Maya Training

Introduction to Hard Surface Modeling

Maya Training

Interiors and Furniture Vol 1 & 2 - Modeling & Cloth

Maya Training

Shading, Lighting and Rendering the Bedroom in MR

Maya Training

Robot volume one - Modeling with animation in mind

Maya Training

Spach-Alspaugh House the complete courseware

Maya Training

Burt The Cartoon Dinosaur Vol 01 - Modeling

New Maya Training

Robot Volume 02 - Hybrid Rigging
You are here > Home > SimplyMaya Community Forums
Loading

Welcome to Simply Maya

Please Sign in or Sign up for an account

Member Login

Lost your password?

Not a member yet? Sign Up!

Old 05-02-2008, 12:38 PM   #1
gubar
Registered User
 
Join Date: Mar 2007
Posts: 1,055
Thanks: 2
Thanked 59 Times in 56 Posts
Default Creating a lightbulb with final gather and GI

Hi,

I've been trying to create a lightbulb like effect using final gather and gi.

In the scene, there is a lamp, containing a bulb (just a lambert sphere) with incandescence (I've tried it with ambient colour too). There is a sphere containing the lamp.

The image shows the result I get. Tweaking settings, I get variations on this, though I don't get the kind of light bounce I hoped for. Couple of questions:

1) Will global illumination only work with a light actually emitting photons? I mean, it won't bounce light around if it's cast from an object acting as a light source?

2) How would you create a bulb in a setting such as this? I wanted to see what a scene looked like from a single light source, but with it's rays being bounced around the scene.

3) To make a lamp shade appear to have thickness, would you actually extrude the surface to give it depth, or is there a setting that can fake this? (with a brighter setting in this scene it is quite obvious it is a wafer thin surface).

4) Why is it that I can see the back surface colour of the shade, but not the surface closest to the camera? the shade has a high translucency setting but a very low transparency setting.
cheers,

gubar
Attached Thumbnails
 
gubar is offline   Reply With Quote
Old 06-02-2008, 06:49 AM   #2
NeoStrider
Registered User
 
NeoStrider's Avatar
 
Join Date: Jun 2004
Location: Cleveland, Ohio (USA)
Posts: 1,541
Thanks: 0
Thanked 2 Times in 2 Posts
Default

looking at the HSV settings instead of the RGB settings for the material's color, try changing the V value to over 1.000 to make the object actually illuminate the scene. i'd suggest starting at 10.000, and increasing from there if it's not enough or doesn't give you the effect you were hoping for.

at the same time though, you could just fake it by putting a glow on the sphere, and using light-linking you could illuminate the scene/lamp with a light with the settings you want.
__________________
Accept no substitutions.
NeoStrider is offline   Reply With Quote
Old 06-02-2008, 09:28 AM   #3
gubar
Registered User
 
Join Date: Mar 2007
Posts: 1,055
Thanks: 2
Thanked 59 Times in 56 Posts
Default

Hi,

I'm already using a very high value and this is still the result. You're right, I could just fake the effect - I would quite like to try and light a scene like this though, to see what it looks like with just one light source, dimly bounced around.

I guess this isn't the way to do it though.

Anyone else got any suggestions how they would go about this?

cheers

gubar
gubar is offline   Reply With Quote
Old 07-02-2008, 09:01 PM   #4
GioChrono
Registered User
 
GioChrono's Avatar
 
Join Date: Apr 2004
Location: Tunbridge Wells, UK
Posts: 354
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Hi,

if you are using Maya 2008 increase the value of the scale setting on the GI tab in render globals. You can use this on a pre-baked scene. just used HSV and increase the value exactly the same as for the material. It works like an exposure setting and will brighten or darken you scene accordingly.

Hope that helps.

Gio
__________________
Gio

Creator of The Talos Project

GioChrono is offline   Reply With Quote
Old 12-02-2008, 12:21 AM   #5
Falott
Registered User
 
Falott's Avatar
 
Join Date: Jan 2005
Location: vienna
Posts: 1,095
Thanks: 3
Thanked 20 Times in 18 Posts
Default

is this setting surrounded by something like a box, simulating a room where photons can bounce back? if not it is no mystery why your front side doesn´t get illuminated, because photons wont bounce back to hit it.
__________________
everything starts and ends in the right place at the right time.
Falott is offline   Reply With Quote
Old 12-02-2008, 12:23 AM   #6
gubar
Registered User
 
Join Date: Mar 2007
Posts: 1,055
Thanks: 2
Thanked 59 Times in 56 Posts
Default

Thanks for the posts guys.

Got some pretty serious computer trouble that is stopping me working just now, hopefully back to it next week and I'll get working and post back then.

cheers

gubar
gubar is offline   Reply With Quote

A little bit about who we are
Links you might find useful
Catch up with SimplyMaya
SimplyMaya specialises in Maya tutorials. We offer over 1,000 individual Maya training videos, ranging from basic Maya tutorials through to intermediate Maya tutorials. Our tutorials are created by instructors with industry experience and are designed to get you up and running in Maya quickly without making it seem like hard work.

Copyright © 1999-2015 SimplyMaya - vBulletin® Copyright © 2000-2015, Jelsoft Enterprises Ltd.