Unfortunately, this isn't an ideal scene for photons.  You'll probably end
up having to set some of the settings manually, specifically the "radius",
the spacing, and possibly the expand_thresholds.  Normally, POV computes
these autmomatically.  However, some scenes that have very disparate photon
densities can confuse these automated algorithms (which are fairly
primative, I admit).

Some things to try:

1) Start by greatly increasing the number of photons in your scene.  The
white dots that you see are individual photons, and each photon is carrying
a LOT of energy.  For good results, you'll probably need at least ten times
as many photons.

2) Use the "multiplier" option for the "radius" setting.  Here's an example:
photons
{
  ...
  radius /*first parameter is optional*/, 5
  ...
}
This will tell POV to take it's auto-guessed gather radius and multiply it
by five.  If that doesn't smooth out the photons, try multiplying by ten.

3) Try specifying the spacing (as opposed to "count") and the exact gather
radius.  Example:
photons
{
  spacing 0.1
  radius 0.05
}
Note that the proper values for spacing and radius will depend on your scene
size.  Spacing will be close to the average space between photons deposited
on the surface.  Note that usually a good radius:spacing ratio is 5:1.

BTW, the "Photons FAQ" section of the documentation specifically addresses
this problem.

-Nathan



"dan B hentschel" <dan### [at] alumritedu> wrote...
> This is the image that pertains to my question on photon usage in
> povray.newusers. I know. It's pretty ugly. It's obvious I am using photons
> incredibly wrong. I need some suggestions on how to begin. Please excuse
my
> ignorance. Also excuse the extreme low quality of this render.
>


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