Help rendering interior scene with natural light

[GeorgeAngelov]

Hi all,

I need a bit of a help rendering an interior scene with somehow natural light.

Basically I have a living room (a real one) and I want to paint the walls. I want to play with the colors inside max so I can get a sense of how it will look like, so I know what to buy.

For the past 3 days I've been struggling a lot so I started fresh now. However I still need a help.

I am using Max 2017 + Mental ray.

This is what I have setup right now:

 - Basic poly living room model + windows (without glass) + wall heaters

 - Everything has MR materials

 - Daylight System

 - MR Sky Portals on each window

The biggest problem is that I cannot get enough light to the back of the room.

Current settings are:

 - FG with 5 bounces

 - Photo Mapping

- GI

 -  ~4.0 Sky param, ~1.0 Sun param, ~3.0 for each Sky Portal

Those are the settings for the attached render.

I haven't tweaked Exposure as it will blow off the windows.

I have one main question for a start - how to get rid of those Sky Portal hotspots around the windows? 

I either get dark room, or get Overexposed windows or I get somehow even light but with huge bluish tint ...

[Francisco_Penaloza]

Your 'problem' is a natural phenomenon. If you take a photo of your room on a sunny day you'll see that the exterior is very bright /blow out/ and the interior look well.  Not if you adjust the camera exposure to show the exterior correctly then the interior will look dark. and this is OK this a real phenomenon. it's something that Professional photographers have to deal with too.

In your case you need to first place some lights inside your house, then adjust your exposure controls. there is aburn value in the exposure control that will help you to reduce that 'burn' from the portal sky.

Now you are getting a lot of that because you are increasing the default intensity.

Since this is a 3D software you can do some cheat. if you go to the portal sky then you have an opacity value if you change that value anything that is behind will look darker. in your case, you'll see your windows less blow out.

so your rule of thumb should be, place lights just as real life, with the correct intensity, then adjust exposure and color mapping. then if necessary place more lights inside to compensate for the intensity of the sun, then you can adjust the portal sky transparency.

Best luck.