Different results of rendering glass

[rbryll]

Hi,

I spent a little time testing different render settings when rendering realistic glass material. I attach images obtained using easy settings 07 (High+), 08 (Exterior daytime) and 10 (interior +). The scene was not modified in any way between the renders; the sun was the only light source and the glass was Realistic glass--> common with alpha of 0.2. I'd like to ask a few questions about these results:

1. Is the lack of caustic in the Easy 08 image a bug or a feature?
2. Which one of these three render settings should be considered closest to physical reality (or rather the most physically accurate simulation of reality)? I've always assumed that the iterative methods (08, 10) are most "photorealistic", but looking at these results I'm no longer sure. There's clearly a big difference in refraction/reflection on the bottom of the glass between setting 07 and both iterative settings. Actually, I would intuitively choose setting 07 (High+) as closest to "reality" (the bottom of the glass is bright and the light table surface refracts through it), but obviously my gut feeling may be completely wring - maybe there's total internal reflection and the bottom should become very dark as in settings 08 and 10.

I would apppreciate any comments/advice.

By the way, the performance/price ratio of this renderer seems huge (this is a barely-informed opinion of a total beginner)!

Thanks a lot!

Robert

[Chris]

Hi Robert,

First, regarding the Exterior preset, it's optimized primarily for, literally, exterior images where you aren't going to be as interested in caustics. Instead, you get a faster render with good shadows and lighting (when used with only sun and sky).

High+ is going to give you the best representation using 'biased' methods, so you should get good results. However, Interior+ is definitely the most accurate and realistic. Personally, I think your third image, Interior+, does actually look the most realistic. Maybe it's a little too dark, but a better representation overall than High+.