I'm trying to create a basic animation of a building that I've modeled, but I'm having a few problems with the final gather solution.
With Read/Write file enabled and as the animation progresses artifacts begin to appear and continually get worse. The first frame looks fine, but by the final frame the animation looks terrible. Strangely, if I render the final frame without Read/Write file enabled, the result is good.
I was hoping to create a final gather map and then freeze it before rendering the final animation to avoid flickering and improve the render time (I don't have a very power full machine for rendering, just a laptop).
I have included some images below so you can see for yourself. The first image is the 1st frame of the animation. The 2nd image is the final frame of the animation with read/write file enable (the one with the artifacts). And the final image is the last frame of the animation rendered with read/write file disabled.
The scene is simply lit by a MR sun and MR sky with logarithmic exposure control enabled.
The final gather settings are as follows
FG Point density 3.0
Rays per FG point 1400
Interpolate over number of FG points 6 (I know this is pretty low, but if I have it any higher the weather boards start to look flat)