Lighting Issues

[schroeder]

Hey Everyone,

I'm working on an airport project at the moment, and am trying to work out the interior lighting. The image below was rendered with only a VraySun, and uses the physical camera. There are light posts visible in the image that run from the foreground to the background with 4 Vraylights each. Each light is using Radiant Power as the lighting units and has a strength of 80 units (Watts).

In the image below, the lights have been turned off for the sake of render speed, and the lighting is coming entirely from the vraysun is being dispersed by the roof membrane material. As you can see by the framestamp, it renders in 1.5 minutes. The issue comes when I turn on the lights in the lightposts; the rendertime suddenly shoots up to 53 minutes!

So I'm wondering what I can do to get that time down (need to produce an animation ultimately). The important points I need to consider are that the roof membrane is semi translucent, and that the animation will travel from outside the building to inside the building.

The image:


Thanks for your ideas,

Andrew

[Morbid Angel]

this is normal. when you have a lot of lights in the scene, they will take long time. What happens is, vraylight doesnt have a termination point. So it shines forever, though it may appear decayed it will still be taken into the account. I would say that in such situation as yours, precalculating the irmap with lights on against the simple vray mat for the entire animation, then using that for your render may help. Other then that...you may use standart max lights with termination point.

[Dynedain]

If you are going to move from the outside to inside, you need to have different lighting outside (much much brighter) and you need to adjust the exposure as you move indoors (just like a real camera would have to do).

[schroeder]

Thanks Morbid, I totally wouldn't have figured out that the vraylights didn't terminate. That managed to get the render times from 53min to 5min.

New Image:

[Morbid Angel]

glad I could help a fellow canadian

[Da_elf]

whoo hooo. go cana..... ops. forgot i left canada to move back to barbados hehehe

[MegaPixel]

schroeder,

What type of lights did you end up using for your light posts instead of Vray lights?

[schroeder]

Ended up going with standard max spotlights. Here's another image with another.... 50ish lights in it.

[Morbid Angel]

i would say that if you are going for more realistic setup, adding some area shadows on those spot lights would help a bit. Usually a spot light inparticularly ones like you got in the scene would cast a very inprecise and scattered shadow. Keep that inmind. However having said that, adding area shadows will dramatically slow the render time. So be careful.

[Penry]

Geometry

The one thing that has helped me reduce render time greatly is to attach all similar geometry together forming one object with a single multi/sub-object material and producing proxies for multiple instanced geometry.

Other than that...go out and but a render farm! if you can afford it.

[Penry]

typo

that's buy a render farm........not turn into a goat and grow horns!!!

[schroeder]

Hey guys,

Thanks for the ideas on the area shadows. I gave it a shot and figure the time/difference balance wasn't worth it in the end.

As for the render farm idea, it's not such as a bad one... we're picking up another dual 5150 xeon system with 4GB of ram which should take care of a huge chunk of the animation.

Some updates:


Elevations:

[marcdevon]

One word. Beautiful. Your client should be very happy. Keep up the good work.

Marc

[schroeder]

Thanks for the compliment Marc. What the hell, I never really share our work:

Another frame from the final animation (exterior portion)

[Dynedain]

You're doing an animation with all this stuff in it and you aren't using a render farm?

You're crazy!!!


But it's looking good. One thing that really really helps with this kind of thing is not having one long camera path. Instead, break it up and think about it from an editing standpoint. ie. If someone was going to make a documentary film about this project after it was built, they would never just walk around it in one long camera path. They'd setup a lot of different shots, and do what they needed for those shots. Same thing with CG... instead of one long camera with a lot of complications caused by the scene being too big, or too many interfering lights, etc, etc, setup a massing scene to prepare your shots. Then detail each shot in an individual scene. This way you can adjust lighting, cameras, textures, whatever you need to make each shot work.