I know, this question sounds old, but there is a twist.
If you want to use image stacking to reduce noise, you have to choose a different seed for every render.
To do that automatically I found the following methods so far:
- using
#frameas driver in the seed field. This however only works if you have multiple frames (i.e. render an animation) - not for a single frame rendered repeatedly. - using the small Python snippet
noise.random() * 10000. This works fine for normal renders, but it screws up viewport rendering (at least in 2.71): the render never ends
Is there something, that can do both?
I've an "autosave" addon running. Let's say I've completed a render after an hour and decide that it looks nice, except more samples are needed. Instead of re-rendering with more samples, I hit "render" again with the same sample settings. This way the first wait was not in vain. However I forget to increase the seed value sometimes and have to abort the second render.
The Python snippet does exactly what I need, if it wouldn't make viewport rendering unusable.
– karamike Sep 12 '14 at 21:10