Hi Forum!
I have a conference hall with a lot of spotlights (both white and coloured). Could someone advice me how to speed up renders (settings in lights and/or render settings). Many thanks 
John.
Hi John, Generally, the default settings are the best. That’s how we have optimized Corona. Can you tell me more about your render times? What kind of times are we talking about here? What are your sector light settings? Is directionality being used at all? Feel free to share any images if you can.
You can make your spotlights only directly visible (not emitting any actual light) and then add a single big invisible light emitter under them. Of course it depends how realistic you need your scene to be.