> How fast does it render with Antialias=Off?

I just ran it again last night with no AA.  It took 6h 1m 6s.  If I
multiply that by 25 I get 6.27 days which sounds about right
for how long the posted image took to render.

> Just an educated guess, but i think the Antialias_Threshold
> value 0.0 is what's slowing down the render.

Yes, it is sending out 25 rays per pixel.  I'd expect the render
time to be linear with this value.

> POV-Ray skips the antialiasing step for a pixel if it determines
> that the pixel doesn't need antialiasing.  Setting the threshold to
> zero cripples this optimization.  I'm sure the default value of
> 0.3 will be more than adequate for this image.  This will allow
> you to set a higher Antialias_Depth without wasting time on
> pixels that don't need antialiasing--which, in your image, is the
> vast majority.

Well my problem was with how POV-Ray determines which
pixels didn't need AA.  With a threshold of 0.3 there were still
pixels along the red outline of the turret/cannon where the
test rays missed the thin red line and since AA wasn't
performed the pixel was rendered without any red.  This made
it look like there were breaks in the outline that I didn't like.
The grid in the far background also looked better with a
threshold of 0.  I agree aside from those two areas I could
have used the default 0.3.  The red outline is its own CSG
in my image.  Is there a way in POV-Ray to have the pixels
with rays that come near a particular object rendered with
different AA settings then the rest of the image?

> You can do that directly from POV-Ray by putting +fn in
> the toolbar command line, or putting Output_File_Type=N
> in the .INI file.

Thanks.  I'm still going through all the documentation and just
didn't know POV-Ray could do this.  When I downloaded
POV-Ray to be honest I didn't even know what PNG was.

> The documentation has a FAQ on this.  With the CJPEG
> program, i find that using the options
> -op -sample 1x1,1x1,1x1 -q 85 usually gives good results.
> The file ends up almost twice as big as with the default
> settings, but is still considerably smaller than the PNG
> version.

Thanks for point that out.  I just read that section of the FAQ
and I now know alot more about the jpeg format.  However
I've currently got Windows ME and I just did a search of my
system for cjpeg.* and nothing turned up.  I also went to a
DOS prompt and typed cjpeg and it tells me "bad command
or file name".  According to the FAQ I should have this file.
Is it named something else under Windows ME?

Thanks,
Carl

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