I've followed the advice in the splotches pdf to try and get rid of the problems you can see in the attached image around the ceiling raft and on the column. I've set indirect caustics to none and visible to indirect rays un-checked for the ceiling material. I'm rendering using interior best but still having problems. Any suggestions? I've attached the dgn.
Microstation 08.11.09.459 Windows 8 pro
It almost looks like there may be some co planar interference, happening at the ceiling raft.
Regardless, assuming you are using area lights at that condition, you might try jacking up their shadow sampling.
If you don't have geometry interference or low shadow sample lighting, you could try creating an Insane setup, with higher indirect bounces and/or irradiance caching.
As i see your material "pain glow" light for ceiling have bump on ?
And ceiling have bump also - maybe it not necessary to have bump on celing ?
As Stonelli said you have "per light" shadows and they have "sharp" setting.
Try use Effects Manager, too
btw what i suggest is turn off Ambient, Flashbulb, Sky Dome ( render will be faster ) ,
change solar to phisically based,
add Environment Phisical sky (Main)or Sky Cylinder ( indirect ) and i think add glow to spot lights to make it visible
- it's my fast render with modified exterior good 1200 rays - 24 minutes
Within MicroStation 08.11.09.459 there is a new optio: Irradiance Smoothing. This setting is in the Global Illumination tree of Luxology Render Settings dialog, Advanced tab. When you bring up this value Splotches will be gone.
This is one where Effects Manager could help you balance the interior lighting with the exterior lighting. Also you should have indirect caustics on for refraction, if it is off the indirect sky lighting from the physical sky is not going to pass through your glass. The area light pointing up is noisy because you have it set to coarse shadows, you should make that soft very fine or better yet use a glow material in its place.
I would add translucent lenses or diffusers so that the spot lights and perimeter lights are visible in the render;-) You should also turn on the Auto Gamma Correct option on the Brightness tab of the Light Manager.
Thank you to everyone for the suggestions. I will do some more testing. For me the problem is always that I only get a chance to do renders irregularly so end up having to remember what I found out last time. I did try effects manager after posting this and it certainly helped with the lighting and saved a huge amount of render time.