Setting Color with THX blue filter glasses
Once you've finished a good calibration run - you might want to look at the color/tint setting you've ended up with using your colorimeter vs. the one you'd end up with blue filter glasses. Then measure that again.
Someone else might comment on it and best practices regarding which one to pick in the end - but I found it useful to have two sets of parameters.
Greyscale has to be done prior to this using the meter.
The pattern you want to look at with your THX glasses is a color bar pattern - I recommend the one that comes with the AVS HD 709 disc called "flashing color bars" and the one that is on every Bluray produced by Sony/Columbia Studios ((preferably newer) James Bond movies f.e). To access the one on Sonys Blurays you have to type in the numbers 7669 followed by Enter in the main menu of the Bluray.
The guideline for setting Color/Tint with a blue filter is to reset the hue slider (most at least medium quality TVs come with the hue slider "somewhat properly set" and start from there (First move color, then tint if necessary, then both to see how they change in relation).
This way you are setting Color/Tint to minimize dE on the appearance of cyan/magenta (shifts are most noticeable for the human eye on those (using a blue filter) - thats why we use them and a blue filter).
Once you've set Color/Tint that way - measure again with HCFR and your colorimeter and compare your primary/secondary color readings as well as saturation and color checker values.
What I found useful getting this separate set of parameters:
My CIE triangle looks somewhat like this -
What you are seeing is a HCFR perfected setting with hue R1 (not 0) and color at 49 -
which for me produces the lowest dEs on prim/sec colors (avg), saturation sweeps (individual and avg) and Color Checker SC values (individual and avg). dE's of all below 3 except on 1 or 2 color checker values (highly saturated orange and a blue at 3,2 max) with dE avg being 1,3 on primaries/secondaries and avg 1,10 on color checker values. Saturation sweeps always sub dE 2 (mostly sub 1), with the exception of only blue 100% (slightly under dE 3). So a good (great) calibration.
greyscale is always sub 1,3 dE regardless of CIE76 or CIE2000 with most values sub dE1.
But notice that at cyan and magenta 100% saturation the points are a little bit off ("bent"). This is being introduced by using the R1 (hue) setting (slightly increased dE when measured, both to sub dE 2,5) - normally they would perfectly align with the other saturations.
Also notice that blue at 100% saturation is definitely "off target" as is red at 75% saturation. This is the "native characteristic" of the display I am working with - meaning, that those errors always show and I was compensating against them (with color and Tint settings).
When using the THX blue filter glasses, I ended up with a hue 0, color 53 setting, which would - perfectly align cyan and magenta at 100% saturation, would drop their dE errors to below dE1 (wow! blue filters work!
), but the display characteristics would suddenly "show more".
dE of blue 100% saturation would jump to 4,3 (seems about right from just looking at the CIE triangle in the first place)
dE of red 75% saturation would jump to 2,8 (most noticeably, because with the first setting it never got much above 2)
All other color points showed very nice values altogether, color checker SG average dE went up by 0,2, but mostly caused by some (few) breakout values at the high saturated orange range which suddenly jumped into dE 4,7 territory. While before those few breakout values were at dE 3,2 max.
So by all "best practice rules" of calibration, setting 1 would be the better one. Lower dE at all those points where it counts most (the higher ones..
), lower averages (even on color checker SG), even better saturation tracking. And primaries/secondaries > blue could be suppressed to just below dE3. Even skin tones look better and are lower dE.
Although I find the picture pleasing and looking great in most shots (I'd even say accurate) - there is a certain "rosé" tint on some pastel "not exactly white (warmer)" tones, that I'm very sensitive to, that doesnt show up in most scenes, but when it does - I notice it very strongly. It represents a "lack of green", and is fixed by just moving the hue R1 slider to the 0 position (color slider (a few steps) doesnt do much in this particular case).
Caveat: I have a red/green color "deficiency" (not exactly blindness) (damn you male gene defect!
) - so me so much noticing this "rosé" tint - might be related to that.
In setting 2 (because it uses hue at 0) this does not happen (but skintones are less "spot on" - *draaaaag*).
Blue filter assessments were done with a friend present who doesnt have a color perception deficiency - to make sure we both "see" the same "setting". Which was the case. ("I can use blue filters - whohoo!")