Color correction with multicam

[Adam Gold]

So this is probably a stupid question: we're doing a four-cam multicam edit in Premiere with Aspect. As much as we tried in the theatre, the cams don't really match, color-wise and exposure-wise.

To do a multicam edit in Premiere, you essentially use your "raw" tape as the basis for a multicam sequence; you nest the four stacked original streams into a new sequence. Our original footage for each act of the play is an hour x 4 cams.

So it seems to me that there are two or three ways to color-correct to match the cameras: either render each edited multicam sequence into a single CFHD-AVI and apply color correction and re-render, or color correct each of the four streams at the beginning and use the rendered, color-corrected streams as our original "raw" footage, so each sequence doesn't need to be corrected and re-rendered independently. Or I suppose you could "nest" each edited sequence into a third sequence and color-correct it as a whole (rather than hundreds of individual clips).

I know correcting the edited sequences means fewer frames are affected (as obviously only one in four streams is onscreen at any one time) but it just seems simpler to correct the color prior to editing. I could let each stream re-render while I'm doing other things, like sleeping.

Does any of this make any sense? Recommendations, anyone? I guess I'm also wondering if multiple generations of CFHD-AVI means any loss, although I know in theory it shouldn't.

Thanks,

ag

[Bill Rankin]

Color correction requires (at least for my machine) up to 8 hours (for one hr and 45 minutes of video) to render to AVI for import into Encore. I have dual core AM64, 3 gigs of ram, and XP Pro.

I can't answer your question, other than the comment above, but I would like to add to the discussion "Is there a way to color correct without the excessive render times?

[Stephen Armour]

Originally Posted by Adam Gold

So this is probably a stupid question: we're doing a four-cam multicam edit in Premiere with Aspect. As much as we tried in the theatre, the cams don't really match, color-wise and exposure-wise.

To do a multicam edit in Premiere, you essentially use your "raw" tape as the basis for a multicam sequence; you nest the four stacked original streams into a new sequence. Our original footage for each act of the play is an hour x 4 cams.

So it seems to me that there are two or three ways to color-correct to match the cameras: either render each edited multicam sequence into a single CFHD-AVI and apply color correction and re-render, or color correct each of the four streams at the beginning and use the rendered, color-corrected streams as our original "raw" footage, so each sequence doesn't need to be corrected and re-rendered independently. Or I suppose you could "nest" each edited sequence into a third sequence and color-correct it as a whole (rather than hundreds of individual clips).

I know correcting the edited sequences means fewer frames are affected (as obviously only one in four streams is onscreen at any one time) but it just seems simpler to correct the color prior to editing. I could let each stream re-render while I'm doing other things, like sleeping.

Does any of this make any sense? Recommendations, anyone? I guess I'm also wondering if multiple generations of CFHD-AVI means any loss, although I know in theory it shouldn't.

Thanks,

ag

We color correct the CF'ed input ALWAYS before using it, as much as is possible. It can be a royal pain to do after editing, unless all you do is cuts from one cam to another! We do them all in AE and the fastest "run 'n gun" way is to use a single image from the production, to try to color match the four AVI's more closely. It actually gets you within the ballpark.

Did you use a color chart with each cam before beginning? That's the best way. Though spendy, good color charts are invaluable.

[Adam Gold]

Originally Posted by Stephen Armour

We color correct the CF'ed input ALWAYS before using it, as much as is possible.

After color correcting the originals, do you then render each to a new CFHD-AVI file and then do all your cutting with the new files as your "originals"? I'm trying to avoid re-rendering each edited sequence (at least for the CC part). This is probably laughably amateurish for you guys, but I just drop the Premiere "Auto Color" and "Auto Levels" effects onto the clip and that seems to do a pretty good job of smoothing things out. CF had color-correction tools, but all must be manually tweaked. I assume they work in real-time without re-rendering for playback, but I like the simplicity of the PPro Effects.

My current workaround, until I hear otherwise, is to apply Auto Color and Levels to each of the four source clips but not render that timeline. Rather, I'm rendering each edited timeline for each scene while I'm doing email and forums and other boring stuff on a different computer.