[HLSL CODE] Eye Adaptation

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*sensei*
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Joined: 28 Jul 2013, 23:26

Re: [HLSL CODE] Eye Adaptation

Always use 709...
I think adaptation texture is just a downscale fullscreen to 1x1 texture, that's why there's also no difference between using txcoord.xy and 0.5. Not sure if it's already passed a grey conversion... would be easy to test by just rendering the adaptation texture to fullscreen...

return tex2D(_s4, 0.5);

I don't think it went through some conversion (but could be wrong), naturally rendering screen to 1x1 will be some shade of grey. But if it didn't go through a conversion it should be blue-ish when looking at the sky and green-ish when looking at grass, instead of different grey intensity. Seems illogical if it's already greyscale since some max(max()) is applied on the vectors in the default files... would be kinda useless in greyscale.

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*blah-blah-blah maniac*
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Joined: 05 Mar 2012, 02:08

Re: [HLSL CODE] Eye Adaptation

I did do that and comparing the images (they where grey, slightly different between each) and when I compared tex2D(_s4, 0.5).y vs greylum(tex2D(_s4, 0.5).xyz) they had the same visual appearance and same histogram data. The "greylum" was using the max(max(inColor.x, inColor.y), inColor.z)
Those two where the same, while Rec.709 had slightly different shades as was to be expected.

But it is not greyscaled, I just jumped to a conclusion a bit too hasty. And yeah from what I can tell it's a 1x1 texture.
Always use 709...
Yeah, that really depends. But most work is done in regular RGB space and with displays that are aimed for the Rec.709 coefficients so it's the best approach to take, most of the time.

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*sensei*
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Joined: 28 Jul 2013, 23:26

Re: [HLSL CODE] Eye Adaptation

well I assume nobody is using CRT these days besides some very specialist applications :) consumer HD monitors are what to take into account, everything else is exceptional... But 709 is the most boring when it comes to B&W conversion. I don't like the contrasts it gives, it's too "flat" in lack of a better English word to my knowledge.

If it's not grey, you still need to pass the adaptation over a dot product to get luminosity coefficients, if you don't then adaptation will probably overreact to sky

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*sensei*
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Re: [HLSL CODE] Eye Adaptation

And if they are using a CRT or really old LCD then these coefficients will be the least of their issues.. contrasts, and general color representation will be entirely off no matter what one does.

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*sensei*
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Re: [HLSL CODE] Eye Adaptation

IMO a good CRT beats the crap out of a good LCD when it comes to color reproduction... I used to have an old professional EIZO CRT monitor (forgot which model), haven't seen anything do a better job at colors yet.

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*sensei*
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Joined: 07 Mar 2013, 10:14

Re: [HLSL CODE] Eye Adaptation

Well ofc. the above statement assumes consumer items... not weird experimental super over the top professional models that just about nobody uses...

In general if one is paying for an EIZO then one would assume the person knows why they pay that amount of money!
Also getting an EIZO then it does not really matter which you get.. just about all of them got perfect colors and god like contrasts only limited by the technology used.

Anyways I digress... this was not a thread about the silly EIZO stuff! :)

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Joined: 05 Jan 2016, 08:14

Re: [HLSL CODE] Eye Adaptation

I realize this is an old post, but could someone please help me out and implement the code Prod80 posted in the Fallout 3/New Vegas enbeffect.fx file? I've been tinkering with it and I just can't get it to work. Some help would be great!

Thanks!
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