Vray lights intersecting with scene geometry?

[philvanderloo]

I was told by a support person at chaos that a scene I sent over had 3 Vray lights that "intersect with scene geometry, and could cause a little slower render times and add noise."

 

Not wanting to keep bugging this person with nagging questions, I wondered if someone could elaborate a little on what I might be looking for. This makes no sense to me but I'm sure this is valid info. He was referring to the 3 recessed can lights in the kitchen ceiling.

Thank You

[Scott Schroeder]

I think he might be referring to putting the light inside the recessed light, which is indeed a horrible practice. The light should always sit just below the fixture and cast light into a scene. By shoving it up in the fixture, you now have an added level of shadows that need to be calculated and less rays of light being shot into a scene as well as rays that are being bounced into oblivion and make come back as light leaks. If you need specific light shape being cast, use IES profiles. For the most part, the look of the most average recessed light can be easily achieved with a standard max spot and adjust the hotspot/falloff values.

 

Think of putting a black piece of paper with a hole punched in it over a flash light. Now take the paper off. Which version of the flashlight do you think is going to illuminate the scene better.

[Corey Beaulieu]

Generally, I think they simply meant that you want to avoid co-planar events between lights and geometry. Just grab the lights and pull them down to be just below the light fixtures geometry.

 

Light co-planar geometry, the light and the surface battle over which one is showing and can create a slot of noise.

 

Sorry Scott. I think we were typing at the same time.

Edited July 31, 2014 by CoreyMBeaulieu

[philvanderloo]

Thank You for the replies.

I thought that I might try creating a sphere and squashing it down almost flat. Then creating a vray mesh light using the sphere and place it just below the recessed cans.

Would this be a good alternative?

Edited August 1, 2014 by philvanderloo

[Nicolai Bongard]

The mesh light/squashed sphere will look kinda funky, since it will send out the same amount of light in all directions, you might end up with the areas of the ceiling around the lights being very much illuminated but not much light going where it is supposed to go, namely down and into the room in general, if that is your only light source per lamp. What you want with recessed ceiling lamps is to spread light out and into the room usually. If they are close to a wall you might also want a certain spread of the light to paint the wall surface, that is where ies profiles come in handy. Usually you could just stick to a IES light pointing downwards and make the texture of the inside of the light a vray light material so that it appears to be illuminated.

[Ismael]

http://www.erco.com/~klickmeister/km_ls_download/ls_download.pl?aktion=_startseite&sprache=en&dir=40_planning_luminaire/63_max

 

Edit:

 

http://docs.autodesk.com/3DSMAX/16/ENU/3ds-Max-Help/index.html?url=files/GUID-F5E89444-F098-43FE-BD02-90A0E3B856BF.htm,topicNumber=d30e76524

Edited August 4, 2014 by Ismael
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