I am clueless on how to light a room.

[Kanephan]

I’m slowly modeling the entire computer room that I am presently in. The models are coming along, but I have no idea how to light it correctly. Everything I try results in harsh shadows, flat lighting, or crazy blown out highlights (especially on the walls, when everything else is lit at an acceptable level).

Basically the problem is that most tutorials I come across tell you how to light a subject, but not how to realistically light an entire room. I want to replicate the incandesant lights on the ceiling, not lighting from a window (though I might choose to try that later too).

So can someone give me some guidelines? Should I be using spots? hemis? lamps? How do you go about using three point lighting in a whole room?

Id appreciate if someone could point me in the direction of a tutorial that gives a very good tutorial on how to light a room completely, or just give me some tips. I know trying to replicate the placement of the real life lights won’t work properly, but beyond that I’m sort of clueless as to what kinds of lights to use, at what distance and energy, and all that.

Lastly, I’m trying to avoid Radiosity as it is still a little out of my skill level.

Thanks!

[toontje]

Hello, may I suggest that you buy "Digital Lighting and rendering? Every page is a revelation.

And it has a whole chapter dedicated to rendering rooms and such.

OK, basically and quick and dirty you should follow these guidelines (it may seem like cheating because it is, and it is the way to do, even at Pixar etc.):
NEVER use ambient light. It will give you flat shading and shrink you tone range.

Materials:

Keep the color of the RGB values between 0.2 and 0.8.
Don’t exagerate specular highlights. If I’m not mistaken even highly glossy plastic has a shinyness of about 40%. Reserve specular highlight for metals mostly.

If you notice banding on your surfaces, try giving them a very light noisy bump map.

Lighting:
You clearly stated that you don’t want outdoor light to illuminate you scene. There is a lot of room for artistic freedom here. Such scenes could be lit with spots only. They’re very flexible.

You could construct your light rig in these 4 steps.

First, give some thought to color balance. So use a slightly yellowish tint for your main lamp (if it is tungsten). Your main lamp could be a could be a standard that doesn’t cast shadows. Use linear decay, if after the test render it looks too bright, try quadratic decay. Test your render and see if this is the overall light intensity you are hoping for, but only a little darker, I’ll explain later.

Now it is time to simulate a little Ambient Occlusion (I know that you can let Blender do AO for you, but I’m all for flexibility and artistic freedom). What you should do is to
use negative spot lights to ‘suck’ the light out of the corners of the room and places where you expect to have little illumination. Don’t exaggerate, it is a subtle effect, but make it look like AO-ish.

Now it is time for bounce lights. This is fun, because if you do this just right, your scene will look like it is rendered with radiosity/ GI. Basically, just imagine your the light of your lamp hitting a surface and bouncing off a nearby object (wall, floor table etc). Where the light bounces, place a lamp (NO SPECULAR) with the color of the object it bounced of. Again, this is a very subtle effect, so make sure that it is a quadratic decay, no specular faint lamp. I would place about 6 bounce lights, maybe 8 tops.

Finaly: SHADOWS…
The reason I suggest to split the lights from the shadows is that you have more room to tweak those independently. For shadows you should use spot of course. Shadows may be sharp or soft. As a look around in my own house I see mostly soft shadows.
Now, is your room almost empty? Or does it looks like Andy’s room from Toy Story?
The reason I ask this is because if you just have a few objects in your room, you could place shadow casting only spots directly above those objects. But if you room is really full, duplivert a shadow casting only spot on half a icospehere and place it at the lamps location. Make the spots very wide. Make them soft or sharp … whatever floats your boat.

I’m assuming that you already know that you have to model the lightbulb itself and give it a emmit value.

I hope you are not intimidated by this, because this is a standard method. But it is fun

If you really want mind blowing stuff, render it with Yafray full GI and be prepared to wait a long time before the rendering is done.

Hope I was of any help

[Kanephan]

Well here’s what I have so far…

That’s not too bad, but some shadows are harsher than I’d like. I read your suggestion, but theres lots of terms Im not familiar wtih. For example, Ambient Occlusion. I’ve seen the option but I don’t know what it means or what it is for.

[IanC]

For realism, you need to have light bouncing off of objects.

You can do this in blender internal with radiosity (not really recommended unless you are working on a game). Or you can fake it with lamps (best for speed, great for animations, but not very realistic).

Or, you can use another renderer. Either Yafray (easiest to use with blender as it is integrated), or indigo are excellent choices. Indigo is unbiased so will converge on a very realistic result, but can be a lot slower and wont necessarily look better.

An important thing to remember that accurate != good picture.

[Kanephan]

I’m trying to use Yafray but I can’t figure out how to work it. The only semi-succesful render I’ve had was completely black with only teh compute rmonitor screens showing.

I realize this is because those surfaces are emitting light, but what happened to my real lights?

And will YaFray’s GI skydome work if I have a ceiling on my room model?

[Kanephan]

Finally got a decent result, though its mighty dirty looking. I dont know if that means I should increase photon radius or…?