I would like to know how you get the feel of darkness in all room while still being able to see some detail.Three of my rooms need to be dark but show the detail of the furniture some and the empty room needs to be completely dark.
It's called lighting.... you need to statr experimenting with lights in your scene. There's no hard and fast way of doing it so you just need to have a go. I warn you it may not be easy. You will need to use things like decay to get nice falloffs from your light to leave areas of darkness. But remember that in CG if there is no light then it will be pure black. In an environment such as yours there will never be anywhere that is completley black. There's always some light. But dont use ambient lights, they will flatten out your lighting.
I suggest you start with no lights and turn off the "use default light" in the render globals. Then using the maya software renderer start to add lights one at a time. All you need are spotlights (with penumbra falloff) and a few point lights. Dont worry about rayracing or reflections or anything like that for now. Get the basics of lighting down. Then you can worry more about the more advanced techniques such as HDRI lighting. Don't run before you can walk. I would forget about the outside for now. If you only have to worry about the windows (plus it's stormy outside) you can do it with a photo or simple geometry. It's the least of your worries right now!! 
Whats' the main focus of the project? modelling? lighting? realism?
Alan
Technical Director - Framestore
Currently working on: Your Highness
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