Just playing with glass caustics in BlendLuxCore v2.0alpha5. There's still noise in the darker bases of the glass objects after 3000 samples. I'm not sure if more samples would fix that, or if I just need to clean it up in post-processing.
Glass caustics
Re: Glass caustics
I like the caustics of the red thing the most (although the white vase creates a nice shape, too).
My guess is that those areas have many SDS paths (specular-diffuse-specular) which are notoriously difficult to render for most algorithms apart from SPPM/BidirVM. If the BidirVM engine in LuxCore ever leaves experimental stage you could try to re-render the image (or you can export to text files, edit the render.cfg file to change the engine type manually and render in LuxCoreUI).
You'll probably need postprocessing. Or you could try a border render of the noisy part to see if that cleans up in a reasonable time.
My guess is that those areas have many SDS paths (specular-diffuse-specular) which are notoriously difficult to render for most algorithms apart from SPPM/BidirVM. If the BidirVM engine in LuxCore ever leaves experimental stage you could try to re-render the image (or you can export to text files, edit the render.cfg file to change the engine type manually and render in LuxCoreUI).