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gamma

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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

#39023 — gamma

This might not be completely on-topic, but I think I could get an answer 
here, one that might be better than elsewhere.

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 ?

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#39033

Askfor wrote:

> This might not be completely on-topic, but I think I could get an answer
> here, one that might be better than elsewhere.
>
> 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 ?

https://en.wikipedia.org/wiki/Gamma_correction

Took me literally 2 seconds of googling.

-- 
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#39035

Auric__ wrote:
> Askfor wrote:
>
>> This might not be completely on-topic, but I think I could get an answer
>> here, one that might be better than elsewhere.
>>
>> 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 ?
>
> https://en.wikipedia.org/wiki/Gamma_correction
>
> Took me literally 2 seconds of googling.
>

It took me even less, but it doesn't help

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#39064

On 2016-09-23, Askfor <askfor@nowhere.net> wrote:
> Auric__ wrote:
>> Askfor wrote:
>>
>>> This might not be completely on-topic, but I think I could get an answer
>>> here, one that might be better than elsewhere.
>>>
>>> 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 ?
>>
>> https://en.wikipedia.org/wiki/Gamma_correction
>>
>> Took me literally 2 seconds of googling.
>
> It took me even less, but it doesn't help

then play with gamma until you get an understanding.

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This email has not been checked by half-arsed antivirus software 

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#39048

Askfor wrote:
> This might not be completely on-topic, but I think I could get an answer
> here, one that might be better than elsewhere.
>
> 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 ?
>
>

I'll try to rephrase. If I increase gamma by 10% how much will 
brightness be increased approximately ? 10%, 40%, 70% ? What about 
contrast, will it decrease or increase ? How much ?  Saturation ?

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#39065

On 2016-09-23, Askfor <askfor@nowhere.net> wrote:
> Askfor wrote:

> I'll try to rephrase. If I increase gamma by 10% how much will 
> brightness be increased approximately ? 10%, 40%, 70%  ? What about 
> contrast, will it decrease or increase ? How much ?  Saturation ?

yes, all the above.  gamma is not a linear transformation on the
colour space, it effects light and dark areas in an opposite way.

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This email has not been checked by half-arsed antivirus software 

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#39069

On 09/23/2016 01:26 PM, Jasen Betts wrote:

> it effects light and dark areas in an opposite way

aaah, came the light - thanks.  I never really had much need to figure 
out a lot of graphic settings beyond bright and contrast - my 1st color 
monitor - a Sony - just worked and the rest (all Sonys + 1 LG) have as well.

This question just moved me back to 10% noob...

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#39056

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.



-- 
Mike Easter

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#39058

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

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#39059

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.

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#39060

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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#39057

On 9/23/16, 4:19 AM, in article ns33rb$q78$1@ls237.t-com.hr, "Askfor"
<askfor@nowhere.net> wrote:

> This might not be completely on-topic, but I think I could get an answer
> here, one that might be better than elsewhere.
> 
> 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 ?

If I understand correctly (and I might not!) brightness is, at least in
theory, linear... all levels of brightness on the screen are effected the
same: in other words both dark and light parts of the screen are brightened
(or made less bright).

Contrast works by making a bigger difference between dark and light areas...
but in a linear way (I think). It tends to make the near-whites and
near-blacks get pushed to the extremes and you lose details.

Gamma impacts both: the bright parts of the screen more than the dark... so
the curves you are seeing is showing how much more. Usually they show
brightening the black parts little if any and the white ones a lot with
those of different luminance values in some exponential way. This impacts
the contrast without "blowing out" the near-whites and near-blacks.



-- 
* OS X / Linux: What is a file?     <http://youtu.be/_dMbXGLW9PI>
* Mint MATE Trash, Panel, Menu:     <http://youtu.be/C0y74FIf7uE>
* Mint KDE working with folders:    <http://youtu.be/7C9nvniOoE0>
* Mint KDE creating files:          <http://youtu.be/N7-fZJaJUv8>
* Mint KDE help:                    <http://youtu.be/3ikizUd3sa8>
* Mint KDE general navigation:      <http://youtu.be/t9y14yZtQuI>
* Mint KDE bugs or Easter eggs?     <http://youtu.be/CU-whJQvtfA>
* Easy on OS X / Hard on Linux:     <http://youtu.be/D3BPWANQoIk>
* OS / Word Processor Comparison:   <http://youtu.be/w6Qcl-w7s5c>

