POV-Ray : Newsgroups : povray.binaries.images : Lego rescue vehicles : Gamma? Server Time
4 Nov 2024 13:13:18 EST (-0500)
  Gamma?  
From: TC
Date: 2 Apr 2010 16:44:14
Message: <4bb6571e@news.povray.org>
> I percieve the stretcher-user's face as too greenish, too.

I have done a bit of measuring. You are right, there is a bit of green 
in the victims face. I am posting a screencopy of the face to show you 
what line I used to sample the colorvalues (red rectangle, pixels from 
right to left):

I first did measure the original png-picture. 

<128, 128, 1>, <255, 255, 27>, <255, 255, 59> (9 pixels, same value)

Then I measured a screencopy of the png-file as displayed in Outlook 
express:

<117, 117, 1>, <255, 255, 20>, <255, 255, 49> (9 pixels, same value)

Conclusion: when >I< display the picture my gamma-correction seems to 
take out around 20% of the blue colour value. So I do perceive the 
yellow less green-ish than you do, probably.

I would be intesting to know what you measure.

Please do a really strong zoom on this picture to see what area I used - 
if you are interested in comparing the png-colour values to screencopy 
values on your computer at all.



I never thought about this, but obviously every time you do a screencopy 
and save the picture, gamma-correction alters the colours. Makes perfect 
sense when you think about it - but I have to say I never thought about 
this fact at all.


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