*URGENT* Mental Ray GI Problem

[stunndman]

the amount of photons doesn't really influence the intensity - try decreasing the energy of the light (in the mental ray tab of your light)

on AW's site there are mental ray video tutorials - on GI,FG,Caustics,...

[stunndman]

and maybe try lighting a simple scene first (a cube or something)

[Jozvex]

I think Final Gather would be more like what you are wanting anyway.

[Sieb]

Mental Rays version of GI is a daytime lighting simulation, if it is, lower the energy. Photons control how much light is emitted, but energy the intensity. If what you are looking for is the infamous Brazil GI, either use Final Gather or load up the GI_Joe script.

[Dirk_P_Ho]

Ok, I might try GI Joe if i dont have this settled out.

Covering the Scene, i have a half sphere with just a blue lambert on it....the image only gets blown out with the sphere unhidden, otherwise the overexposure collects around the edges of the buildings..

This render (if you want to call it that :) ) was with final gathering added with the default 1000 rays

I lowered the emmiting lights energy for the photons to 2000 for RGB down from the default 8000.

Since stunndman said that the number of photons doesnt affect the intensity, I put them back to the default of 10k.

Thanks a lot for your help just, really appreciate it.

[Dirk_P_Ho]

K, photon energy is now at 100 for rgb, still getting overexposure and wierd colors. Still a wierd hotspot on the right.

Ignore the crappy textures :)

[stunndman]

either try GI or FG - handling both needs exponentional skills (something like that) - for GI you don't need a sphere with indandescence

you will not need more than 100 rays for FG for starting out - 1000 rays is way too much - i haven't gone beyond 300 rays so far

have you checked out the tutorials i mentioned ? they are something like 2 minute videos and they will really enlighten you

start with FG - it's easy - create one light - a point light or something - it doesn't matter - sets its intensity to 0 (maya's light intensity i mean) - it's just there to avoid the creationg of the default light

create a half sphere (that's covering your scene like a sky) - turn its color down to black and its incandescene to white or something (later on you can assign a ramp to the incandescence color to get a more subtle FG lighting)

enable FG (disable GI) in your MR settings - set your rays to 100 - leave everything else as it is by default- render - that's it

now you can play with the max radius value - set it to 10 - set it to 100 - whatever looks better - leave the min value at 0

that should be it

[Dirk_P_Ho]

K, thanks a bunch, ill check em out

[Jozvex]

Are you still using that directional light?

Because I've found that directional lights are really really bright when using MR compared to other lights.

[Dirk_P_Ho]

Ive actualy given up on MR for this scene, im gonna use GI Joe

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