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wizlon
10-02-2007, 10:13 AM
Is it possible to achieve the look of the blinn materials specular reflection with the mia material? even though I guess it's not physically correct it looks much more natural. I've tried all options on mia i.e. highlight vs reflection balance, visible area light reflections only, highlight only etc. but nothing gives me the desired result.

Has this changed with mia material x?

Also note the weird reflections.

wizlon
10-02-2007, 10:15 AM
closer view.

Gabba
10-02-2007, 05:31 PM
Look at this =)
http://forums.cgsociety.org/showthread.php?f=87&t=521552&highlight=blinn
Cheers

Gabba

wizlon
10-03-2007, 09:27 AM
I do remember reading that now, thanks for jogging my memory Gabba.

Some might say that this is physically incorrect, but it's not a surface property that i'am trying to emulate, it's an effect as quoted from Master Zap in this thread

http://forums.cgsociety.org/showthread.php?f=87&t=543646

'And yes, this would happen to a superbright pixel also in a real digital camera. However, intra-pixel bleed and glare tends to cover this up, it can sometimes be evident in a photographed image.

So... how do you get around it?

Well, there are two basic fixes:

a) Do what reality would do, and cover up the effect with glare.

In a real optical system, such superbrights would spill onto neighbouring pixels due to lateral scattering in the imaging surface (film, ccd, or retina of eye) or scattering inside the optical path (lenses, the optical goo inside the eye) and - to a much lesser extent and much less than people think - scattering in the atmosphere.

There are numerous shaders and tools to do this, from "glow" filters in photoshop, the Lume "Glare" shader that ships with max, Maya Glow, etc. etc. that all "does the job"... pick one. Use it. Enjoy.'

Cheers.

Lee.

danylyon
10-03-2007, 10:12 AM
Under normal circumstances I don't think this would be glare but rather little imperfections in the chrome, that slightly blur the reflections. You could fake that if you layer two shaders on top of each other (a very blurry one and a perfect chrome one).

This would be the most realistic way. But also the most renderintense.

Glare is always good aswell, but it's a different effect, it would blur over the edges of the chrome ball.

wizlon
10-03-2007, 10:30 AM
I agree some of this would be down to imperfections in the surface, but it's the effect described by Master Zap that I really want to achieve.

Here's the mia fix as explained by Gabba/wurp.

Thanks all.

MasterZap
10-03-2007, 01:14 PM
Is it possible to achieve the look of the blinn materials specular reflection with the mia material? even though I guess it's not physically correct it looks much more natural. I've tried all options on mia i.e. highlight vs reflection balance, visible area light reflections only, highlight only etc. but nothing gives me the desired result.

Has this changed with mia material x?

Also note the weird reflections.

This is a visible area light - right?

Looks like what you are after is a mix of traditional "specular highlight" AND a reflection of the "visible area light". mia_material(_x) by default does not add specular highlights of visible area lights, since that would be redududundant. But it's an option, so you can just turn it off....

But if you really want the "Glare" effect, well, you need a Glare filter of some sort. None ships with Maya at this time, but there is one w. max in the lume shaders.... (oh, look, a bird)

/Z

wizlon
10-03-2007, 02:17 PM
Thanks Master Zap, but I can't use the Max lume glare shader because i'am on OSX.

The 'reflection gloss 0 samples' cheat described above is the best solution for me right now.

What would be cool is a lume glare shader for Maya that could be rendered in a separate pass, the same as available in Max.

MasterZap
10-03-2007, 02:32 PM
Ah... OsX. Gotcha. Hmm. JS_Glare (www.pixero.com) is available in source code. Some smart guy with a Mac (don't look at me! ;) ) could compile it for OS X I guess(?)

/Z

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