HDRI visible on flat/Transparency objects, Plz help

# 1 06-11-2012 , 02:11 PM

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HDRI visible on flat/Transparency objects, Plz help

I have scene with HDRI environment, but I have issue with the visibility of HDRI on the glass and flat objects
Its very reflected(looks like mirror). its also visible on some part of the body as you see in the image.

any advice Here please.

regards

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# 2 06-11-2012 , 02:49 PM

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I think this is just normal reflection, or am I mistaken?

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# 3 06-11-2012 , 05:38 PM

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Yeah that looks pretty normal. Maybe some material tweaks are in order. Is that image tonemapped?

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# 4 06-11-2012 , 06:53 PM

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Hi guys Thanks for reply

I made a polygon sphere and I applied a surfaceshader material with HDRI . The sphere has been Uv mapped.

front Truck window's glass (material Phong and with reflection of 0.500), If I tweak the reflection ( drop it to 0.300) its looks ok but than Its loses the quality of glass.

I notice Any flat surface or objects with reflection materials, where its faces direct to the HDRI, its gets full/direct reflection of HDRI ( that is the issue).

maybe you have more experience with that sort of issue.

please say something if you know something.

regards

Last edited by dubai3d; 06-11-2012 at 07:13 PM.

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# 5 06-11-2012 , 07:35 PM

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That's what I thought, material tweaks are needed. Standard Maya materials aren't suited for glass right out the box because the reflectivity is pretty constant regardless of the viewing angle, extra nodes are needed to simulate Fresnel reflections (like sampler info node), or you could use the mia_material_x, it behaves more realistically and even has a Fresnel reflections checkbox. Is there any reflection blurring on the phong/blinns? If not, then I can see why the reflections look crisp and strange.

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# 6 06-11-2012 , 08:13 PM

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you Right GenT,

The Maya materials are not really good for glass. Here after bit of tweaking the reflection I got this newest update Image, but still doesn't looks like glass. I need bit more work on it.

Mia materials are good as you suggest, I'll Try with Mia materials. I know you are good in info sample connections,

Gen if there is any sources( link, tutorials....etc.) related to this subject please forward or mention, so I can follow the links.

thanks again

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# 7 06-11-2012 , 11:25 PM

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Actually the mia_material has presets for glass, you could try one of those. If you have to use the Maya shaders then you could apply this method to their reflectivity channel.

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# 8 07-11-2012 , 04:13 AM

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Actually the mia_material has presets for glass, you could try one of those. If you have to use the Maya shaders then you could apply this method to their reflectivity channel.

Originally Posted by GecT

Thanks for your share! Is it your blog?
How many methods to make glass in maya?
i'm a very beginner and i think there are some below ways:
1. use mia_material and preset to glass
2. use mia_material and use fresnel reflection checkbox
3. use dielectric_material
4. use blinn material and increase transparency value and decrease reflection.
please share some advice
Thanks!

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# 9 07-11-2012 , 06:44 AM

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Yep that's my blog.

I'd say 1 and 2 are the same deal, the glass presets use Fresnel reflections.

Using the samplerInfo node and a ramp(linked above) to control the blinn's reflectivity is another way but I don't see much point in it if you're using Mental Ray, the mia_material_x is more realistic and extremely versatile. I'd rather avoid the hassle.

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# 10 07-11-2012 , 08:23 AM

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Hi guys,

Yeah you right gen. maya mia-Materials has good preset glass (thin, thick, frozen....) so I used Mia_Materials with preset glass thin.

I'm getting bit tired of changing so many materials, so i can not see my error any more. maybe you can help me out.
this is the last render, what do you think Guy's? looks like a glass?

regards

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# 11 07-11-2012 , 08:26 AM

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I may need more reflection on the glass, but the mia_material_x1 reflection is on highest (1.0).

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# 12 07-11-2012 , 08:48 AM

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It's look good to me. If you need more reflection on the glass i think adjust BRDF can solver this issue

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# 13 07-11-2012 , 09:34 AM

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@duyquyen

Good Point, I'll try this option.

regards

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# 14 07-11-2012 , 11:34 AM

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its already on. there is no much think I can change, I tweak little bit of BRDF but seem nothing changed.

here is the render, that is what I can get so far. but it looks ok, much better than before.

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