James Zos
Supporting Actor
- Joined
- Jan 7, 2002
- Messages
- 725
I can't take credit for this method, because it was sent to me by another HTF member who wishes to remain anonymous. It is, of course, not the same thing as getting an ISF calibration, but if you are short on funds and live in hicksville like me, it may be the next best thing. I've tried several different ways of eyeballing grayscale and this has given me the best results so far (though my color decoder is still off slightly.)
Here's the method, as sent to me by a valiant fellow member who deserves a lot of thanks. (Note: on my set, step 8 did not work exactly as planned. Increasing blue drive from zero did not bring the square towards gray. I had to bring blue cut up from zero first, before this would work. But everything else went fine. After several attempts at this method, my picture looks a hell of a lot better than it did before.)
Gray Scale Procedure
I have had success with the following procedure getting with in 500-1000K of the correct balance. It keys on the acute sensitivity of the eye of yellows being green or red. The final blue adjustment is the most difficult part. You need to be careful not to add to much. Even if you think you have it right you can use this to check it.
GOOD LUCK!!!
An instrument free procedure for adjusting white balance:
1. Place a bright gray window (~70 IRE) on the screen from AVIA or VE.
2. Drop your blue drive and cut to zero. Hopefully it will go low enough to not interfere.
3. Adjust the red drive until the window looks pure yellow (not green or red tinted).
I record the values where it looks slightly green and red and then try the values near the middle of those.
4. Place a gray scale ramp (100-0 IRE) on the screen.
5. Adjust red cut and green cut if you see a problem with low IRE yellows. This is difficult to judge.
6. Go back to step one if you changed either the green or red cuts.
7. Change the gray window to a value of around ~60 IRE.
8. Set the blue drive to zero and then increase the blue drive until the screen just looks gray and stop.
I use a photographic gray card with either indirect outside lighting or a 6500K light source to judge this.
Be very careful not to make the grays overly blue.
9. Place a gray scale ramp (100-0 IRE) on the screen.
10. Adjust blue cut if you see a problem with low IRE grays.
11. Go back to step 7 if you changed blue cut.
12. Readjust the color decoder if you have done this previously.
Here's the method, as sent to me by a valiant fellow member who deserves a lot of thanks. (Note: on my set, step 8 did not work exactly as planned. Increasing blue drive from zero did not bring the square towards gray. I had to bring blue cut up from zero first, before this would work. But everything else went fine. After several attempts at this method, my picture looks a hell of a lot better than it did before.)
Gray Scale Procedure
I have had success with the following procedure getting with in 500-1000K of the correct balance. It keys on the acute sensitivity of the eye of yellows being green or red. The final blue adjustment is the most difficult part. You need to be careful not to add to much. Even if you think you have it right you can use this to check it.
GOOD LUCK!!!
An instrument free procedure for adjusting white balance:
1. Place a bright gray window (~70 IRE) on the screen from AVIA or VE.
2. Drop your blue drive and cut to zero. Hopefully it will go low enough to not interfere.
3. Adjust the red drive until the window looks pure yellow (not green or red tinted).
I record the values where it looks slightly green and red and then try the values near the middle of those.
4. Place a gray scale ramp (100-0 IRE) on the screen.
5. Adjust red cut and green cut if you see a problem with low IRE yellows. This is difficult to judge.
6. Go back to step one if you changed either the green or red cuts.
7. Change the gray window to a value of around ~60 IRE.
8. Set the blue drive to zero and then increase the blue drive until the screen just looks gray and stop.
I use a photographic gray card with either indirect outside lighting or a 6500K light source to judge this.
Be very careful not to make the grays overly blue.
9. Place a gray scale ramp (100-0 IRE) on the screen.
10. Adjust blue cut if you see a problem with low IRE grays.
11. Go back to step 7 if you changed blue cut.
12. Readjust the color decoder if you have done this previously.