr 26, 2007 at 4:01:22 am

Rich, thanks for chiming in. Well I think we are SOL. I went back to the original footage from the first online session and the black lines are in the footage, but not as pronounced as it comes out after the compression.

As this has been a long term project....editing off and on for over 5 years and the original Betacam shoot was in the mid 80's..... it is a shame to have this crop up in the final stages. There is no more budget to to re-online/cut mattes/color correction for the DVD. The sad part is the online was all tweaked to be within broadcast spec with waveforms etc. It is only with the MPEG-2 compression that the black lines raises its ugly head.

Oh well, couple more things to try and then see what the client wants to do.

Thanks
Andy


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Tom Brooks
Re: Compressor issues with old Beta-cam footage
on Apr 29, 2007 at 11:40:13 pm

Andy, I'm not sure what you mean by "Lower Field selected out of FCP, so no strobing in Compressor." I have a couple of hunches, but I'd like to understand this before making a suggestion. Do you know if that footage was shot with a tube camera as opposed to a CCD camera? It looks vaguely familiar from the tube days. Thx.
-Tom


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Andy Edwards
Re: Compressor issues with old Beta-cam footage
on Apr 30, 2007 at 1:02:25 am

Well not sure if it was a tube or not. Serial Betacam #8 camera and the footage was from around 1983 or 84. So probably tube? I was talking to another editor and he stated that it might be part of the old betacam artifacting prior to CCD cameras. I'm open to any hunches Tom, so ask away :-)

What I meant about the lower field, was you can get strobbing when you encode the MPEG-2 to the wrong field out of FCP.

Thanks.
Andy


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Tom Brooks
Re: Compressor issues with old Beta-cam footage
on Apr 30, 2007 at 2:27:08 am

Andy,
Based on your info I got nuttin much to offer. It looks like the sensor in the camera is saturating on the overexposed white and then overshoots on the adjacent darker tone.

Is there any deinterlacing applied to this footage?

The fact that the problem is worse in MPEG makes me suspect something wrong with the fields. On a long shot, you might try converting a short section to progressive before encoding to MPEG and see if it makes any difference. Export self-contained Quicktime Movie as PhotoJPEG (or Motion JPEG-A?) at 100%, progressive, frame controls set to Better, and then try the MPEG-2 encode from that. Of course, this will change the motion characteristics of your video, which might not be acceptable. -Tom


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Tom Brooks
Re: Compressor issues with old Beta-cam footage
on Apr 30, 2007 at 2:28:38 am

Andy,
Based on your info I got nuttin much to offer. It looks like the sensor in the camera is saturating on the overexposed white and then overshoots on the adjacent darker tone.

Is there any deinterlacing applied to this footage?

The fact that the problem is worse in MPEG makes me suspect something wrong with the fields. On a long shot, you might try converting a short section to progressive before encoding to MPEG and see if it makes any difference. Export self-contained Quicktime Movie as PhotoJPEG (or Motion JPEG-A?) at 100%, progressive, frame controls set to Better, and then try the MPEG-2 encode from that. Of course, this will change the motion characteristics of your video, which might not be acceptable. -Tom


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Tom Brooks
Re: Compressor issues with old Beta-cam footage
on Apr 30, 2007 at 2:30:00 am

Andy,
Based on your info I got nuttin much to offer. It looks like the sensor in the camera is saturating on the overexposed white and then overshoots on the adjacent darker tone.

Is there any deinterlacing applied to this footage?

The fact that the problem is worse in MPEG makes me suspect something wrong with the fields. On a long shot, you might try converting a short section to progressive before encoding to MPEG and see if it makes any difference. Export self-contained Quicktime Movie as PhotoJPEG (or Motion JPEG-A?) at 100%, progressive, frame controls set to Better, and then try the MPEG-2 encode from that. Of course, this will change the motion characteristics of your video, which might not be acceptable. -Tom


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Andy Edwards
Re: Compressor issues with old Beta-cam footage
on Apr 30, 2007 at 11:35:14 pm

[Tom Brooks] "Export self-contained Quicktime Movie as PhotoJPEG (or Motion JPEG-A?) at 100%, progressive, frame controls set to Better, and then try the MPEG-2 encode from that"

Thanks for the ideas tom. I have been playing around with the footage and trying your recipe. where is the progressive option? in a Sub-menu export of FCP? Can't seem to choose it.

I'm trying a few flavors of Motion JPEG and Photo JPEG and getting ready to compress them in Compressor. Not able to see that much of a difference in the self contained QT's.

[Tom Brooks] "Is there any deinterlacing applied to this footage?"

Not to my knowledge. The footage sits in a 8 bit-uncompressed interlaced sequence with lower field checked.

Will chime back in after all the test renders and play back on DVD.
Andy


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