Gamma Correction for Images and Video

Images that look good on your workstation screen will probably appear too dark if recorded onto video tape or on a hardcopy output device such as a dye-sublimation printer or a slide recorder. To solve this problem you must gamma correct the images before recording them. Each output device has a different intrinsic gamma and therefore requires a different correction.

I use the following procedure to gamma correct images:

This procedure won't work for recording live demos with the Lyon-Lamb (since you can't run gammawarp on a video stream!). For this situation, just set your monitor gamma to 2.2. You may also want to change the RGB output pedestal (the video signal level for zero) on the Lyon Lamb. To do this using the menus on the front panel of the Lyon-Lamb: choose the "Output" menu, hit the "Next" button to go to the next page of options, and choose "RGB Ped". The default is 0 IRE. Try choosing 7.5 IRE instead.

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Last modified: Mon Nov 2 15:34:55 PST 1998

Phil Lacroute