Mike, here we go again.
If you are referring to WinDVD 3.0 this is no longer true. WinDVD 2.6.4 had the same problem as the ATI DVD player has with maintaining overlay settings. WinDVD 3.0 does not have this issue.
The gamma control on WinDVD acts the same as the one in the ATI player. From the leftmost step, the first increment to the right makes the image darker, the second is roughly the same as the leftmost step, and each sucessive step to the right makes the picture lighter.
You cannot just adjust the gamma control by itself.
1: Adjust the overlay brightness to avoid crushing the whites, using either Avia or VE. Use a horizontal step pattern or on Avia use the standard color bar pattern which has moving white and black bars in the lower area. The goal is to maximize the visable difference between the 90 and 100 IRE bars while maintaining the highest possible white level.
2: Adjust the white level on your projector or monitor to get the desired brightness of the brightest parts of the image, taking care not to push the white level past the point of maintaining focus.
3: Adjust the black level on your projector or monitor so that the pluge signals shows only a single bar. Use Avia or VE.
4: Now, and only now, adjust the gamma control so that shadow details that were not previously visable become visable. Use the VE montage of images or other dark material to check this. Do not overdo this adjustment!!!
If it is too high, you will start to see all kinds of MPEG artifacts!
5: Recheck the black level. If required, alternate between the gamma and black level adjustments to fine tune the image.
[This message has been edited by Vern Dias (edited 06-08-2001).]