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Yarim
05-17-2009, 08:26 PM
Hey guys where on earth do I assign Object Id's and material Id's to my passes??? I cant find any of this in the manual.

JeffrySG
05-17-2009, 08:30 PM
I seem to recall that the Object ID never really worked. The material IDs just assign a different gray level to each material. The material ID does not get anti-aliased and you'll need to do a levels adjustment if you want to see the different masks visually as they are usually one shade of gray apart from each other. Typically, I have not found either one very useful the way they are implemented.

So... you don't need to assign them anywhere. It's automatic for the Material ID. And the Object ID doesn't work. If I remember correctly, that is.

Yarim
05-17-2009, 08:46 PM
lol! Great.... Well i have another trick.....
But only works with 3 object scenes....
1 blue 1 green and 1 red

and subtract them from the red green and blue channel in the compositing software to issolate them... also works on lights.... but about the material id i dont have a clue what to do... i was just curious

Lightwolf
05-18-2009, 01:38 AM
The material ID does not get anti-aliased...
And it shouldn't be. If you think about it, suddenly the edges of an object with material "chrome" would turn into "plastic" because that's (numerically) half way to the material id of the "metal" object right behind it.
The same goes for objects IDs.

Cheers,
Mike

littlewaves
05-18-2009, 06:39 AM
are you talking about the object id in the psd buffer export plugin?

Yeah that doesn't work here either.

I seem to think there have been a few problems with the buffer export image filters.

like this one with rpf passes http://www.newtek.com/forums/showthread.php?t=95411

JeffrySG
05-18-2009, 07:19 AM
And it shouldn't be. If you think about it, suddenly the edges of an object with material "chrome" would turn into "plastic" because that's (numerically) half way to the material id of the "metal" object right behind it.
The same goes for objects IDs.

Cheers,
Mike

Ahh... that's true Mike! Good point! :D

StereoMike
05-18-2009, 07:28 AM
Wouldn't different shades of gray work for keying? I think it would.

Yarim
05-18-2009, 07:30 AM
The material ID does not get anti-aliased a

Antialliased, or you mean premultiplied?

Lightwolf
05-18-2009, 09:55 AM
Antialliased, or you mean premultiplied?
Premultiplied with what?

Cheers,
Mike

JeffrySG
05-18-2009, 10:20 AM
Antialliased, or you mean premultiplied?

No I meant anti-aliased. But as Mike said, this needs to be this way.

JeffrySG
05-18-2009, 10:21 AM
Wouldn't different shades of gray work for keying? I think it would.

Yes, it should. It just might be hard to visually see where the keys are. And again, the masks are not anti-aliased. Just something to be aware of.

monovich
05-18-2009, 02:54 PM
you just need to render 2x or 3x and scale down, at least that is what I do.

you can create your own ID and surface passes with nodes and gradients, I did it once and it worked by assigning a level of grey per id #

Julez4001
05-20-2009, 09:20 AM
you just need to render 2x or 3x and scale down, at least that is what I do.

you can create your own ID and surface passes with nodes and gradients, I did it once and it worked by assigning a level of grey per id #

Could you explain/show how one would do this?

monovich
05-20-2009, 10:55 AM
I'll look for the node tree. I think I saved it somewhere, but I'm not sure which project I used it on.

monovich
05-22-2009, 03:33 PM
http://newtek.com/forums/showthread.php?t=82267

check towards the bottom for my post and node tree attachment.