Well- it seems that Indigo really doesn't like caustics.

It wouldn't render right (overexposure b/c of small area light- and overall very weak skylight) with Bidirectional Path Tracing (which is almost ok with caustics), so I had to just use Path Tracing with it.

Whoo- bad, bad, bad.

This scene is only 3 spheres and 2 triangles. I estimate that at least 10,000+ mutations per pixel are enough for this scene, (for noiseless) and, as you saw, 2300 mpp was barely enough for a pure lambertian scene- with only diffuse interreflections (Global illumination).

And-by the way- Indigo is about the same (rendering technique wise) as Maxwell- just that Maxwell gets the job done in about 1/10'th the time :p

Output:
Done 1254579500.000000 mutations (2613.707292 mutations per pixel)
Time elapsed: 3h, 14m, 16s
Mutations per second: 107629.376597
saving tone-mapped image to png...
done.


No PostProcess in Photoshop


W/ PostProcess