William F Pokorny <ano### [at] anonymousorg> wrote:
> On 1/2/26 20:44, Kenneth wrote:
> >
> > However: Given two (or more) 'target' objects in a scene, the photon behavior
> > for each can be unexpectedly different, depending on whether 'count' vs.
> > 'spacing' is used:
> >
> > A) With 'count':
> > [snip]
> >
> > B) With 'spacing':
> > [snip]

>
> Re: (A) Interesting & news to me. I thought the count applied
> independently to each target. Thanks for digging into the behavior!
>

It was also a new discovery for me...as were Alain's comments when using
*multiple* lights and photon targets. In most of my old photon scenes, I used
'count' out of simplicity-- totally unaware of its various 'if/then/else'
results.

I'm beginning to think that 'count' should be deprecated going forward(!), since
'spacing' easily produces **expected** results, especially with the useful
numerical multiplier for a 'target'.

-------------
BTW (and a bit off-topic):
Just out of curiosity, I tried adding the typical no_shadow and no_image flags
to my photon 'target' object, to see what would happen...and either flag
*eliminated* the caustics on my 'collector' object's surface (in both v3.7 and
3.8). That does not *seem* to be an expected result to me-- based on what those
flags are usually supposed to do-- but I'm still trying to wrap my brain around
the logic it. IF those flags are operating correctly in this case, are photons
'shadow-based' in some way? That is, should photon caustics be regarded as
light/SHADOW effects?

But what definitely seems strange is that adding no_shadow to my *collector*
object eliminated the caustics too.  My understanding of
no_shadow is that it's only supposed to eliminate shadows that are cast *from*
an object (my collector in this case) onto other objects.

Whether or not this is the designed/expected behavior of the two flags when
photons are used, the practical result is that those objects will exhibit
unexpected absence-of-photon effects in a scene (given that 'collect ON' is the
default for all objects when a global photons block is present).  And the use of
no_shadow and no_image for scene 'workarounds' will not work without eliminating
the caustics as well.

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