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MARW
08-26-2002, 07:56 PM
Hello, I have a bottle standing on a reflective plane. I have several objects only visible in reflections that I want to be visible in the bottles reflections but not in the reflective plane. At the same time I want the bottle to visible in the same reflective plane, How do I render this with raytracing?

Is there no technique for blocking specific reflections? It should not be that different from blocking a light source on a specific object, right?
MARW
08-28-2002, 08:10 AM
PLz, does no one know this?

Is there perhaps som god comp. technique for this effect?
svenip
08-28-2002, 10:57 AM
select one of the objects and go to the AE. there is a section where you can set the render options. uncheck "visible in reflections".
MARW
08-28-2002, 12:53 PM
But then you wont be able to se the object in the bottles reflections..
alexx
08-28-2002, 03:46 PM
i think maya can not help in your case since there is nothing like a connection which help you to say which object can be reflected in another one and which not (i think max has something like that)

to fix that you will have to render different passes and then later do the job in post.

you may notice the missing reflection pass at that point in maya:
you have to render the complete beauty pass and then the diffuse pass and subtract them from each other to get the reflection passes..
have fun

cheers

alexx
webster
08-28-2002, 07:04 PM
Well,

Itīs just a theory, but couldnīt You take the material and connect it to a layered Shader as Input 1 and take a Lambert or Surface Shader as Input 2 and animate the sliders ?

webster
graphiouz
08-28-2002, 07:18 PM
im not sure if i understand your problem, but have you tryed the light-link function?? if you wanna block specific objects from specific lights thats the tool to use.

.
MARW
08-29-2002, 09:13 AM
No, I actually want to use kind of the same function as the light linker, but instead of turning of a specific light, I want to turn of a specific object.

If you look at the connections from the light linker you see some kind of connection. Shouldn't you be able to do the same between objects?

Alexx:
I’m not that familiar with comp. in post. So I’m not sure what you mean with Beauty pass. I use AE. Is it not enough to render in to passes to Targa, then use the alpha as transparency (interpret footage). The bottle would be one pass and the "ground" would be the second.

/marw

ps. Webster: I not sure if I know what you mean.
svenip
08-29-2002, 09:45 AM
you can set the passes to render in the render globals. there is a folder (the fore last one) calles render layers/passes.

there you can set which pass you wanna render.

alexx : isn't it the specular pass which makes out the reflection ??? only in highlights you can see reflections. and the difference between the beauty and diffuse should be specular.

so it should be the specular pass, or ??

hmm, i have to think of, because i have no maya in front, because i'm moving to berlin right now
DesignDawg
09-06-2002, 10:42 PM
Alexx,

What exactly do you mean by "Subtract the images"? I've seen you say this in another thread.... What are you using to do this, and how?

Ricky
alexx
09-09-2002, 08:22 AM
ok..

see the attached image.

i have an image with the reflections and one without.

i use shake (but possible in any package - even photoshop) to subtract the two images, which gives me the reflections as a resulting image.
that image i blur to get the wanted blurred reflections.

since these get bigger now i use the mask from the sphere to cut away the unwanted reflections which are no longer over the sphere and add that result on the starting image that had no reflections..

cheers

alexx
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