So I wanted to create an object with a light shining out of it. Here is the problem. With the fall-off set just outside the model, it's strange that the light bleeds out of a solid object.

Attached is a screen shot of a test 'bucket' with a light 'bone' in it. The choreography has had all other light sources removed. I've also attached the test project.

Anyone have any pointers? Am I doing something wrong?

??? :confused:

Is darkness set to 100%? (It defaults to 80%.)

Try setting your shadow darkness to 100%.

I tried going to 100%, it didn't seem to help. Light seems to penetrate all the double walls, even adding a third doesn't seem to help with the bulb light. I changed to a kleig and you can get the effect I think you want. Very strange, it only seems to be the bulb that leaks, I would send in a trouble report.

I made a two wall object centered the bulb at the top turned on shadows had the fall out within the walls and got this with the light intensity set at 500%


Click to view attachment

Click to view attachment


with the rim light on


Click to view attachment

Turned the shadow darkness to 100% and it looked okay with the bulb, BUT volumetric lights do not get corrected by this... REALLY bad... see screenshot.

Bruce,

Kleig lights are what I need to avoid since they bleed too when they are too large, especially on multipass. Plus, you can't focus a Kleig light tighter than say 10% without some serious bugs. (Volumetric light disappearing, diffuse light disappearing, etc.)

I was kind of hoping to focus a volumetric Kleig originally, but you can't go past 0% to focus it down and the shadows on volumetrics don't seem to render properly... again, I may be missing a setting.

Also, in V14.0Beta2, I notice that if I play with light settings too much, they start not behaving properly. i.e. - suddenly volumetrics won't work, diffuse disappears regardless of intensity, etc.

I figured if I aimed a light (either light bone in the model or light dropped into the choreography) from inside an object it SHOULD project the appropriate shadows outward. Seems that is not the case, at least not consistantly. I saw this before on some external 'running lights' I made for a space ship I was working on. If the light was placed inside of a modeled cover or lens, the light was able to bleed to other surfaces. Now I didn't know about the shadow darkness setting before, so it may have been that simple.

I'll do some more experiments tomorrow and keep you posted. I'll try and make quite a few different scenarios, so there is no question whether it's a bug or not.

100% darkness shadows would help out greatly, but remember that a minimum of 2 ray casts is needed to prevent light leakage. If you use only one ray cast, A:M will simulate a quike and dirty penumbras with gradients.

For a believable volumetriceffect, i would sujest at leatst 200% quality, 10% brightness, 80% contrast. The use of a light gell can also make it more realistic, though a higher quality volumetric is required to prevent pixelization inside the beam.

Here's the page matt made for lights. Volumetrics is about a third of the way down.
http://wikiold.hash.com/amfeatures/published/Objects-Light

hope that helps

Dan,

Thanks, I'll do some more playing around with the rays cast and such and see what I can find out.

Have you done any experiments with a mesh lens in front of a light source? Or is that what you mean by using a 'light gel'?

I have tried in the past to use lenses to bend and shape light, but A:M just isn't that kinda program, so it's more viable to use a light gel, wich is simply a color image that the light uses as a rotoscope; it's sort of like a computer projector.

there's a cool metal grate light gel on that page if you want to check it out

Use a separate light for volumetric and diffuse/specular. It's hard to get a volumetric the way you want it and have a good diffuse light as well. Make sure that those are the only settings set on the lights (ie your volumetric light only cast volumetrics). I also don't suggest using Spherical volumetric because the nature of spherical volumetric prevents it from having a very bright core.

If you're talking about using a patch with a transparency on it, then yes, the volumetric will act as you would expect, but only for Klieg lights. Spherical volumetrics are somewhat sketchy.

Thanks for the replies fellas. Still doing some testing but I think I've just about settled on the klieg light with specific settings for my application.

I did notice one irritation. With a wide klieg light, if you set it as wide as the opening or just a hair smaller and then use multipass, it 'shifts' the light around to make the shadows softer. The result is the light 'pops' out through the geometry again.

To correct this, I reduced the light to about 2/3rds the radius I need to fill the opening and then it keeps inside the mesh.