CompuServe Messages

This message is regarding Video and the Targa 32/64+ and gamma adjustment. Only RGB and SVGA can be gamma adjusted with the Boxes to be able to visually see Gamma Adjustment. In other words only through your SVGA or RGB monitor will the boxes line up! NTSC will not show proper Gamma alignment with the boxes. If you set it to 1.0 where the boxes match, you have effectively disabled or neutralized Gamma Correction in NTSC. You can check this by rendering ADLOGO at 1.0 with Gamma on and then re-rendering with Gamma off. They are identical. If you set your framebuffer Gamma to 2.2 you will not see boxes that match on your NTSC monitor but your NTSC will be gamma corrected. In fact on your NTSC monitor the inner box will be bright. RGB and SVGA will Gamma correct in that the boxes will match. I would recommend that you make your gamma adjustments for either of these two monitors or between 1.8 – 2.2 to suit your taste. While not explicitly stated the Advanced User Guide does say "The standard gamma value for NTSC video output is 2.2", it does not state however how one is supposed to arrive at that, and the assumption has been that by getting the boxes to match up you would have proper gamma adjustment. This assumption is incorrect. This only works for RGB and NTSC. You also need to check your recording device to make sure it doesn't gamma correct. Otherwise you run the risk of double correcting.