face count and render times with Mesh Lights?

[zmurdz]

Hi,

I need some help - I am using mesh objects as light emitters (object tab -> "Light"). There are quite a lot of them So I am facing huge render times.
What I don't fully understand is if the face count of the emitting object has any impact on render times or is just the count of the emitting objects?
Is a light emitting plane with one polygon faster to render than a bulb modeled with 416 faces? The bulbs are visible in the scene so I can't simply replace them with a plane. What can you suggest for optimizing render times in such case?

[bdancer]

Re: face count and render times with Mesh Lights?

The bulbs are visible in the scene so I can't simply replace them with a plane. What can you suggest for optimizing render times in such case?

Use Light material on a bulb with low emitting settings (for fake), then place lamp inside bulb (with appropriate radius; without Radius light will be of Omni type which is not good for GI) and exclude bulb from this light.

[zmurdz]

Re: face count and render times with Mesh Lights?

I'll try this tomorrow, thanks!
Doest that mean that every poly in the mesh light causes additional sampling of the light and slows down rendering? Or the reason is that the mesh lights act as Area lamps, which are generally slower? If I do what you suggest I will not lower the number of lights, but just change their type (to point lights). I'd really like to understand the logic behind this

[bdancer]

Re: face count and render times with Mesh Lights?

I'd like to understand the logic behind this

I'm not a V-Ray developer =) Contact Chaos Group for more info.

[zmurdz]

Re: face count and render times with Mesh Lights?

you definitely know more than me!
The strange thing is I couldn't find any specific info on this topic in the internet, and I searched a lot before posting here
Maybe it is a good idea to ask the devs from ChaosGroup, really