Sun, Jan 26, 12:05 AM CST

Renderosity Forums / Bryce



Welcome to the Bryce Forum

Forum Moderators: TheBryster

Bryce F.A.Q (Last Updated: 2025 Jan 23 6:01 pm)

[Gallery]     [Tutorials]


THE PLACE FOR ALL THINGS BRYCE - GOT A PROBLEM? YOU'VE COME TO THE RIGHT PLACE


Subject: IB-(A)-L Image Based (Ambient) Lighting...An experiment


  • 1
  • 2
Rosemaryr ( ) posted Tue, 19 February 2008 at 9:05 AM

While these images can do the job, I wouldn't call them 100% successful.  But that's the whole point of experimenting.

I've realized doing these, that if you want a clear image to use as a backdrop, or are using highly reflective materials, then it's best to use one of the high-res images available on the web.  But if your goal is to provide 'mood-lighting', then one of these types of simpler color 'splotch' images will do the trick nicely.  It all depends on what your goal is for your render.

RosemaryR
---------------------------
"This...this is magnificent!"
"Oh, yeah. Ooooo. Aaaaah. That's how it starts.
Then, later, there's ...running. And....screaming."


FranOnTheEdge ( ) posted Tue, 19 February 2008 at 4:00 PM

Interesting effects, so what sort of set up are you using in a scene to test these?

Could you let us in on what is or isn't working as well as you'd like and what you think might improve things?

What settings are you using in the IBL Lab?

Measure your mind's height
by the shade it casts.

Robert Browning (Paracelsus)

Fran's Freestuff

http://franontheedge.blogspot.com/

http://www.FranOnTheEdge.com


Rosemaryr ( ) posted Wed, 20 February 2008 at 9:29 AM

My general IBL /sky lab settings are as described earlier:

Usually the sunlight is disabled, and no other lights are in the scene.  The IBL settings, usually:

Quality: 256 (about half)
Intesity: 5-15, (depending on how bright the image is to start with)
HDRI effect: 100

I am not using any reflective objects in my tests; these just show the pixelation of the HDRI far too much... and my focus was more on the effects of these colors on non-reflective surfaces.  So the objects in my scene are all flat white diffuse color...from the 'Simple' category of the materials.

Most of my finished renders tend to be Poser people, rendered out in Bryce, so unless they are wearing or using glossy metal armor, the lighting information I need is more oriented to how these colors will look on skin tones, or leather/cloth/etc.  What I've found is that the non-glossy/ matte surfaces will 'blend' the IBL image's colors into a smooth gradation.  This smooth gradation can give me the effect I previously had to get  by adding a whole bunch of colored lights...which slows down the render times.  Now, with just the IBL, and maybe either the sun, or one added light for shadows, I can get the same results for much less work.

RosemaryR
---------------------------
"This...this is magnificent!"
"Oh, yeah. Ooooo. Aaaaah. That's how it starts.
Then, later, there's ...running. And....screaming."


Vile ( ) posted Tue, 26 February 2008 at 5:51 PM

I am still not sure what the point of this exercise was and my head hurts from the colors. LOL If you are using a single or even multiple color image from this technique saved as a .hdr are you only creating an easier way of making ambient light? Is this faster then using True ambience.


Rosemaryr ( ) posted Wed, 27 February 2008 at 9:01 AM

"Is this faster then using True ambience.?"

shrug  I haven't got a clue, Vile.   I haven't done any investigations into the comparative uses of TA vs. hdri.   This was purely an exercise in self-created hdri applications.  There are so many things about Bryce I still don't know after all these years playing in my fave program.  My to-do list is already a mile long, and it grows daily.  

RosemaryR
---------------------------
"This...this is magnificent!"
"Oh, yeah. Ooooo. Aaaaah. That's how it starts.
Then, later, there's ...running. And....screaming."


Vile ( ) posted Wed, 27 February 2008 at 7:56 PM

I think you were just trying to make me dizzy! :P


Rosemaryr ( ) posted Thu, 28 February 2008 at 9:20 AM

Retaliation for that hypnotic staring green eye of yours, that's all!   grin

But, in terms of a thought-experiment,  it would seems that the two functions would do essentially the same thing, but, for True Ambience you would actually need to have the objects in the scene to create the ambient light, whereas with the lighting from the hdri images, you could 'fake it', thus saving yourself some mesh weight in the scene......
Just a guess....the hypothesis would have to be tested.

RosemaryR
---------------------------
"This...this is magnificent!"
"Oh, yeah. Ooooo. Aaaaah. That's how it starts.
Then, later, there's ...running. And....screaming."


Rayraz ( ) posted Fri, 29 February 2008 at 12:22 PM

IBL and TA do entirely different thigns.

IBL simulates light cast by a dome around the scene, and doesnt include any calculations to attempt to estimate how light bounces off objects.
TA simulates indirect lighting throughout the entire scene, not just the sky, but other objects in it too, including an estimation of bounced light. Actually you can even control the amount of bounces with the ray depth.

(_/)
(='.'=)
(")
(")This is Bunny. Copy and paste bunny into your signature to help him gain world domination.


  • 1
  • 2

Privacy Notice

This site uses cookies to deliver the best experience. Our own cookies make user accounts and other features possible. Third-party cookies are used to display relevant ads and to analyze how Renderosity is used. By using our site, you acknowledge that you have read and understood our Terms of Service, including our Cookie Policy and our Privacy Policy.