> I've made a quick test with a scene :
>
> 1st render :
> pretrace_start 0.08
> pretrace_end 0.02
> error_bound 0.1
> low_error_factor 1
> always_sample off
> save_file "rad1.data"
>
> and 2nd render :
> pretrace_start 0.08
> pretrace_end 0.02
> error_bound 0.8
> low_error_factor .125
> always_sample off
> save_file "rad2.data"
>
> and rad1.data is 3 times bigger than rad2.data.. !

Ok, I think this is because in the 1st render, even with "always_sample off"
we can have new gather locations on the final trace, when povray don't find
*any* samples to reuse (For "always_sample on" we have more gathering if the
number of samples to reuse is < nearest_count). With an error_bound of 0.1
it's not surprising that it finds places with no samples to reuse, compared
to error_bound 0.8 for which it has probably at least 1 sample it can reuse
from pretrace and so don't need more gathering.

M

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