Loss of video quality with the FX1?

[Steve Crisdale]

Originally Posted by Jim Montgomery

Steve
Using Cinemacraft Basic

Mode MPEG-2, 2 pass VBR and elementary stream
Bitrate Min 0 Avg 5 Max 9
Quality set Natural Picture
Aspect Ratio 16:9

MPEG Video Setting
Add sequence mode
Offset line = 1
Intra DC precision = 10
Block scan order alternate

Jim

OK. I've done some DVD test stuff in Vegas5 using CFHD avi's as the source clips.

And while I don't use the CinemaCraft encoder you appear to be using; I certainly wouldn't render any DVD MPEG2 files with the minimum bit-rate set at zero... The potential for overly degraded quality in such a low setting, would be too great... to my mind anyway. I'm also not too sure what the "Offset line = 1" setting refers to? If it's to do with upper/lower fields first, that could also be a factor. HDV is upper field first, so if = 1 indicates this, maybe = 0 indicates progressive, which may prove a better option. Just guessing on that score though.

You may also need to lower the "Intra DC precision" to = 9, or even = 8... as 10bit is a little high for anything other than an editing intermediate, and there's no advantage to 10bit DVD level MPEG2. It may even cause display errors on playback because the bit-depth isn't recognised as a valid DVD level bit-depth.

Anyway, from many experimental clips and renders... the following information was distilled. It may be of some use.

My MainConcept MPEG2 settings for the best results (when viewed on a computer monitor) are:

16:9 Progressive
video Quality: High
2 pass VBR: Max - 9.3Mbit, Av - 6.0Mbit, Min - 1.92Mbit
Video Co-efficient: 9Bit
Program stream

As I have the FX-1e PAL the progressive rate is 25fps. The rendered clips using these settings look amazingly close to the original HDV source clips. Certainly as good - if not better - than 'Hollywood' style commercial DVD quality.

If you are rendering interlaced DVD level clips, you may well be seeing interlacing flicker and other interlacing artifacts that would appear to degrade the quality significantly. And don't use Windows Media Player to view the resulting files either. Use a dedicated DVD player application... like PowerDVD 5, or WinDVD 6 which both have interlace reduction options, and the best muxer/demuxer drivers available at the moment.

[Jeff Baker]

Thanks for the settings info. How do you set the progressive flag in MainConcept? I'm in NTSC land and use the 8mbit constant bitrate settings as long as I am under 60 min for a project. And I now see that I have to choose "upper field firs" in the pop up window under premiere pro, but otherwise I don't know what to do about the 1.33 ratio issue or progressive when trying to convert from hdv to DVD...