Color Correction Help - Matching Constantly Changing Exposure

Oh my ... so you've been provided some glorious files to edit. Yuck!

First thing you have to do when working with multiple camera shoots is get everything to "neutral". So when you go clip to clip, they look like un-corrected but decently shot clips and you don't really notice camera differences. This ain't to get to pretty, but to get to a decent starting point.

I agree with the thinking that getting the tonality balanced really should be done first. I've found that going to the Creative tab, zeroing Saturation, then going back to the Basic tab to work at tonal things is great, as you can turn that tab's correction on/off to check what your work has done to the original clip. I've got a blog post showing exactly what the basic tab's tonal controls do, some of which may not be what you expect here. And it may help speed you along in your work.

Lumetri Basic Tab: What do the tonal controls really do? – rNeilphotog

The biggest problem with tonal work in the Basic tab is that nothing really works on the bottom end in a linear fashion. "Blacks" is a sort of wag-the-tail effect, mainly working from a couple points above the 'current' black area at first touch up to the 20 value at full force. But it does very little to the values above it, so it does some odd stretching and/or compression to the values from about 50 on down.

It takes working Shadows and Blacks together to accomplish something fairly smooth down there.

Exposure ... is an odd tool. Taking it "up" to positive values is like a curves adjustment lifting from about the 70 point, but doesn't do anything on black point and can if pushed enough force highlights up to clipping. But taking Exposure down is clearly a pure "gain" control, and exactly the same as the Whites control (also a pure "gain" control) ... it drops the white point, and everything else in a straight line to the black point. While for many things Exposure for me isn't that useful, for your work, you might find it very useful.

Whites is as noted above a pure and easy to anticipate (therefore use!) gain tool. Shadows & Highlights both extend WAY past what you might think, so if you move one, you really probably need to work both.

Once you figure out how to use it, it's pretty decent though. And a BIG note ... if you're going to get much color work to do, you need to get at least a Tangent Ripple or a Palette tool. Having some sort of control surface properly set up gives you both faster work and better work, as when working two controls simultaneously, you see mid-corrections you can't see working one control at a time. It would at least double your speed in the first month. After that, you'd be at least four times faster in color work.

Next ... the White Balance section in the Basic tab only balances the whites & upper highlights. Watch the Parade RGB controls. Moving Temp changes the balance of the top of the red against blue channels, does not touch green. Tint changes the red/blue tops against the green top. Nothing happens in the shadows, maybe a small change in the mids, more as you get into the highlights.

If your clips are shot at different WB settings in-cam, this doesn't clean that up. So ... skip 'em.

After you've done your tonal work in the Basic tab, go to Creative, zero the Sat slider to get your color back, then use the Shadow 'tint' control to effectively neutralize the shadows by finding a major structure (shape) in the deep shadows that is there on all three Parade RGB traces, and working that Shadow Tint tool until the shapes line up across the bottom. Do the same in the Highlight Tint tool, and you've probably neutralized your whole clip.

Now use the Saturation and Vibrance controls to get your color amounts looking ... you guessed it, "normal" or neutral. Maybe add sharpness to one cam to match the look of the other at need. You should by this time be fairly neutral.

I'll have another series of posts on my recent changes in my neutralization work in Lumetri up over the next few days.

Neil