POV-Ray : Newsgroups : povray.binaries.images : IsoStones : Re: IsoStones Server Time
8 Aug 2024 12:26:44 EDT (-0400)
  Re: IsoStones  
From: PM 2Ring
Date: 18 Sep 2005 11:20:00
Message: <web.432d849281952861093c2050@news.povray.org>
"William Pokorny" <pok### [at] attglobalnet> wrote:
> As someone else said your IsoStones are very instructive - thanks for
> posting the source.

Thanks, William.

> The stone textures - in fact most of the old 3.1 textures - have never been
> updated to account for the resulting image being gamma corrected. The 3.1
> stone textures for example were to be rendered with an assumed gamma of 2.2.
> The automatic portfolio set up INGO put together rendered them with an
> assumed gamma of 1.0 just as you too used them. However, used in this way
> all these textures will appear washed out compared to the creators intent.

Ok.

> For good reasons we should be using the assumed gamma of 1.0 for renders,
> but the majority of the sample textures look washed out if you do it. Leads
> to some confusion I think - it certainly confused me for a time.

Me, too! I'm still easily confused about how assumed_gamma & display_gamma
work together. :)

> A_stones.jpg  is my render of your original source using 3.6.
>
> B_stones.jpg uses the assumed gamma of 2.2 so the stones look as they did in
> 3.1, but naturally the sand and lighting is darker than you intended because
> no gamma correction was done - my display gamma is set to 2.2 as is true for
> most PC users (1).
>
> C_stones.jpg takes a stab at un-gamma correcting the stone textures so that
> when the gamma correction is done the stones appear as I think intended by
> the texture creators, but with your lighting and sand color.
>
> (1) - Most all PC displays have a display gamma of about 2.2 except for
> Apple, SGI and perhaps a few other less common platforms.

This old monitor is very bright. I have the brightness as low as it can go,
but it's still a bit too bright for me. I have set my Display_Gamma to 2.6,
but I think I should re-calibrate it. All my images look too bright on
other peoples' monitors & my lcd monitor at work.

At first, this didn't worry me, as I've seen some fantastic pictures here
that were using gamma 2.2 that were so dark I had to gamma-correct them to
view them. Fortunately, my video card lets me do this pretty easily.

Your picture C looks too dark to me, B is just right. As I said, I've got to
do something about this monitor. :)


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