Lights and Material Question

# 1 15-07-2008 , 12:59 AM

Registered User
Join Date: Oct 2007

Location: IL

Posts: 738

I'm trying to mode my lamp and I have a problem with the light:
This is how it looks when it's off-

and on (sorry about the poor quality, but I AM photographing a lamp after all. still, it is good enough for my purpose...)

I've modeled It's bottom and added an ambient and point lights.
this is it without the lights:

and the renders:

the problem is, as I understand it, is that the light does not effect the faces that are directed away from it, even though the object is partially transparent.
I've got raytracing and shadows(for the point light) on.

Does anyone has an idea for how to make this look more realistic?
Also, How can I make the materials closer to the real thing?

When in doubt, delete history and freeze transformations.

My latest snake game
(Requires DirectX9 SDK and Framework)

Quote

# 2 15-07-2008 , 09:49 AM

Subscriber
Join Date: Feb 2006

Location: Australia

Posts: 2,752

add glow.

mirek user added image

take it easy and life will be easy

Quote

# 3 15-07-2008 , 11:45 AM

Registered User
Join Date: Oct 2007

Location: IL

Posts: 738

I've got three problems with glow:
-It won't emit light as well as a light
-It creates distortion
-It doesn't effect the lid's color as much
... :headbang:
Benny

When in doubt, delete history and freeze transformations.

My latest snake game
(Requires DirectX9 SDK and Framework)

Quote

# 4 15-07-2008 , 12:14 PM

Subscriber
Join Date: Feb 2006

Location: Australia

Posts: 2,752

its not supposed to emit light.., thats what the lights are for.., one must mix and match!!!

what distortion.., got a pic??

the lids colour is done with the materials like a lambert.., but im guessing you might want a blinn for this.., not sure if lambert has glow??

take it easy and life will be easy

Quote

# 5 15-07-2008 , 12:33 PM

Registered User
Join Date: Jun 2004

Location: Cleveland, Ohio (USA)

Posts: 1,541

look into translucency?

(transparency doesn't affect the actual object, it just makes the object less opaque or less visible... keeping transparency at 0% and increasing translucency is probably more of what you're going for, since it actually allows the light to go through the way you're thinking of...)

Accept no substitutions.

Last edited by NeoStrider; 15-07-2008 at 12:37 PM.

Quote

# 6 15-07-2008 , 01:10 PM

Registered User
Join Date: Oct 2007

Location: IL

Posts: 738

Mirek:
*The problem is, that the material does not allow light through, while still looking realistic when there's no light.
*Distortion:

(view full size,because it's too small for the thumbnail)
*I tried lambert and blinn, and currently it's on phong (I don't really know the difference, It just looks better).

NeoStrider:
can you please give me a quick explanation about translucency?
*What is translucence depth?
*What is translucence focus?
*How does it work?

keeping transparency at 0%

Originally Posted by

By that you mean full(black) or empty(white) because at 0%(white) the translucency doesn't seem to matter much(so is everything else)

Oo, and thanks people
Benny

When in doubt, delete history and freeze transformations.

My latest snake game
(Requires DirectX9 SDK and Framework)

Quote

# 7 15-07-2008 , 01:34 PM

Subscriber
Join Date: Feb 2006

Location: Australia

Posts: 2,752

im not sure what you mean.., you dont put a light inside an object shaped like a light and expect the light t gp through?? its just an object!! if you want the light to go through.., go to the light linker in relationship editors and unlink it from that object.., hope you have it named well so you know which object it is.
from there you can make it illuminate some things while not illuminating others.

also in the AE render stats for the object (light cover i guess) you can turn things on and off there too.., such as 'cast shadows, visibility, ect.., reflections and such.

take it easy and life will be easy

Quote

# 8 15-07-2008 , 01:45 PM

Registered User
Join Date: Oct 2007

Location: IL

Posts: 738

useful tip, but...
You're missing the point. I could just put the light outside the lamp. I want the light to illuminate the glass and the environment from inside the lamp. In other words, I want it to be realistic.
I'm not looking for shortcuts... I want to learn how to do it right!
Benny

When in doubt, delete history and freeze transformations.

