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GOBO

Posted: Fri Jul 09, 2010 5:05 pm
by gadzooks
What's the best way to do GOBO's? Do you add a black and white image as a layer on a emitter material, to mask the light? Or place a Plane with the black and white image in front of the emitter to block the light? I have tried both with little luck? Any suggestions?

Re: GOBO

Posted: Fri Jul 09, 2010 9:03 pm
by itsallgoode9
i would imagine the cheapest way would be to do a mask on the material. If you are using a separate plane as a gobo, light would be bouncing off the gobo and add extra, probably needless, calculations to the render.

How have you not been having any luck with either? It seems like it is something fairly straight forward .

Re: GOBO

Posted: Sat Jul 10, 2010 12:06 am
by Bubbaloo
Maybe it's a focusing issue. We had one in our office of our logo on the wall, and it required a focusing lens. I wouldn't think that you could have this effect with only an emitter material and mask. It's probably something that needs to be modeled.

Re: GOBO

Posted: Sat Jul 10, 2010 7:51 pm
by itsallgoode9
Bubbaloo wrote:Maybe it's a focusing issue. We had one in our office of our logo on the wall, and it required a focusing lens. I wouldn't think that you could have this effect with only an emitter material and mask. It's probably something that needs to be modeled.
thinking of it, you're probably right, it would be far too diffused using a material and mask.

Re: GOBO

Posted: Sat Jul 10, 2010 11:40 pm
by gadzooks
Im beginning to think that it does need to be modeled. Because the other two ways are not working at all.

Re: GOBO

Posted: Sun Jul 11, 2010 12:34 am
by zdeno
gadzooks wrote: Do you add a black and white image as a layer on a emitter material, to mask the light?
no
gadzooks wrote: Or place a Plane with the black and white image in front of the emitter to block the light?
yes
gadzooks wrote:Any suggestions?
must force light to have almost parallel rays. some long super black tube and very strong emiter near bottom. i think

Re: GOBO

Posted: Wed Jul 14, 2010 1:39 am
by jfrancis
A small light source and a gobo far from the light and near the shadow receiver will give distinct shadows.

A large light source and a gobo near the light and far from the shadow receiver will give very indistinct shadows.

Re: GOBO

Posted: Sun Jul 25, 2010 6:06 pm
by zak
You could place the gobo close to the wall or object and hide it from the camera, so its transparent. That could be a way to cheat since maxwell not showing any light beam.

Jesper
:)

Re: GOBO

Posted: Sun Jul 25, 2010 8:41 pm
by jfrancis
zak wrote:You could place the gobo close to the wall or object and hide it from the camera, so its transparent. That could be a way to cheat sine maxwell not showing any light beam.

Jesper
:?:
good point