bit rate question

J

jeffmellinger

Member
As I've read to do, when I use Compressor to make the mpeg-2, I set avg. bit rate to 6.6 and max to 7.8 for a 17 minute piece. My dvd player can tell me what the current bit rate is while I'm watching. I have some nighttime scenes, that, even when using 1-pass instead of 2-pass, compressor 2 instead of 1.5, etc....still have very muddy blacks and some blockiness to them. You can even see the 2.35 matte I added to the 1.85! it becomes grey and totally noticeable in the night shots! SO anyways, the bitrate never gets above 5 and sometimes dips as low as 2.5 in the night scenes! Yet in the lighter/daytime scenes, it's where it should be. Now, I can imagine that COmpressor sees less info, so determines that it doesn't need to do as much with the night scenes. But it's totally ruining them. How can I get it to look proper? Is there some way to make sure it keeps the blacks sharp and doesn't ignore the nighttime scenes?
Thanks
Jeff
 
Try CBR 8000kb/s. There's no need for using VBR if your clip is only 17min.
VBR (and 2-pass) is good when you want to fit more than 60min to one DVD...this is certainly not your case because you want to use always max. allowable bitrate for MPEG2.
 
2-pass VBR will give you better image quality no matter how long or short your video is.

I'd go back into FCP and do a check of your luma and chroma levels with the scopes, make sure you're broadcast legal. That can cause the problems you describe.

And I'll quote from the book, the best quality you can get, and since you're only doing a 17 minute clip:
Encoding Mode, Two Pass VBR Best
Avg Bit Rate, 7 Mbps
Max Bit Rate, 8 Mbps
Motion Estimation, Best
Frame Controls, Automatic

But you still need footage that has been graded properly to be Broadcast Safe first.

The book I'm quoting is a brand spanking new book out that's killer, simple, easy, and only 20 some odd dollars. "Apple Pro Training Series, Compressor Quick-Reference Guide." I consider it a Must Have for all Mac based video editors.
 
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