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Eightball
03-16-2007, 12:04 PM
Hi there!

I've been working on a pretty simple scene for a school project. There i have an iPod kind of model laying on a plane and i've got some (invisible) white planes hanging in the air above to get some extra highlights on the model.

now, since the groundplane (using "usebackground-shader") is reflective, i get white reflections of those planes on the groundplane, too. but i only want to have them on the real model.

sound confusing, i know, but i hope you know what i want. (my english isn't THAT good, i guess)

so can you guys tell me how to prevent getting reflections of the white planes on my groundplane but keep having them on the model?

thanks in advance

Alex

p.s. i used the search funktion, but unfortunately nothing useful came up
scrimski
03-16-2007, 12:13 PM
Which program do you use?

In Max you could do this via right-clicking the object->Properties.
Eightball
03-16-2007, 12:29 PM
oh right, sorry.

i'm using maya 8

Alex
Eightball
03-16-2007, 05:52 PM
is there nobody who knows how to solve that problem?

i bet it's so easy... please help ;)

Alex
Rock_Lee
03-19-2007, 08:16 PM
Hey eightball,

Off the top of my head you are probally using raytrace shadows...so you need to turn down the reflectivity of the material you have assigned to the ground plane all the way to zero, so the reflections of the white planes you have setup won't show up on the ground and only on your i-pod...why are you using a "use background shader" for the ground plane?...I am just curious as to what effect you are trying to achieve with that shader...I'm not very farmiliar with it...neways I hope that helped
Eightball
03-19-2007, 10:24 PM
Thanks a lot for replying.

Though i already posted my issue in the maya forum and found a solution there. I'm rendering with renderlayers now, not exactly what i was hoping to get, but it's good enough.

I actually wanted du keep the ipod reflecting on that ground plane, that's why i used a use background shader.
you see what i mean on the attached renders. number one is only the model rendered, you can slightly see the highlights. number who is only the groundplane rendered, which reflects only the model and the last one is the final composition.

Thanks!
Alex
Cameo
03-19-2007, 10:53 PM
I was going to post about this the other day but I couldnt think of an elegant way to do what you wanted. The problem I kept coming back to was that getting a reflection in the ground of the ipod without the reflection in the ground of the white planes is pretty straightforward. What isnt (as your comp proves) is getting a reflection on the ground of the ipod which features the reflection of the white planes. The only way I thought was to render in passes like you have and cheat the ground reflection, but even that is only really possible for a still. If animated it would be a nightmare. If you're happy with what you've got then cool, dont give yourself the additional headaches :D
Eightball
03-20-2007, 03:16 AM
actually, it is animated ^^

pretty simple to be honest, but it's a short linear animatien where the camera moves along the side of the model. after all it's about 500-600 frames, but i can simple composit them in after effects.

the only thing i don't get in the end is the refractions of the "lighting-planes" on the ground, since they don't even exist in the "ground-render-layer"

sorry i'm making this so complicated

anyway, it's done now,... finally... ;)

Alex
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03-20-2007, 03:16 AM
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