radiosity help

[dnagi]

Hello all,

 

I am curious if any one has some suggestions. I have started working with radiosity. I have a sun casting light into the room at 7000 lx. I have my radiosity intitial quality at 35%, refine interations at 2, inderect and direct at 3 and 2. I also have the logarithmic exposure control on. The brightness is at 80, contrast at 60, and midtones at 1, and physcial scale at 1500. I do not trully understand the logarithmic exposure controls. Is using radiosity a trial by error process. I am looking into an assortment of text for help but everything is brushed over lightly. I am slo using the scanline render. Any comments or suggestions. Is it also possible to use the light painting tool after my geometry has subdivided. looking for answers

Dominic

[Tim Saunders]

Are you using Viz or Max?

[dnagi]

I am using max...I have placed an array of photometric spots since the last render. I will place them in the morning online for everyone to see. I have additional issues with the renderings, but looking forward to the finished product. Thanks for any and all suggestions. Oh yes, Max 8.

[dnagi]

I still need to fix alot of the geometry. I have many issues that need to be taken care of. I have reflectivity issues off the floor. Alot of my geometry is open as well. I would like to place a scene out the window. Should I drop[ a map on a plane to fake it? or something else. I am also having issues with the modeled backsplash behind the sink. It appears black. I am not sure why. The tiles are actually modeled and textured mapped the same color as the wall. I would love any and all suggestions. I still need to boolean holes for the can lighting on the ceiling. Thanks again

 

dom

[dnagi]

anyone?

[dnagi]

can anyone help me with why the backsplash is rendering black? I would really appreciate it.

[Brian Smith]

There could be numerous things wrong. First of all, you shouldn't have to play around with the logarithmic exposure control much (+/- 10 on the brightness maybe), and it is not the heart of the problems. Make sure that your Global Subdivision Settings are set to break up the mesh into small enough increments (default settings should do OK for starters). Try 30% initial quality solution and at least 60% for production. I would set refine iterations to 10 (no more than 20) and Indirect Light Filterings to 10 (both of which will smooth out the variations in GI that look like splotches). That's all you should need to play around with at a basic level and will provide decent results. The other part of the equation is the photometric lighting you're using. You might want to play around with Standard lights to work out the Radiosity problems and then switch over to photometric when you like the results. The attenuation seems to be a problem in your scene which is harder to manage with photometric lights. Also, if you want to use photometric, make sure your scene is to correct scale because photometric lights are physically based and attenuation is automatic with them. I would also try working with one light in one area of your scene, get that one area looking good and then add more lights at adjust the others as necessary. Hope this helps.

[Neelu]

can anyone help me with why the backsplash is rendering black? I would really appreciate it.

 

 

I agree with Brian Smith.

I think the logarithmic exposure controls are too bright and there's too much contrast.

 

Work with Photometric lights and Architectural materials when using radiosity.

Standard lights just don't do well sometimes.

 

Why did you apply a texture to the tiles in the backsplash? I would make it a flat color without loading a bitmap. Make sure that backsplash geometry is modeled cleanly.

 

Also, apply an Advanced lighting Override material on the backsplash and increase the reflectance. The same settings are in Architectural material as well. Radiosity treats dark colors with very low reflectance, so make sure you increase that.