View Full Version : technical gamma question


thomasl
04-02-08, 08:25 PM
I have a question for the gamma experts. If I take a reading of a blue 75 percent intensity window pattern and then a reading of a 100 percent intensity window pattern, is the ratio of these two readings (75 / 100) defined by the overall gamma value at 75 percent intensity or is it defined by the blue only gamma value at 75 percent intensity? Or am I wrong on either count?

For example, if I have a Y reading for 100 percent blue of 10 and my gamma value at 75 percent intensity is 2.25 overall but the blue component is lower at 2.05 according to the software. So, does this mean that Y for 75 percent blue will be 5.23 or will it be 5.54?

thanks much,


--tom

sotti
04-02-08, 10:35 PM
I have a question for the gamma experts. If I take a reading of a blue 75 percent intensity window pattern and then a reading of a 100 percent intensity window pattern, is the ratio of these two readings (75 / 100) defined by the overall gamma value at 75 percent intensity or is it defined by the blue only gamma value at 75 percent intensity? Or am I wrong on either count?

For example, if I have a Y reading for 100 percent blue of 10 and my gamma value at 75 percent intensity is 2.25 overall but the blue component is lower at 2.05 according to the software. So, does this mean that Y for 75 percent blue will be 5.23 or will it be 5.54?

thanks much,


--tom


if blue is at 2.05 gamma @ 75% then it will be 5.54.

But since the 2.05 is an average, it may or maynot be 5.54

thomasl
04-05-08, 02:29 PM
if blue is at 2.05 gamma @ 75% then it will be 5.54.

But since the 2.05 is an average, it may or maynot be 5.54

Thanks Sotti,

This is what I thought. I then took the next step in my thoughts and realized that this means that one's gamma response can have an impact on color brightness response. Thus if you adjust your color brightness control using 75 % patterns so blue is perfect, it may not be perfect anymore if you then alter your gamma response for blue at 75 %. I guess I could do an experiment to see if this is actually true.

cheers,


--tom