Realistic Lighting is Hard… right?

I’m mostly concerned with realism in 3D. Making a rendering that people think is a photograph is a goal that makes things harder than they probably should be. While some may say that materials create realism, my vote is that lighting makes a bigger difference.

I’ll start out by saying that I am a V-Ray biggot. Finding a good lighting mechanism for realism has made me feel pretty let down by 3ds Max’s built in lights. My philosophy with regard to scenes is to use as few lights as possible, and obviously as few polys as possible as well. I have contemporaries that fill scenes with lots of lights, all kinds of lights, in an effort to make a scene lit properly. Even after I introduce them to Photometric lights, they can’t break the habit.

I’ve had the best results with an HDRI environment and a single, well placed and sized, V-Ray light. To start, here is a porcelain teapot with nothing but default lighting:

Fast, but completely unreal. Using VRayShadow, a Target Spot is placed over the teapot:

Well, not really show-stopping, is it. I personally only add individual lights to a scene once all other V-Ray::Environment lighting is found to not work. Lets start over, this time creating a few materials we’ll need:


The teapot material is shown, and the other 3 are pretty basic. The top material is a simple V-Ray material with a checker diffuse, the 3rd is an HDRI map, and the last is a V-Ray pure reflective material (like a mirror).

Next, place 2 V-Ray spheres around the teapot. Apply the mirror material to them. The checker pattern is for a V-Ray plane-the surface the teapot is resting on. as for the HDRI map, drag it over to the V-Ray::Environment panel for GI Environment (skylight) override and Reflection/refraction environment override as shown:


Notice that we’ve turned on V-Ray::Indirect illumination (GI). If we override 3ds Max’s default lighting as we did with the HDRI image and don’t check that option, this is what our sene will look like:


But with it checked, the result is very different:


Now that is pretty damn impressive for having no lights whatsoever in our scene!

But if I had to add a light, in many (not all, unfortunately) cases a V-Ray light is best. Why not all? Because the light itself can’t be made invisible (like you can with some of the 3ds Max stock lights). But to really show off the lighting effects, we really should change the color of our teapot. I’ve changed our pure white material to a diffuse of 172, 57, 57 and added a v-ray light directly above the teapot (length & width the same as the teapot), and a multiplier of 10:


Just adding that light increased our render time by 208%. Another great reason to always try to light your scenes without lights-even v-ray lights. You can see the shadow the light is casting under the light, just as it would with a ceiling light in the room.

Can you see the problem with the v-ray light I mentioned? Take a look in the reflections for a white square-that is our light, which is up and out of camera view. I really, really wish that visibility could be toggled.

So the results would indicate that to create realistic lighting with short renders, first try to use just HDRI.

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