DV media to DigiBeta Master using BlackMagic Extreme

[Chris Borjis]

I’ve been doing both and so far it is not an issue.

There is no tearing when going from digibeta (486)
to mpeg2 for DVD (480) which is a relief.

I think its cropping the 6 lines which are in overscan territory anyways.

[Kristian Lam]

Hi,

Not to worry. We don’t do any scaling and account for the different. You will not get an interlacing issues.

regards

Kristian Lam
Blackmagic Design

[Adam Levine]

One note: if there is a significant amount of rendering (anything more than a few transitions), you should make sure you output from an uncompressed 8-bit timeline. This can be achieved via Media Manager with recompress option, recapturing with an SDI deck, or the quickest, just drop your DV seq into an uncompressed seq. Make sure you offset it by 1 pixel in the Y axis to get your fields on sync (unless you pulled up your footage to progressive frames only and cut at 23.976, in which case it doesn’t matter).

[Ellaella]

I really appreciate everyone’s replies.
Adam, I’ve heard of the process you suggested in the past and have been wondering technically how resizing and adjusting that way is preferable to just letting the card do it (I believe you, just want to understand better). What is the difference between what the card does and what dropping the DV media into an uncompressed 8-bit sequence does? Or what does the card not do that this process makes up for? We do have many transitions and effects so I want to do this the right way.
Thanks again!
Ella

[Adam Levine]

Twofold issue, both having to do with having significant rendering in the timeline:

1) If you are rendering a lot of the program, then you don’t want to render in a DV timeline. This will do the DV 5:1 compression on the rendered section, adding all the usual issues that come from rendering to a highly compressed format, which will then be decompressed on the way out the SDI pipe (though the picture quality is not increased in any way by this decompression). You will see the difference most significantly in graphics, color correction and longer dissolves.

2) If you are doing a color correct pass, it is best to media-manage-decompress (or recap via SDI) first, then do the color pass. This way, you will see your color correction in 4:2:2 as well as the correct gamma, which DV does not have.

[Ellaella]

Hey Adam,
If you happen to check back into this thread, I have a question about the 1 pixel y-axis adjustment:
Using the method you suggested, I first put my 720×480 sequence into a 720×486 timeline, but then I need to bump my media up one y-axis pixel to account for the new interlacing pattern. This would mean I’d have to go into each clip and change the motion settings one by one. To avoid that, could I export an FCP movie out of the 720×486 sequence, reimport it, and then bump the whole movie up by 1 y-axis pixel?
Thanks very much,
Ella

[Adam Levine]

[ellaella] “This would mean I’d have to go into each clip and change the motion settings one by one. To avoid that, could I export an FCP movie out of the 720×486 sequence, reimport it, and then bump the whole movie up by 1 y-axis pixel?”

Or just put the entire sequence in and change the motion setting on the sequence