Bob heeft geschreven in bericht <376B02A7.DAE1FD19@aol.com>...
>I'm always using a typical assumed_gamma 2.2 and display_gamma 2.2, both the
same for
>almost every image I render with few exceptions and they print fairly well as
is on my
>Epson Stylus Color. I sometimes brighten or darken them no more than a few
percent in
>post-processing (Paint Shop Pro or Picture Publisher). Meaning I seldom need
much
>change. ....

Investigated it a bit more. Did a serie of renderings with assumed_gamma from 1
to 3 and printed them on transparent sheets. Dusted off my old densitometer and
measured the scales. The one with gamma 2.2 is perfectly linear, 50% gray is 50%
gray. Then had a look at the rgb values in the files with PSP and the hex tool
in XnView. Only the 2.2 scale is linear.
So with an assumed_gamma of 2.2 and display_gamma 2.2, POV-Ray does no gamma
correction (the same result as when you set no assumed_gamma at all). And the
printer I use (epson 440) has no influence on the gamma of the print.
Finally I took the grayscale in the darkroom and made a photoprint of it. Looks
good.



Lance Birch heeft geschreven in bericht <376b0567@news.povray.org>...
>......

>The ultimate is to get it imageset and then printed as CMYK plates... but
>that would cost a small fortune and is only really good for large runs.
>

The real ulitimate high end print would be a Fresson print. The problem is there
are only two suppliers in the world and they are very selective in the artwork
they print. And only one of them does color work. Doing it yourself is
impossible.

A simple straight forward way, with very good durability, would be printing to
slides and make ciba-crome prints (use the low contrast material).

There are other high quality processes like the ful color carbo print and the
gum print (the one I going for at the moment). Both are photographic processes.

ingo

--
Met dank aan de muze met het glazen oog.

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