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Re: gamma

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On 9/23/16, 10:55 AM, in article ns3qbi$4dk$1@ls237.t-com.hr, "Askfor"
<askfor@nowhere.net> wrote:

> jrg wrote:
>> On 09/23/2016 10:15 AM, Mike Easter wrote:
>>> Askfor wrote:
>>>> What is gamma, related to imaging and monitors ? Most explanations
>>>> include some graphs, but how does it affect my visual experience ? How
>>>> is it related to common visual attributes, like brightness, contrast and
>>>> saturation ? Is there some sort of method to translate gamma into some
>>>> combination of those three ?
>>> 
>>> Should we assume that you already know/understand what the wp article on
>>> gamma correction says?  It is brief but gives a useful overview.  Pieces
>>> of two sentences pasted behind the link:
>>> 
>>> https://en.wikipedia.org/wiki/Gamma_correction  Gamma encoding of images
>>> is used to optimize the usage of bits when encoding an image, or
>>> bandwidth used to transport an image, by taking advantage of the
>>> non-linear manner in which humans perceive light and color. ... If
>>> images are not gamma-encoded, they allocate too many bits or too much
>>> bandwidth to highlights that humans cannot differentiate, and too few
>>> bits or too little bandwidth to shadow values that humans are sensitive
>>> to and would require more bits/bandwidth to maintain the same visual
>>> quality.
>>> 
>> 
>> Oh, now I see... :-p
>> 
> 
> I have found several articles. Very simplified, gamma is like contrast,
> but isn't linear, double gamma doesn't mean double contrast.
> 
> Generally, one can adjust monitor with gamma+brightness or
> contrast+brightness combinations. That information is of practical value
> to me at the moment. The rest of it, not so much.
> 
From what I understand brightness and contrast are linear... meaning they
have no differentiation in how they deal with darker or lighter areas. This
means both can lead to near-whites or near-blacks being pushed to those
extremes and you lose details.

Gamma makes does not do much for the blacks and whites and those things near
black and white. What it does is effect those things in the middle... with
the biggest difference being somewhere near a mid-gray. Those are made
brighter quite a bit... and the further from that midrange (which you can
set) and the closer to the end-ranges the less they are impacted.

I am sure there are details I am missing... but that is my understanding.


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gamma Askfor <askfor@nowhere.net> - 2016-09-23 13:19 +0200
  Re: gamma "Auric__" <not.my.real@email.address> - 2016-09-23 14:10 +0000
    Re: gamma Askfor <askfor@nowhere.net> - 2016-09-23 16:50 +0200
      Re: gamma Jasen Betts <jasen@xnet.co.nz> - 2016-09-23 20:23 +0000
  Re: gamma Askfor <askfor@nowhere.net> - 2016-09-23 18:00 +0200
    Re: gamma Jasen Betts <jasen@xnet.co.nz> - 2016-09-23 20:26 +0000
      Re: gamma jrg <connyank@cox.net> - 2016-09-23 14:48 -0700
  Re: gamma Mike Easter <MikeE@ster.invalid> - 2016-09-23 10:15 -0700
    Re: gamma jrg <connyank@cox.net> - 2016-09-23 10:32 -0700
      Re: gamma Askfor <askfor@nowhere.net> - 2016-09-23 19:55 +0200
        Re: gamma Snit <usenet@gallopinginsanity.com> - 2016-09-23 11:05 -0700
  Re: gamma Snit <usenet@gallopinginsanity.com> - 2016-09-23 10:27 -0700
    Re: gamma tmelmosfire@gmail.com - 2016-09-23 21:06 -0700
      Re: gamma Jim Polaski <jpolaski@linuxmail.org> - 2016-09-24 04:16 +0000
        Re: gamma tmelmosfire@gmail.com - 2016-09-24 00:58 -0700

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