Photorealistic Global Illumination in max5

[RPG2006]

In reply, to get a good GI or Radiosity render, you should expect to have to wait.

10 minutes albeit only at 320 x 200 is not extrordinarily long for a GI render. Depending on complexity you can be talking hours for a decent render and size.

You can alter the settings but more than likely you will start to see artifacts in your render. In addition if you are using raytracing and refraction in combination with GI this will slow up the render immensly and you might want to look at ways of maybe blagging this area with reflect maps etc..

Also and I might be teaching Granny how to suck eggs, but whilst creating your scene keep all the setting reasonably low until you go for the final completed render.

Hope this helps.

RPG

http://rpgdigital.bizhosting.com

[baby]

nb : max 5 GI render is quite slow above all !!!

[Anton Andriesh]

Thank you!

Can anyone help me? How can I make it qualitative? How can I make walls to reflect light? Without raytracing I mean.

Here's my Advanced Lighting parameters:

Global Multiplier: 1.0
Sky Lights: 2.0
Rays/Sample: 600
Filter Size: 2.0
Ray Bias: 1.0
Cone Angle: 90.0
Object Multi.: 1.0
Color Bleed: 1.0
Bounces: 5

1 Light Source. No raytrace. Only low poly.
Rendering time: app. 10min ona P4 2,5 Ghz.



Thank you again. Here's my image:

[googlo]

Try applying an Advanced Lighting Override Material to your wall materials and increasing their refelctance value. You might be able to get by that way, but you'll have to play with the settings and see what else could work, I'm new with it too :) . Also the ALO material won't destroy your wall material, it becomes part of it for lighting control purposes like this one for individual objects in a scene concerning the new GI options in Max.

[lwl525]

rediation GI is better in max5 if the light bouced several times in the scene

[RPG2006]

I think I've found the answer.

It recommends in the reference to use radiosity instead of GI in indoor scenes. I know this isn't strictly the case, but I setup a similar scenario for testing.

After messing around with GI and the adaptive undersampling etc I switched over to radiosity. marked improvement speed and results.

You need to reduce the multiplier on your skylight down to .2 or .3, set initial quality in the radiosity panel to 90% say, and in the rendering parameters you can get away with something like 256 rays per sample, but for starters try less.

Also try putting adaptive sampling on for starters. Something like 4x4 initial and 2x2 subdivide. If you uncheck adapative you will be on the highest setting. Good for quality not so for speed.

You will have to hit the start button in the radiosity panel first to calculate, it takes a second at these settings and then hit render.

Like I say marked improvent and also you have the advantage that you can store a light solution and rerender.

Hope this gives you some success, and thanks for making me have a tinker.

RPG

ps. If you find out anything else, do let us know

[Q_B]

Greetings. I'm not very xperienced with GI yet, but i've been havin some problems and i solved lots of them by tunning the exposure control. you MUST have exposure control on for realistic results. Check in the help files, there says if u have sunlight, then u MUST set the light scale up to 90000 or so (standard 1500). Try it :)

[Chris Thomas]

Can you post your file so I can have a tinker?

Chris T

[Anton Andriesh]

Sorry, I can't post the source. It's not my personal project.

I allready done it, but with radiosity.. now it renders faster, but there are still some problems with light reflectance. I can't understand how are they calculated. A surface should reflect light only when its illuminated. So.. how can you explain this image: :)

[godlyclassic]

wow.Good!

[Anton Andriesh]

Why textures and maps aren't seen after applying radiosity?

[Q_B]

Well, since u'r on to usin radiosity instead of light tracer, maibe u can try it like this:

1 - Use medium quality for the solution, for start, lets say about 30 - 50%. When u get the results u want u can raise it to higher values.

2 - Go to the meshing size and use values lower than 50 cm, it will divide your walls in small polys and calculate the iluminance for them, instead of big chuncks of the wall.

3 - Don't bother to use regather until u get the ilumination solution right. It will only do what u get in light tracer, that is , "indirect shadows".

4 - And don't forget to set the exposure control right. Use logarithmic xposure.

Hope it helps :)

[Anton Andriesh]

Thank you, QB!

I knew that logarithmic exposure is used for radiosity, but still I haven't managed to to apply it. I tried changing its settings but image is oversaturated. It has better results with automatic exposure, I don't know why.

Here's the image:

[Anton Andriesh]

forgotten :)

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