Originally Posted by Clemery76
I have finally picked up the reigns again and had another crack at calibrating the greyscale. I chose THX for now since I felt I got it close before, but it is still a little yellow for my liking, and will move to Movie mode next. I have attached before and after chc files if you're curious, as I think I got it reasonably close, but I won't actually be sticking with this mode I think.
Before going further, I did have a couple of general questions I wanted to ask to gauge the general opinion.
1. When adjusting the RGB values in the HI-LO or 10-point greyscale settings, do you adjust the GREEN to help get all three level at 100%(ish), or do you all try to leave green alone? I have read in a few guides that we should try to avoid adjusting green, instead only adjusting the red and blue values to get them close to 100%. If I do that, green is typically around 96% at best, while red is around 100 and blue is 110 or more. When increasing green I can get them all close to 100%, but as usual this requires the green and blue values to be pretty much maxed out to +30 and -30 respectively.
2. When adjusting the RGB values in the greyscale, is the goal in each step to get the dE number as low as possible, or to a certain level?
3. How much are skin tones affected by greyscale vs CMS settings? The THX calibration attached has left skin tones appearing mostly greeny yellow with magenta blemishes. I have not adjusted any CMS colour settings yet, but was just curious whether they can be used to correct skin tones without affecting the general colours too much. What about the tint control? The guide suggests that tint works for YCM the same way colour affects RGB... do people use it much to control skin tones?
4. When I was previously adjusting the CMS settings in my earlier calibrations of other modes, I was able to adjust the luminance values to the relevant levels... but when trying to adjust the hue/saturation to tweak the x/y values, I found the luminance was drastically affected. Is the goal to get all three (x/y/Y) as close as possible? I found I had to make some extreme changes to get all three close (like green brightness nearly maxed at +28, while most other colours were also a little extreme in the negative range), yet when keeping the green luminance within range, I could get the x/y values reasonably close, but not quite as close when the green luminance was high.
5. It seems recommended to adjust colour using 75% values... are there set x/y/Y targets for 75% colour patterns? It should be noted for all the above that I am using AVSHD patterns via USB on my Pioneer BD player.
Sorry... I seemed to have asked a lot more than I was originally intending to, but still just trying to get my head around it!
Thanks in advance!
I highly recommend you take a look at this post
and follow the "mini guide". This is a priceless guide that works really well for difficult to calibrate displays like the Sharp.
Really focus on the dE instead of the other values. What I have found to be useful is setting "measures/parameters/number of saturation color levels" to 10 instead of 4. This way you can focus on the "average dE" for any given color. For example (take red for example), go to measures/saturations/red and run the test. You will get the results for 10 points of saturation for red. You'll notice there is an average dE in the results. You can also see the results on the CIE diagram (this is especially helpful). After examining the results, adjust either Hue or Saturation based on the results on the CIE diagram to get the average dE even lower (don't focus on a specific saturation % only focus on average dE for entire 10 points).
Here is a helpful tool to use to adjust the CMS:
You can apply the same principle for "average dE" to the gray scale results. Make minor adjustments until your average dE for the entire spectrum is lower. Not just a specific point.
Again, study that guide and post (in fact read through those posts back in May and June when I was getting help with this same type of questions). Afterward, start adjusting grays scale but stick with 2 point (I have a feeling you'll get better results with your 2 point adjustment on the Sharp). Then see if adjusting contrast lower positively affects average dE for gray scale. I lowered my contrast until I saw diminishing returns but was still not clipping. Leave brightness alone... use the backlight to adjust luminance for now (beware of clouding). Get your gray scale average dE to be lower than 2 (with no point higher than 4). Then move onto CMS... don't dwell on gray scale because once you make adjustments to CMS it will affect gray scale... so you'll have to go back and forth a few times.
But as mentioned by others, it might be beneficial to start over and set all to factory defaults. Then pick a mode that you are going to stick with. No sense in getting pretty far with one mode just to switch to the other mode. THX mode is not recommended (it is usually limited in its ability to make adjustments by manufacturer). I'd go with Movie mode in almost all circumstances with a Sharp. Turn off active contrast, expanded color gamut, film mode, resolution enhancement, noise reduction, etc.