Rendering times

So with the first set close to completion, I wanted to start setting up the lighting for the scene to increase the believability of the textures and overall aesthetic of the scene. I started with a physical sun and sky which is my go to lighting system due to the accuracy of the render. Here is a frame:

Although this was a very appealing render with all the materials working the way I wanted them too such as the cupboards adopting the specularity I input into the texture node with a home-made specularity map but unfortunately the render took a whopping 39 minutes to complete. and although I have some fairly expensive materials I was hoping to get the render time down to about 5 minutes. This was going to be hard.

I decided to try different lighting.

I got rid of the physical sun and sky and created some point lights underneath the light shades.

With a much more tacky render it still didn't decrease the render time enough for me to settle.

I was then picking the brains of one of my tutors to see how to tackle this problem. He suggested that I try rendering it in passes, using an ambient occlusion pass:

Then to render a diffuse pass using Maya software:

Then combining the two to get the desired look.

This would help apply the same soft shadows as a mental ray render with hopefully shorter render times. Although the Maya software render didn't take as long, the combined render time for both passes was exactly the same as a mental ray render with nowhere near the accuracy that I wanted.

But this wasn't too important as I was intending to focus on the animation and story than the quality of the render ... but I'm a perfectionist. But also someone pointed out a very good point, if its daytime, why would they have the lights on? this was very true, the only problem was that the scene wasn't lighting completely so the characters were way too dark. So I decided that I should cut a couple of window holes in the side and stick with the mental ray physical sun and sky, this might also reduce render times or possible artefacts due to the lighting protons.