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Problems Of Dueling Colours

I've got a question here that my be a bit esoteric, but hang in there...

In dealing with super color saturated lighting, how do you combat unwanted complementaries from appearing?

For example -- in a recent sequence I was keying with a super saturated red - Rosco 27 on tungsten and filling with clean tungsten. Of course, the shadows went green (took on the property of the complimentary color). For this sequence that was okeydokey - but how would I avoid that? Would I have to fill with a less saturated red to avoid the green? Or should I fill with a yellow or amber (the secondary color) to counteract the green shadows? To make matters worse, in this particular situation, the background was white so the green really showed up...

I'll experiment with this a bit while I have a few days - but I was wondering about all of your thoughts. Anyone have a procedure for working with this?

Jay Holben Director of Photography


I can understand this occuring to your eye as the red cones get depleated from the super saturated red and your ability to auto correct gets wacked...but I've never seen this effect on film.

Glenn Suprenard Dir/DP


Actually it does, quite often. How many times have you been in a telecine or a printing session saying -- "There's still too much green!" and the colorist replies (especially in telecine when they're looking at a vectorscope) "But there isn't *ANY* green in there!!"? In seeing The General's Daughter in which Peter Menzies uses considerably saturated yellows, many of the skin tones do tend to take on a greenish hue, which he says he didn't mind. As a theatrical lighting designer (my past life) this was a considerable problem to be wary of - but I always felt it wasn't such a deal in film... now I realize that it can be an issue...

Jay Holben Director of Photography


Perhaps if the red was too saturated, the film timer/grader added some green to even it out, thereby adding some green to the "tungsten only" areas ? In telecine one could probably just tame the red channel's saturation a bit.

I find that red is also a difficult layer to expose correctly without testing the stock. If they had to print-up it might impart a slightly green cast. It'd be interesting to time to gray-scale and really see how the film was lit.

BTW, I too find there is sometimes a bit too much green in telecine that involves a lot of yellow/gold/straw colors. I'm always having them take out green while keeping it from hitting magenta.

Anybody ever notice that extreme red scenes have sharpness problems? Red scenes in "Carlito's Way" also comes to mind. Also very prevalent the way NTSC bleeds red.

Mark Doering-Powell


Yellow is an extremely difficult color to nail in NTSC, it seems to very quickly go green or red. Different brand broadcast monitors also vary in how they interpret yellow. I find that when setting SMPTE color bars in transfer or edit sessions there is always a compromise to be made between a good magenta and good yellow.

Perhaps that is what you are encountering with the yellow/gold/straw.

And why NTSC is referred to as Never The Same Colors.

Glenn Suprenard Dir/DP


 


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