Issues Lighting a Light Bulb

[heolson]

Hi,
I'm posting this on behalf of my friend, who's working on our group project with me. We've both tried to sort out this issue to no avail. Here's her message:

I am relatively new to texturing and lighting. I have a scene in which there is a janitor's closet that is lit by a singular dangling light bulb. There is a shot that will have a close up on the light bulb being clicked off, as well as clicked on, so the textures and lighting needs to look accurate, even at close range. So far, I have followed along various tutorials to get the glass material for the bulb, and have tried various techniques, all without success. I have made the inside coil into a vrayMeshLight, but when rendered I am getting a weird disco effect that I don't know how to get rid of. I also tried using point lights and light linking to illuminate the bulb, with the coil set to full self-illumination, but haven't had any luck either at getting the glass itself to look well-lit. I am just not getting the glow that looks like the glass is being illuminated from the inside.

Attached is a photo of the kind of look I am trying to attain , and some renders that I have created and are obviously not achieving the effect I want.

Any guidance that can point me in the right direction would be much appreciated!

Caitlin

[Morbid Angel]

Well this is a tough one in terms of physical lighting. If you understand how the renderer splits out the lighting i.e. direct/indirect etc, then you will know that if your light has passed through the glass its no longer direct or indirect lighting, rather it has become a caustic. Since the light has gone through the refractive object and in terms of rendering any light that goes through the refraction comes out as caustic energy. Its not impossible to achieve this effect you are after with physical lighting but I am afraid you will have to use path tracing and its going to take very long for the image to resolve. The best and most practical method is to split the lighting out, render everything in passes and create final look in comp.