My latest snake game
(Requires DirectX9 SDK and Framework)

Quote

# 9 15-07-2008 , 03:43 PM

Subscriber
Join Date: Feb 2006

Location: Australia

Posts: 2,752

its not a short cut.., thats how its done. as i said you cant put a point light inside a sphere (lamp shader) and call it the correct way.., maya is not the 'real world'???

you will need advanced shading techniques for inner and out glow.., from a 'lamp.'

do a google for what you are looking for.., if its possible it will be on u tube.., maybe i just dont understand what you want.

someone else might be able to help.., didnt strider mention translucency..?? look at the sliders on your materials AE.., the one below colour

take it easy and life will be easy

Quote

# 10 15-07-2008 , 04:31 PM

Senior Software Developer
Join Date: Jan 2005

Location: Livingston, Scotland

Posts: 1,701

Originally posted by BennyK
useful tip, but...
You're missing the point. I could just put the light outside the lamp. I want the light to illuminate the glass and the environment from inside the lamp. In other words, I want it to be realistic.
I'm not looking for shortcuts... I want to learn how to do it right!
Benny

Originally Posted by

To get the feel you are looking for you are not going to get it with one light...

Use The glow effect from the bulb then use light linking on the main light to ensure it lights up only what is required...

Then use a secondary light (i would use and ambient light) and play with the intensity to get a nice highlight around the object...

In real life light is infinite... In Maya is does not simulate the same way as it inpracticle for a computer to continue to compute light to infinity and it would probably crash...

So for your scene (in a nice simple way) use a glow on the bulb, set light to point out in the direction of the bulb (parent it to the bulb so if its moved it moves with the bulb). Once done create an ambient light and use light linking to light up only what is required (the surface of the light) and keep the intensity really low. Work with that and play with the settings until u get the right feel...

Translucency in easy terms is like skin... A Translucent Object is an object that appears to be solid, but allows light to pass through it. All skin is Translucent and this is the basis of the Sub Surface Scatter materials used to simulate skins behavoiur to light. Shine a Torch into your hand and it emmits a red glow on the other side. Translucency at work user added image

Some lightbulbs are either transparent or translucent:

Transparency = Invisibilty
Translucency = Solid, but allows a certain amount of light through.

Anyway hope this helps and keep at it, lighting is one of the more difficult subjects to master. Big Studios have entire departments dedicated to lighting scenes, so dont feel bad and good luck.

Chris (formerly R@nSiD)
Twitter
When the power of love overcomes the love of power the world will truely know peace - Jimmy Hendrix

Winner SM VFX Challenge 1

3rd Place SM SteamPunk Challenge (May 2007)

Quote

# 11 15-07-2008 , 04:36 PM

Registered User
Join Date: Oct 2007

Location: IL

Posts: 738

Thanks Mirek,
I just watched a tutorial, mainly about shaders, and I think I'm beginning to understand how this kind of things are done...
I'll play around with it some more and post the outcome later...
Thanks for all of the support
Benny

When in doubt, delete history and freeze transformations.

My latest snake game
(Requires DirectX9 SDK and Framework)

Quote

# 12 15-07-2008 , 09:13 PM

Registered User
Join Date: Oct 2007

Location: IL

Posts: 738

Progress...

I've worked on it a bit and I quite satisfied with the result:

I used Mirek's advice about the light linker, and added a spot light to illuminate the lamp, added some glow, some ambient and some incandescence.

Now I'm having problems with my couch though - I think it's quite obvious. It happens when I turn Raytracing on in my render global settings. Anyone knows why this might happen?
Benny

When in doubt, delete history and freeze transformations.

My latest snake game
(Requires DirectX9 SDK and Framework)

Quote