I refer to the thread in povray.general - Future of missing "assume_gamma"
(http://news.povray.org/povray.general/thread/%3Cweb.5dbe6e69db426e49984b401a0%40news.povray.org%3E/).

I always rendered with gamm 1.0 from 1999 to 2005. Then I realized Gilles Tran
went back from gamma 1 to gamma 2.2 back in 2002 or 2003. Christoph Gerber
always used gamma 2.6 in his fantastic images (e.g.
http://hof.povray.org/River.html).

I know all the arguments for gamma 1.0 - but I like the sharper contrasts coming
with gamma 2.2.

Of course I tried several times to get the same effects with gamma 1.0, but most
of the times I used gamma 2.2 in the end.
Here I show an image of a display I saw in a mall, consisting of about 50*100
small tiltable plates (brushed aluminum I assume) showing some animated
patterns.

I tried hard to get a similar image with gamma 1, but no chance - it always
looked boring to me.

But perhaps I'm wrong - here is the source -

#version 3.7;

#declare RAD = 4;

global_settings {
        assumed_gamma 2.2
        max_trace_level 5
        noise_generator 2
        #if(RAD > 0)
                radiosity {
                        pretrace_start 0.08
                        pretrace_end 0.04/RAD
                        count 30*RAD
                        nearest_count min (20, RAD)
                        error_bound 2/RAD
                        low_error_factor 0.5
                        recursion_limit 1
                        gray_threshold 0
                        minimum_reuse 0.015
                        brightness 1
                        adc_bailout 0.005
                        normal on
                        media on
                }
        #end
}

#include "stdinc.inc"

camera {
        ultra_wide_angle
        location <21,-22.4,-28>
        look_at <30,16,0>
        right x*16/9
        angle 30
}

light_source {
        <0,0,-100000>
        color rgb 2.42
}

sky_sphere {
        pigment {
                average
                pigment_map {
                        [1      function {max (min (y, 1), 0)}
                                color_map {
                                        [0      rgb 2.35]
                                        [0.96   rgb 4.5]
                                        [1      rgb 13.5]
                                }
                        ]
                        [1      function {max (min (y, 1), 0)}
                                turbulence 0.2
                                color_map {
                                        [0      rgbt 1]
                                        [0.5    rgbt <0.385,0.77,1.1,1>]
                                }
                                rotate z*-45
                        ]
                }
        }
}

plane {
        z, 1
        pigment {color rgb 0}
        finish {reflection {0, 0.5}}
}

#macro RoundBox (A, B, Edge)

#local AA = <min (A.x,B.x),min (A.y,B.y),min (A.z,B.z)>;
#local BB = <max (A.x,B.x),max (A.y,B.y),max (A.z,B.z)>;
#local LBF = AA;
#local RBF = <BB.x,AA.y,AA.z>;
#local RBB = <BB.x,AA.y,BB.z>;
#local LBB = <AA.x,AA.y,BB.z>;
#local LTF = <AA.x,BB.y,AA.z>;
#local RTF = <BB.x,BB.y,AA.z>;
#local RTB = BB;
#local LTB = <AA.x,BB.y,BB.z>;

union {
        sphere {LBF, Edge}
        sphere {RBF, Edge}
        sphere {RBB, Edge}
        sphere {LBB, Edge}
        sphere {LTF, Edge}
        sphere {RTF, Edge}
        sphere {RTB, Edge}
        sphere {LTB, Edge}
        cylinder {LBF, RBF, Edge}
        cylinder {LBB, RBB, Edge}
        cylinder {LTB, RTB, Edge}
        cylinder {LTF, RTF, Edge}
        cylinder {LBF, LTF, Edge}
        cylinder {RBF, RTF, Edge}
        cylinder {RBB, RTB, Edge}
        cylinder {LBB, LTB, Edge}
        cylinder {LTB, LTF, Edge}
        cylinder {LBB, LBF, Edge}
        cylinder {RTB, RTF, Edge}
        cylinder {RBB, RBF, Edge}
        box {AA-Edge*x, BB+Edge*x}
        box {AA-Edge*y, BB+Edge*y}
        box {AA-Edge*z, BB+Edge*z}
}

#end

#declare metal =
texture {
        pigment {color rgb <1,0.98,0.96>}
        finish {
                diffuse 0.1
                specular 0.5
                metallic
                reflection 0.2
        }
        normal {
                wood
                scale 0.0005
                slope_map {
                        [0      <0.5, 1>]
                        [0.25   <1, 0>]
                        [0.5    <0.5, -1>]
                        [0.75   <0, 0>]
                        [1      <0.5, 1>]
                }
                accuracy 0.0001
        }
}

#declare metal2 =
texture {
        pigment {color rgb <1,0.98,0.96>}
        finish {
                diffuse 0.1
                specular 0.5
                metallic
                reflection 0.2
        }
        normal {
                wrinkles
                scale 0.01
                bump_size 0.1
                accuracy 0.0001
        }
}

#declare f_tilt =
function {
 pigment {
                waves
         translate <24,18,0>
        }
}

#declare s = seed (7);
#declare Tx = -110;
#declare Ty = -155;

#while (Ty < 110)
        #while (Tx < 155)
                union {
                        object {
                                RoundBox (<-0.44,-0.44,-0.44>, <0.44,0.44,0.44>,
0.04)
                                scale <1,1,0.05>
                                texture {metal}
                                rotate x*(f_tilt (Tx,Ty,0).x-0.5)*60
                                translate <Tx,Ty,0>+0.5
                        }
                        cylinder {
                                <-0.5,0,0.04>, <0.5,0,0.04>, 0.0125
                                texture {metal2}
                                translate <Tx,Ty,0>+0.5
                        }
                }
                #declare Tx = Tx+1;
        #end
        #declare Tx = 0;
        #declare Ty = Ty+1;
#end


Regards,
Norbert

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