CurtPalme.com Home Theater Forum

[jbmeyer13]

I know there are many who think it's not necessary but for those who have adjusted it, what was your methodology?

I have inconsistent brightness/geyscale on the left center section of my screen. On the left grey looks more brown and on the right it has more of a white tone. I removed the contrast modulation board to see if it made any difference but it did not have any effect.

[Nashou66]

It's a pain...sorta... but i would use a full white field. Lower contrast to about 70% of where you normally keep it. So if you have it at 60 go to about 45, I think that is how the manual say's it should be done. The you can cycle through the colors by pressing the tint button with out changing the white field to another color. I'm at work now so can't remember the other remote buttons used to cycle the combination of colors and not move the zone being changed. Just play around with it , if it looks all screwy after just hit "0" and it set everything to default. Then start over. Sorry i cant get into more detail but been working 16 hour days since monday and no days off since Christmas.

I do need to redo my blend Zone contrast again one day. But i'll need 6-10 hours free

Nashou

[jbmeyer13]

Nash-

You'll never have 6-10 hours until you sell that joint. Sell or hire Craig;-)

[CIR Engineering]

If you want to try and mess with adjusting, the best thing to do is start by covering the blue tube with a lens cap. Adjust each red zone so that you get the best yellow uniformity you can achieve. Next cover the red lens and remove the cover from blue. Adjust each blue zone to get the best possible uniformity. Now look at white and touch up if necessary.

You might have to also use some green zone, but usually if the projector is centered you should not have to touch green, or at least touching green will make it even harder to even out red and blue to green.

There are better ways to adjust uniformity than with the CMM though anyway. I won't give up all my secrets on the forum

craigr

[jbmeyer13]

I have a feeling that the blue tube is causing the issue but we'll know for sure on 6/10:-)

[Nashou66]

One way to help out uniformity but many don't like doing it is make the raster a lot smaller. Towards the edge of the tube the light output drops off, so make that zone smaller and less issues arise.

Another thing you can do is like Craig said is not to use the CMM but instead use zone Astig and to some extent Zone Focus. But defocusing and making the dots a little larger and not perfect that is either making them taller or wider you can increase the light output in the color your lacking in that zone therefore correcting the brownish tint. I bet if you defocus the blue in that zone and maybe alter the Astig dot shape you might get a little better uniformity.

But this is all done as a compromise between sharpness and color uniformity.

Athanasios

[jbmeyer13]

[cmjohnson]

If you don't have a light meter, set up a full white field (or individual color field) and drop the contrast until the field is at the absolute threshold of vision. Just dim enough that you can barely see it when you're fully dark adapted. Then start adjusting the zone contrast until each zone is also at the threshold of vision.

This requires that you fully memorize the remote button sequences required to access the proper adjustments and make them. If you haven't memorized them that well, you'll have to bump the contrast up a few points to make the text readable, then put the contrast back down.

This approach works pretty well.


CJ

[Nashou66]