In a neighboring topic, I began to study a way to simulate Swarovski crystals. The mechanism of light beam dispersion cannot be fully reproduced in SH3D, it can only be simulated. And the method of a Brightly lit billboard with a rainbow pattern is well suited for this. Here I told you about this method in more detail https://www.sweethome3d.com/support/forum/viewthread_thread,12818#60654 . The main idea is to place a very bright shield behind the viewer, illuminated by an invisible unidirectional panel (from the panel of new light tools.
I made a shield 1 meter high and 5 meters wide, surrounded it with a frame so that there was no illumination from the panel to the sides. I raised the whole structure to a height of 210 cm so that there would be no glare in the two glass cases on the far wall of the room.
In order for the effect of the billboard to act only on chandeliers, it is necessary to exclude shiny surfaces in areas of possible reflections, and assign a matte gloss everywhere in these places. In my case, the reflections should not be below 2 meters on the opposite wall (the viewer's eye level is set as 150 cm). I also analyzed the visual effect on photos of real chandeliers and realized that it is difficult to get a wow effect on a very light background, preferably a dark or even black background. Therefore, I lowered the power of all filling hemispherical light towers to 1% (there were 2% each). And I increased the brightness of the render a little. The ceiling darkened a little, the colors became a little brighter. In general, the experiment resulted in an imitation of rainbow highlights on crystals. I can't say it's wow, but it's not just plain gray glass anymore. You can use it sometimes if you want variety. By the way, I assigned the panel power to 100%, so that I could be sure. The drawing can be selected and changed, in some places my reflections are too wide and flat. And of course, on low-quality trial renderers, you have to try to find the right options, although you won't be able to understand the fine lines.
