Am 16.08.2011 21:00, schrieb Zeycus:
> I have a problem: I want to use sky_sphere to make a sky, but for some reason it
> does not change color smoothly, you can cleary see lines that separate different
> "regions". I played with Antialias_Threshold, thinking that is the key, but
> whatever I do I keep having this ploblem.

That's your graphics hardware and/or image file format limitations you see.

If by "clearly" you mean "when zooming into the picture" or "when having 
an exceptionally close look", then that's perfectly normal for the 
traditional 8 bit per channel (24 or 32 bit per pixel) file formats and 
graphics cards. Yes, depending on the sky sphere gradient they can be 
quite prominent, even to the point where "clearly" would be a fitting term.

In that case...

(A) If you're using POV-Ray 3.6, output the image to a 16 bits per 
channel file format (e.g. "+fn16" for PNG with 16 bpc), then downsample 
to 8 bits per channel using some external piece of software that 
supports dithering (e.g. LILYsoft's IC, 
http://www.lilysoft.org/IC/ic_index.htm).

(B) If you're already using version 3.7(RC3) of POV-Ray, use "+th" or 
"Dither=yes"; this activates POV-Ray 3.7's inbuilt dithering for the 
output file.

"Dithering" is a mechanism that hides color banding artifacts by adding 
noise-like artifacts, which are less obvious to the human eye.


If by "clearly" you mean "at first glance", then you may indeed have set 
your display to 15 or 16 bits per pixel (i.e. 5 to 6 bits per color 
channel); in that case I suggest you simply change that.

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