Hi everyone, I have a request as someone starting with Blender. I have a little experience with 3D modeling but overall, I am new to this and I only tried Blender a few times.
I have never made a successfull render with caustics or glass surfaces. I looked at some previous posts in here and saw some excellent renders. I was wondering if someone could post a scene that is completely setup as a high resolution render that has glass surfaces, reflections and different colors in it. I would like to just be able to click the render button and see what cycles and Blender is capable of, without the intricacies of having to set everything up. Or if you know of any links to these kind of demo scenes, it would help. Render time does not matter but it would be nice if you mention it.
TL;DR: Use only mesh light (prefered low poly, ideally 1 triangle or quad), raise Integrator Min/Max Bounce to 12+, both general and transparent.
The problem is Cycles use Path tracer, it track photons only in backward direction, from camera to light sources. It work very nice if scene lit with only constant colored background, and you get all caustics, etc in reasonable time.
But that setup very rare, you need strong contrast light to get nice caustics (point, spot, small area lights), and here is problem. Path tracer cannot sample point light without Direct light trick, and that trick work very bad with glass (not work at all 
).
Long story short, use very low poly mesh (like single quad) with emission material, as light source, and raise Integrator MIN/MAX bounces both 8+, maybe more for multiple interreflection to avoid black zone in glass.
Cycles have no smart sampling like MLT, and caustics will be rendered with same priority as other scene parts, it take very long time to converge to nice strong smooth caustics.