Greeno, I'm sorry to tell you that, but I checked the differential method and it doesn't work very well. Take a perfect 2.2 gamma dataset, sample it in a few points (the ones you get with Avia or DVE) and run the algorithm - you'll get a higher than 2.2 number. (I've checked it with DVE samples of 20,40,80,100 and got an error of ~0.2)

The reason is that Y1-Y2/(X1-X2) isn't really a dY/dx, but an approximation. Since we've got pretty few points, the total error is big. I'm guessing with Avia it will be smaller though (more sampling points).

The original raider's method (bar small number correction) combined with my BIAS/GAIN calculation gets much closer result (easily verified even visually comparing the reference and the acquired gamma graphs).

The reason is that Y1-Y2/(X1-X2) isn't really a dY/dx, but an approximation. Since we've got pretty few points, the total error is big. I'm guessing with Avia it will be smaller though (more sampling points).

**This method will work well when you have a lot of sampling points.**The original raider's method (bar small number correction) combined with my BIAS/GAIN calculation gets much closer result (easily verified even visually comparing the reference and the acquired gamma graphs).

Quote:

Originally Posted by

My "calibrated" settings that produced a green tint in blond hair and some explosion firelballs came about when using an old dtp-92 - not the current dtp-94. The way I got rid of the green was to use a calibrated meter, the dtp-94.

There was a clear green tint when I measured grayscale using the dtp-94 AFTER calibrating the set using the dtp-92. Re-calibrating with the dtp-94 solved the problem.

I did implement the main part of the differential method. Who cares about the intercepts? What we're after is the (gamma-1). that is what I've implemented.

Best,

jeff

**greeno**My "calibrated" settings that produced a green tint in blond hair and some explosion firelballs came about when using an old dtp-92 - not the current dtp-94. The way I got rid of the green was to use a calibrated meter, the dtp-94.

There was a clear green tint when I measured grayscale using the dtp-94 AFTER calibrating the set using the dtp-92. Re-calibrating with the dtp-94 solved the problem.

I did implement the main part of the differential method. Who cares about the intercepts? What we're after is the (gamma-1). that is what I've implemented.

Best,

jeff