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roginafalengi
01-24-2011, 05:00 PM
Hey, I'm using mental ray in Maya 2011, I want to create a fully reflected shader for one of my objects, I want 100% reflective, exactly like a mirror, what shader should i choose (Blinn, Etc...) and what settings should I change? Thanksya!

musashidan
01-24-2011, 05:35 PM
I'm using Max/MR and the Arch&Design would be my choice. The Maya/MR equivalent is mia_x material I think. Check your Mental Ray helpfile.

roginafalengi
01-24-2011, 05:52 PM
Alright I assigned what you said but It doesn't reflects anything, what settings do you think should I change? (Assigned it to the other object, not the red one):
http://i535.photobucket.com/albums/ee355/2danimm/Umm.png
Here are the whole settings:
http://i535.photobucket.com/albums/ee355/2danimm/Ummm.png

roginafalengi
01-24-2011, 07:11 PM
I want mercury style shader (http://theintelhub.com/wp-content/uploads/2010/10/Mercury.png), Here are the other settings:
http://i535.photobucket.com/albums/ee355/2danimm/Mehh.png

Tora_2097
01-24-2011, 07:41 PM
If you are talking about the black spikey object ( I think I can see some reflections on it) you can do a couple of things:
A mirror like surface has little to no diffuse component so it should be a black diffuse color or a weight of zero.
Reflectivity at 1.0 is fine, if you scroll down to the rest of the settings (the ones that you not posted ;)
you should arrive at the BRDF tab. In there you could then rise the 0 degree reflection to something approaching 1, or set it to use the IOR instead in which case you have to rise this (IOR) value to something rather large- 20 or higher would be fine- although you'll not notice a great difference @ IOR greater than 10.

musashidan
01-24-2011, 09:16 PM
Also, you have to set up your scene/lighting to be conducive to reflections. Your scene has a grey environment so it will predominantly reflect grey. Try putting a .hdr in the environment, or some visible area lights/reflector cards. And tick the 'metal material' checkbox in the shader. Anisotropy/glossiness will play a big part also, depending on the metal you're creating.

roginafalengi
01-25-2011, 09:54 PM
Alright here we go so far after some work:

http://i535.photobucket.com/albums/ee355/2danimm/Diamond2417jpeg.jpg

the thing is, I really want it to look like a mercury style metal, do you remember in the pill scene in Matrix 1, after he takes the pill, he touches some kind of metal cold liquid that goes all around his body? I want this kind of shininess...
Setting so far:

http://i535.photobucket.com/albums/ee355/2danimm/Untitled-1.png

about the HDR, I know HDR means hyper dynamic range, but other then that i seriously don't have an idea what you're talking about.
how do i set my lightning to be conductive to reflections?
the scene is not grey, there's simply nothing there and i uploaded it as PNG, then it transparent.
about Anisotropy settings, what do you recommend?

Thanks for all the help so far!, helped me a lot.

musashidan
01-26-2011, 12:07 AM
about the HDR, I know HDR means hyper dynamic range, but other then that i seriously don't have an idea what you're talking about.
how do i set my lightning to be conductive to reflections?
the scene is not grey, there's simply nothing there and i uploaded it as PNG, then it transparent.
about Anisotropy settings, what do you recommend?

Thanks for all the help so far!, helped me a lot.

high dynamic images can be used as lighting, reflections, or both. There are several ways to implement .hdr images: I don't use Maya so I'll leave that to someone else, or you'll have to research it.
As I mentioned above, no matter how good your reflective shader is it will only look as good as the environment it's reflecting. That's what I mean by being conducive to reflection.
As for your scene being grey: If your scene isn't enclosed(from camera view) by geometry or there is no map in the background then the environment colour will be whatever the default is. In 3dsMax it's black. So it dosn't matter if you saved your image with an embedded alpha channel. Unless you change the background colour in Maya, (or apply an image map) your materials will reflect that colour.

andrewkennedy
01-29-2011, 09:45 PM
Alright I'm not that great at shaders but I think I can help with this. I take it from your description that you want something that looks like this?

http://img255.imageshack.us/i/mercury.png/

To create this shader, here's what I did:
1. Make a Phong
2. Turn the color down to a pretty low grey, about 15%
3. Crank the cosine power and specular color really high
4. Turn reflectivity all the way up.

I used image based lighting because you were wondering about HDR. Musashidan is right; since you don't really have an environment that's what's causing some of the dullness in your mercury shader. Since your environment is so dark and the shader takes on most of its color from reflections, it's obviously going to look dark as well.

High dynamic range simply means that the color values stored in the image are a higher range than normal. Using an HDR image is one way of lighting a scene in maya. If you have one, here's how you can use it to light your scene.

1. Open Mental Ray's render settings
2. Go to the Indirect Lighting options.
3. Select Image Based Lighting.
4. Choose the image by using the attribute window.

You generally don't want it to show up on your camera as a sky dome (since this is essentially what the IBL does). To fix that, turn off "Primary Visibility" in the attribute window. You don't need a HDR image for this to work. I actually just grabbed a jpeg of a test render I did for another project. Keep in mind though that HDR images work best if you're lighting something with an image.

I hope that's clear. If it wasn't then just ask for clarification and I'll try to help.

roginafalengi
01-30-2011, 08:36 AM
about the phong shader, that what i wanted it to be, i set everything like you said it came out pretty good.

about the HDR, you really helped me understanding the idea of hdr, thanksalot for this, i tried to do what you said in maya, added and HDR Image exactly like you said, turned off primary visibility, (this is the image 1500x1500 http://ict.debevec.org/~debevec/Probes/uffizi_probe.hdr) then rendered in preview quality with final gathering on, but got something pretty weird, I'm not sure which setting i should modify to get the thing better, if you can analyze this render it will help me so much (I have 3 directional lights in the scene):

http://i535.photobucket.com/albums/ee355/2danimm/HDR.jpg

thanks to everyone. :applause:

---------------------------------
EDIT: Listen, If i pump up the specular to the phong shader, it gets bright like in the image i uploaded, and it's really too much, but if i decrease it, it gets fine, but it doesn't reflects good at all.

andrewkennedy
01-30-2011, 09:31 PM
Try taking out the directional lights. The HDR image is going to light your scene pretty well. Try having only the image based light in the scene and go from there.

musashidan
01-31-2011, 09:33 PM
Or alternatively you could use a mia_x material.(arch&Design in Max) It's a much more physically accurate, energy conserving, fully ray-traced shader. Specular highlights are basically faked reflections based on a direct light source. A legacy workaround due to the computationally expensive fully ray-traced reflections. And although 'old-style' shaders such as phong obviously do have reflective properties-and are ray-traced- you will surely attain much better reflections with the mia_x material.

roginafalengi
02-02-2011, 06:37 PM
Hey guys, sorry for the late response, too many tests those days, anyways, i played with the lightning and I came out with this:
http://i535.photobucket.com/albums/ee355/2danimm/Lately.jpg

still using Phong shader, I decided to keep the Phong as the reflective shader, oh and used HDR, it's awesome.
this is it guys, thanks for the help with the rendering, you really helped me finding my way through all the options,

thanks again

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