What type of glass should I use?
There are two refraction modes in Corona material, which should be used for rendering different kinds of glass:
- Thin - it does not refract light and does not cast refractive caustics, which makes it render very fast. This mode should be used for very thin or "hollow" objects such as glass panes in windows, soap bubbles, light bulbs.
- Thick - it generates refraction and should be used for solid objects such as vases, glass furniture, glass objects with absorption color, liquids. You can toggle refractive caustics for this mode, however enabling caustics will always slow rendering down.