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#39089

On Friday, 23 September 2016 17:27:31 UTC, Snit  wrote:
> On 9/23/16, 4:19 AM, in article ns33rb$q78$1@ls237.t-com.hr, "Askfor"
> <askfor@nowhere.net> wrote:
> 
> > This might not be completely on-topic, but I think I could get an answer
> > here, one that might be better than elsewhere.
> > 
> > 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 ?
> 
> If I understand correctly (and I might not!) brightness is, at least in
> theory, linear... all levels of brightness on the screen are effected the
> same: in other words both dark and light parts of the screen are brightened
> (or made less bright).
> 
> Contrast works by making a bigger difference between dark and light areas...
> but in a linear way (I think). It tends to make the near-whites and
> near-blacks get pushed to the extremes and you lose details.
> 
> Gamma impacts both: the bright parts of the screen more than the dark... so
> the curves you are seeing is showing how much more. Usually they show
> brightening the black parts little if any and the white ones a lot with
> those of different luminance values in some exponential way. This impacts
> the contrast without "blowing out" the near-whites and near-blacks.

Thank you. Good explanation and something I have wondered about.

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#39093

On 2016-09-24, tmelmosfire@gmail.com <tmelmosfire@gmail.com> wrote:
> On Friday, 23 September 2016 17:27:31 UTC, Snit  wrote:
>> On 9/23/16, 4:19 AM, in article ns33rb$q78$1@ls237.t-com.hr, "Askfor"
>> <askfor@nowhere.net> wrote:
>> 
>> > This might not be completely on-topic, but I think I could get an answer
>> > here, one that might be better than elsewhere.
>> > 
>> > 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 ?
>> 
>> If I understand correctly (and I might not!) brightness is, at least in
>> theory, linear... all levels of brightness on the screen are effected the
>> same: in other words both dark and light parts of the screen are brightened
>> (or made less bright).
>> 
>> Contrast works by making a bigger difference between dark and light areas...
>> but in a linear way (I think). It tends to make the near-whites and
>> near-blacks get pushed to the extremes and you lose details.
>> 
>> Gamma impacts both: the bright parts of the screen more than the dark... so
>> the curves you are seeing is showing how much more. Usually they show
>> brightening the black parts little if any and the white ones a lot with
>> those of different luminance values in some exponential way. This impacts
>> the contrast without "blowing out" the near-whites and near-blacks.
>
> Thank you. Good explanation and something I have wondered about.

Another snit sock puppet.
Are you guys getting this yet? 
I hope so.

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#39096

On Saturday, 24 September 2016 04:16:17 UTC, Jim Polaski  wrote:
> On 2016-09-24, tmelmosfire@gmail.com <tmelmosfire@gmail.com> wrote:
> > On Friday, 23 September 2016 17:27:31 UTC, Snit  wrote:
> >> On 9/23/16, 4:19 AM, in article ns33rb$q78$1@ls237.t-com.hr, "Askfor"
> >> <askfor@nowhere.net> wrote:
> >> 
> >> > This might not be completely on-topic, but I think I could get an answer
> >> > here, one that might be better than elsewhere.
> >> > 
> >> > 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 ?
> >> 
> >> If I understand correctly (and I might not!) brightness is, at least in
> >> theory, linear... all levels of brightness on the screen are effected the
> >> same: in other words both dark and light parts of the screen are brightened
> >> (or made less bright).
> >> 
> >> Contrast works by making a bigger difference between dark and light areas...
> >> but in a linear way (I think). It tends to make the near-whites and
> >> near-blacks get pushed to the extremes and you lose details.
> >> 
> >> Gamma impacts both: the bright parts of the screen more than the dark... so
> >> the curves you are seeing is showing how much more. Usually they show
> >> brightening the black parts little if any and the white ones a lot with
> >> those of different luminance values in some exponential way. This impacts
> >> the contrast without "blowing out" the near-whites and near-blacks.
> >
> > Thank you. Good explanation and something I have wondered about.
> 
> Another snit sock puppet.
> Are you guys getting this yet? 
> I hope so.

Can you try harder to miss the point?

Oh. You are just trolling.

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