Originally Posted by Seamonster73
Thats great. Thanks for that.
So just to check, if I wanted to check all of the primary/secondary saturation 25/50/75/100% points I should use the Color Checker Classic chapter from that disc (or Color Checker SG if I want to go into more detail)?
The reason I ask (and apologies if this is going off-topic slightly) is that I'm trying to to re-calibrate my 8-year old Pioneer Kuro PDP-508XD. As you've probably guessed I'm an 'enthusiast' not a professional and this is the only display I've ever tried to calibrate. The last time I did this was with HCFR v2.x (way back before Zoyd started updating HCFR) when the CIE diagram only showed the 100% Saturation targets. Having updated to the newest version, and from looking at 25/50/75% saturation targets (using AVSHD) I can see a problem with the display which I've suspected all along:
- The Pioneer 8Gs (and 9Gs) had a choice of 2 Colour Spaces - Colour Space 1 = 'Vivid' and Colour Space 2 = 'Rec709 Standard'
- Colour Space 2 should therefore be the one to use. However there was a problem with it on the 8Gs (Which was fixed with the 9Gs) in that if you set the colour controls to get the 100% Primaries in the correct xy locations (and use 21% * 100IRE to set red luminance etc) then the 25/50/75% points for all colours were all massively undersaturated. This wasn't visible (to me) in the old version of HCFR as the targets weren't shown on the CIE diagram, but it was obvious from looking at real world material that the resulting picture lacked colour.
- Therefore there seems to be no way i can get the colour 'correct'. Colour Space 1 actually seems better in many respects as it can be toned down to get close to Rec709, but has the opposite problem over being over-saturated at 25/50/75% (but without some of the luminance errors Colour Space 2 has).
But if I'm trying to decide which is the best compromise to make then I want to make sure I'm using the correct test patterns/targets. As such, I'll get your disc.
As a general question though - If it's a case of choosing between under saturated or over saturated is one considered to be better (or less worse) than the other? Or does getting the correct luminance for the 100% targets take precedence over any saturation issues? Or does it just come down to personal taste?
Or should I just run HCFRs colour checker tests with the Lightspace disc and try to get the delta errors as low as I can without worrying whether the errors are due to under/over saturation/luminance?
Sorry if the above is off topic for this thread. If there's a more suitable thread let me know and I'll edit the above.
Hi, to check your Color Saturation tracking you can run the 4/5/10-Point Saturation Run that is available in the disk.
About choosing which patterns you will use for Gamut calibration, think that the Luminance of 75% Stimulus Patterns has about 50% of the Luminance of 100% Stimulus (based on gamma 2.2), so your adjustment point is at the center of the color luminance range when you use 75% Stimulus patterns.
Using 100% Stimulus Patterns your adjustment point is at the highest end of the luminance range but you will probably have larger errors at lower luminance levels.
This works for some displays / don't work to others.
When you have to calibrate a display using it's internal available calibration controls, because the gamut control points are only a few (1-Point per color) you have to try to find out which patterns you have to use for your gamut calibration.
There is not any golden rule which says which type of patterns to use to calibrate the CMS for each display model, you have to try to your display these 4 options.
(75%/75% - 75%/100% - 100%/75% - 100%/100%) to find out which type of patterns will provide you lower dE overall, try to calibrate based to one of these options (for example 100SAT/75AMPL) and at the end, measure using 4-Point Saturation / 4-Point Luminance / ColorChecker / Fleshtones.
Later re-calibrate your display using another option (for example 75SAT/75AMPL) and remeasure at the end with Saturation/Luminance/ColorChecker etc... and compare these 2 reports to see what patterns are providing you lower dE numbers.
The average Caucasian skin tone resides well away from any grey scale, or primary color. That's why you have to check ColorChecker because it contains skin tones, grass, sky, etc, which are memory colors...the human eye has a better idea as to what they should look like as they are seen almost daily.
Initially it will take some time to measure these 4 pattern options to find which patterns are providing better performance but next time you will know which patterns to use for that specific display you are calibrating.
This is happening becasue you have only 1 control point for each color of Gamut Calibration, so you have to find which point you will use (% Saturation/ % Luminance)...think that you have a display with 1-point Grayscale.....where you have to test to see which grayscale pattern will balance better the whole grayscale and provide the lower errors, from 10% Gray till 100% White.
Propably it's better to do 75% SAT / 75% STIM or 75% SAT / 100% STIM calibration, where you will improve the color tracking of primary color saturations internally; which is more important from having better performance (less dE errors) only to the gamut edges (100% Saturation).
KURO don't feature full CMS for Gamut calibration, it has only Hues control and you will use the Color control which add/remove Luminance to all primary colors. Recommended adjustments for Hues are +-1 only, more adjustment will break the linearity of Luminance/Saturation tracking. Once you will be ready with Hues adjusments measure the Gamut with Color 0 the 5-Point Saturation and Luminance measurements runs and ColorChecker Classic or SG....save that report.....redo the same with Color +1, later with Color +2, later with Color +3....and at the end compare the reports and choose the one with less average dE errors.
Use ColorSpace 2 which is covers better the REC.709, the ColorSpace 1 is the native gamut which is larger from REC.709, since you don't have Saturation adjustment, you can't de-saturate any primary using ColorSpace 1.
Using ColorChecker SG you will have a better overview of your display performance since it's including a lot of skintones and memory colors.
Here is the ColorChecker SG in 3D Cube RGB space presentation:
For problematic displays where you want to have the best possible performance at every area, you have to move to 3D LUT calibration/profiling, this correcting multiple saturation/intensity/hue levels.
To visualize the difference between Normal 1D LUT vs. 3D LUT calibrations at various Cube Sizes you can see these Cube Size Comparison Pictures