I do my first calibration with my Z12000 and there were two problem cannot resolved at the moment. I am using ColorHCFR 2.0 and Eye One Display to calibrate.

1. A bit red cast when I set the grayscale, the red gain pushed almost max to match other two channels in 80% IRE. The result gamma cannot fit perfectly on 2.2 curve.

2. Green primary has problem, it is impossible to set it to the right position on CIE diagram.

Default setting
http://www.av100fun.com/download/file.php?id=227387

After calibration
http://www.av100fun.com/download/file.php?id=227388

Does anyone has idea what's going wrong with my setup? Thanks in advance!

Greetings

You cannot magically add all new colors into the projector. If Green starts off outside what is possible ... it stays that way.

regards

greetings

From a calibration perspective, one should almost never increase any of the gain controls when doing grayscale.

Once you set your contrast and your brightness right ... then you tackle grayscale. Not to be done prior to that.

regards

greetings

From a calibration perspective, one should almost never increase any of the gain controls when doing grayscale.

Once you set your contrast and your brightness right ... then you tackle grayscale. Not to be done prior to that.

regards

Hi Michael,

For the grayscale, if I don't use the gain control adjusting the Red and Blue channel, I cannot get their level matched in 80 IRE screen, which is from gamma adjustment. Is there any method I can adjust gamma without altering gain setting?

For the contrast, I am using AV709 while level 230-253 screen to calibrate. Should I max out the contrast to make white levels clips after 235 or I should left my project's contrast as it which can show all white level from 230-253.

Greetings

For contrast ... you want to see all the way out to the end.

Get Brightness and contrast set up right ... most times ... that takes care of any big gamma issues too. Need to get steps 1 to 20 right first before complaining about how step 21 seems off. You can't fix 21 until the other 20 steps are done correctly first. :)

One has to remember that Gains are contrast controls. If you boost them, you boost contrast and just start the cycle of clipping all over again. Dog chasing tail. Hence once contrast is set ... you have defined the clipping point and the discoloration point and so forth. Then you know not to exceed that. (Line of Death)

regards

Understood, that means I should first setup the overall brightness and contrast first, do the readings again. If the gamma does not have big problem, I should leave it as is but not messing up with the gain and offset in the RGB setting.

I will try again and see which should give more appropriate outcome. Thanks for your advice.

I have a 12kMkII and my green is exactly the same. It seems to be limitation of the projector and can't be corrected. As for the greyscale, I seem to remember having to lower the green controls almost all the way down to get the greyscale right. Instead of raising red, try lowering green and blue.

Rob

I have a 12kMkII and my green is exactly the same. It seems to be limitation of the projector and can't be corrected. As for the greyscale, I seem to remember having to lower the green controls almost all the way down to get the greyscale right. Instead of raising red, try lowering green and blue.

Rob

Thanks Rob. As I followed the tuning guide for dummies for not to touch the green channel (as it use green as reference). I definitely try again to when I have time. :)

After recalibrated the projector all over again, I managed to improve the colour accuracy a bit (even though the problem on green cannot be fixed due to hardware limitation).

Greetings

For contrast ... you want to see all the way out to the end.

Get Brightness and contrast set up right ... most times ... that takes care of any big gamma issues too. Need to get steps 1 to 20 right first before complaining about how step 21 seems off. You can't fix 21 until the other 20 steps are done correctly first. :)

One has to remember that Gains are contrast controls. If you boost them, you boost contrast and just start the cycle of clipping all over again. Dog chasing tail. Hence once contrast is set ... you have defined the clipping point and the discoloration point and so forth. Then you know not to exceed that. (Line of Death)

regards
So if we have a set where we've lowered conrast until red stops "running out," and then move on to grayscale, and at the top end (say 80%) blue and green are ok but red is low, we should lower the green/blue gains rather than raise the red gain?

Greetings

Yes ... better to lower than to raise on the bright end of things. If you raise the red ... you have to lower the contrast to compensate ... (Which is just you lowering red / green / blue at the same time.)

Regards

and if red is low at the low end too, ok to raise bias?

Greetings

On the dark end .. go up or down as needed and double check the brightness afterward.

regards