Björn Benckert
Well-known member
First - RED color science prior to IPP2, was, no offense to Graeme, less sophisticated than ARRIs. Hardly a shock since ARRI had an entire team that spent years refining the color rendition of the digital files from their film scanners. Additionally, as others have noted, ARRI tweaked their color matrix in specific ranges to rein in certain hue/luma combinations that would rarely be desired. IMO, this is pretty subtle and for typical narrative work 90+% of the tweaks are what you'd want anyway.
Here's a supposition I'd love to try and prove with proper testing: ARRI's color matrix sacrifices some color precision in and near common skin tones to reduce the deviation threshold, RED's color matrix is simply trying to nail scene referred values. Wouldn't such "tweaking" create odd color shits on Alexas? I think it will, but not by much - and if you never saw that scene in real life, how would you know? Skin tone, OTOH, is something humans are evolutionally trained to perceive very precisely (interesting subject, but beyond this thread), so even subtle shifts are easily noticed.
When making the leading lady look her best, or the model for the product look radiantly healthy, etc is your task as a DP - a little bias toward skin tone rendition sounds like a plus.
It's also worth noting that during production, not always but typically, the image on the monitor is king. You can explain grading, gamma curves, rec709 color, ambient light, debayering and a hundred other things but, especially on spots, the WYSIWYG expectation persists.
Cheers - #19
Yes, this is according to my uderstanding as well.
I have not read enough of Graemes white paper to know for sure, but as Im told red IPP2 colors is pure mathematical curves, no color warping as in warping the shape of the color cube. To me that is a more "accurate" way of doing things than creating a 3D lut that push/pull the colors around. As I understand Arri is doing.
What fascinate me the most is how Kodak, Fudji and the others could 1. even get a colored image out of a plastic strip and silver flakes. Then imagine to make all that, mixing chemical liquids etc so it looks better than real.... To me thats quite an accomplishment. doing it digital seams so much more easy, but I guess not.


