how to change gamma when calibrating [Archive] - Calibration Forums

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calzone
03-24-2009, 06:20 AM
Quick question:

without much tweaking, my krp500a in ISF day mode gives fairly flat RGB curves from 10-100IRE, but with the red significantly higher than the G/B across the range. The gamma curves are slightly wobbly around a horizontal line but at about 2.1.

The obvious thing to do seemed to me to decrease Red High and Red low to lowe rthe red curve down to the G/B lines. This worked ok, but didn't help me on gamma. Is there anyway of tweaking greyscale that will "improve" gamma up to 2.22 nice and flat? e/g increase blue and green rather than decrease red?

I tried setting gamma 9pts to -1 across the board - helped somewhat raise gamma to 2.14 but feel its a bit less stable....

cheers

jmschnur
03-28-2009, 06:50 AM
According to Tom Huffman you set brightness to be a little less than .65 of your 100 IRE reading for 10 IRE. ( e.g. if 100 ire = 31 than 10 ire should be about .2. Exactly equal to .65% should give you a gamma of 2.2. If your meter is not sensitive enough to read the 10 IRE level than just play with brightness +1 - -1 and check the gamma settings.

joel