[megacz]

Ever since repairing my 6PG, it seems that the colors are off -- stuff is a bit too red, and I've lost the definition I used to have in dim areas.


Instead of just fooling around with the controls and guessing, I was wondering if there is a 'procedure' for correcting color errors. I've seen a lot of computer monitors that come with a little card you place on the screen, and then tune the screen against the colors on the card -- is there a similar procedure for CRT's?


Any FAQs on the web about this?


Thanks.


- a

 

[DMan]

The most reliable way to adjust this is to use a color analyzer, or hire a technician who has a color analyzer as these devices are not cheap!


However, to get you by until you can have your unit professionally color calibrated, I would get the AVIA setup DVD. Then go under video test patterns and put up a 10 Step IRE vertical Gray ramp test pattern. This test pattern begins at the left with white (100IRE) and goes down to black (7.5IRE).

http://personal.atl.bellsouth.net/at...rn/10stepv.gif


Now using the White Balance adjustment in the 6PG's adjust menu, you can now adjust the White (W) level and Black (B) level for each of three tubes Red, Green and Blue. When making these adjustments, be sure to look from the middle of the test pattern (50IRE) and over to the left (100IRE) when adjusting the White level for each color. Then when adjusting the Black level for each color, look from the middle of the test pattern (50IRE) and over to the right (7.5IRE).


Make sure that each grayscale bar from white to black is distinctive enough from the next bar. And look for any amount of red, green, or blue color within the bars, and correct the white and black levels to maintain a good grayscale.

 

[GScott]

Thanks DMan. That is probably the best, to the point, instructions I have read.

 

[stefuel]

DMan,

Where is a good place to start. My 9PG Plus projector showed up with all w and b settings at 50%. No detail in dark areas and flesh tones look more red. Are you talking about running one color at a time making adjustments for black and all three for white or am I missing something. What are typical numbers for this PJ with 5,000 hr tubes? I've never tried the by eye gray scale methode. Thanks,


Chip S.

 

[shanemac]

...I have to say Dman is one of the best - not only are his instructions very readable, but they make sense to the average joe! (you don't have to be a ISF tech to read and apply)


a very talented and helpful individual indeed - the CRT forum wouldn't be the same without you Dman - just letting you know I appriciate all the help you've given me in the past.


Thanks again.

Shane

 

[DMan]

Quote:

Where is a good place to start. My 9PG Plus projector showed up with all w and b settings at 50%. No detail in dark areas and flesh tones look more red. Are you talking about running one color at a time making adjustments for black and all three for white or am I missing something. What are typical numbers for this PJ with 5,000 hr tubes? I've never tried the by eye gray scale method

Chip,


I don't really recommend doing this by eye, but without a technician's expertise and the right equipment, this is the next best procedure IMHO. To start with make sure you have the Contrast and Brightness set properly. Again, I would turn to the AVIA DVD and use the Needle Pulse Pattern seen here...

http://personal.atl.bellsouth.net/at...Brightness.jpg


The bars on the right hand side of the screen move back and forth so they can be easily seen. To adjust the brightness (black level) look at the top half of the screen at the black moving bars and adjust the brightness until the left bar is the same shade as the background and only the right bar is visible.


Now to adjust the Contrast, again look at the white moving bars at the bottom right and adjust the Contrast until only the left bar is left visible and the right bar becomes the same shade as the background. You may have to go back and forth between the Contrast and Brightness until you achieve the proper levels.


Another tip regarding this procedure, if both black bars are not visible then the brightness is set too low. If both black bars are visible then the brightness is set too high. The opposite is true with the Contrast. If both white bars are visible then the Contrast is set too low. If both bars are not visible then the Contrast is set too high.


Now that you have Contrast and Brightness set properly, now you can put up the Vertical 10 IRE Steps pattern and again try to adjust out the White and Black levels to achieve gray steps that do not contain shades of anyone of three dominant colors (RGB).


Hope that helps a little.

 

[DMan]

Shane,


Thanks so much for those kind words! I am humbled by the presence of a lot of the knowledge on this forum. For me to give some knowledge back to others is what makes this forum what it is today.


Again, very kind of you to take the time to write such a nice post. You are yet another nice individual that makes this place a pleasure to return to everyday.


Thanks again,