[lovingdvd]

1) The Sharp 10000 provides the ability to adjust the gamma for red, green, and blue independent of each other. Under what conditions would it be appropriate to tweak these settings?


For example, I have a general understanding of why one would make tweaks to r,g,b gain/offset controls - but am wondering about the r,g,b individual settings for gamma.


I plan to get the ColorFacts CF-6000 soon and would like to know in advance what conditions to look for which may indicate/warrant that tweaks in a particular color's gamma level are needed.


2) The Sharp 10000 has a Color Management System (CMS) that enables you to adjust the luminance, chroma, and hue of R,G,B,Y,M separately. I would like to understand how to dial in this colors - in particular red.


I've noticed that with the out-of-the-box settings on this pj, its reds are way to hot/fluorescent. By eye, I tweaked it temporally so that red looks more natural by reducing chroma to -15 and increasing hue to +5. But this is mostly guesswork and I'd like something much more scientific...


a) With just something like Avia or VE (no test equipment like the CF6000) is there any test pattern I can use perhaps with the red filter to get an idea of how this needs to be set? I found what looked like a red color bar pattern that I looked at through the red filter but none of the changes I made to Red in the CMS caused the image to change.


If there is a pattern to adjust this please let me know more specifically which one it is and the overall procedure to follow to dial it in.


b) Same question as "a" above - except in this case *with* test equipment like the CF6000. So in other words what would be the process of dialing in red using CMS with a measuring device?


Thank you.

 

[jmschnur]

It would be best to get access to R contrast, G Contrast, and B Contrast, and their related RGB brightness controls and use color facts to set each based on the 30 and 80 IRE gray test patterns provided in Color facts for 6500 degrees based upon your device primaries.


.


Use the R Gamma, G, gamma, B gamma to adjust for 6500 using the 50 IRE pattern.

CYM is a different story-best ot leave these alone except for final tweaks. These can be done with the AVIA color bar patterns for blue, red, and green since the hue bars are cym.


Mark has a nice tutorial on this.


Joel

 

[lovingdvd]

Quote:

Originally posted by jmschnur It would be best to get access to R contrast, G Contrast, and B Contrast, and their related RGB brightness controls and use color facts to set each based on the 30 and 80 IRE gray test patterns provided in Color facts for 6500 degrees based upon your device primaries. . Use the R Gamma, G, gamma, B gamma to adjust for 6500 using the 50 IRE pattern. CYM is a different story-best ot leave these alone except for final tweaks. These can be done with the AVIA color bar patterns for blue, red, and green since the hue bars are cym. Mark has a nice tutorial on this. Joel

Ok so in summary use gain (contrast) for r,g,b on 80 IRE, use offset (brightness) for r,g,b on 30 IRE, and use gamma for r,g,b on 50 IRE.


However wouldn't changing the gamma for r,g,b affect the r,g,b contrast/brightness once changed?


Also can you point me to Mark's tutorial on this? I didn't see it on their web site but may have overlooked it. Thanks!

 

[NiToNi]

Hi lovingdvd,


With Colorfacts and Sharp Vision Manager, you can calibrate all three RGB colors tracking the same gamma curve and ideally one representing a gamma of 2.2 - 2.5. In the current 2.25 version of Colorfacts, the "Luminance Histogram" displays the gamma curve only for the three colors combined, but I believe that in the next update (v.2.5 due soon), this diagram will show each color seperately.

http://www.colorfacts.com/colorfacts...s/help0028.jpg


However, using the "RGB Levels Histogram", you can easily tell whether a color roll off at the high end, or if there is too much or too little blue at a given IRE level, etc. By tweaking gamma, you can achieve all three colors to be flat throughout the IRE scale (beware of trying to interpret too much into and correct for deviations in the lower end though unless you have assured sufficient light output for the meter to read accurately).

http://www.colorfacts.com/colorfacts...lHistogram.gif


Using C.M.S., you can tweak errors in the color decoder by using AVIA. Don't confuse this with setting the gray scale, as best explained by Guy Kuo here , here , here , here , and here .


Have fun with Colorfacts - you're going to love it!

 

[lovingdvd]

Quote:

Originally posted by NiToNi Hi lovingdvd, With Colorfacts and Sharp Vision Manager, you can calibrate all three RGB colors tracking the same gamma curve and ideally one representing a gamma of 2.2 - 2.5. In the current 2.25 version of Colorfacts, the "Luminance Histogram" displays the gamma curve only for the three colors combined, but I believe that in the next update (v.2.5 due soon), this diagram will show each color seperately. http://www.colorfacts.com/colorfacts...s/help0028.jpg However, using the "RGB Levels Histogram", you can easily tell whether a color roll off at the high end, or if there is too much or too little blue at a given IRE level, etc. By tweaking gamma, you can achieve all three colors to be flat throughout the IRE scale (beware of trying to interpret too much into and correct for deviations in the lower end though unless you have assured sufficient light output for the meter to read accurately). http://www.colorfacts.com/colorfacts...lHistogram.gif Using C.M.S., you can tweak errors in the color decoder by using AVIA. Don't confuse this with setting the gray scale, as best explained by Guy Kuo here , here , here , here , and here . Have fun with Colorfacts - you're going to love it!

Wow NiToNi - thanks for the tip and all the links!


I believe the latest version of ColorFacts posted on their site is 2.5 something. Does that have what is required to plot the r g b separately?


I'm a bit confused by the statement: "...you can calibrate all three RGB colors tracking the same gamma curve and ideally one representing a gamma of 2.2 - 2.5". Can you explain this some more?


Also what is the purpose of the Sharp Vision Manager software that came with my Sharp 10K. To use it do I need to be able to output via DVI to my Sharp 10K from my computer? I don't have a HTPC. What types of things is the Sharp Vision Manager good for and what if anything can it do that AVIA, VE, and/or ColorFacts alone cannot?


Thanks!