Moving from Vray to Mental ray. creating equivalent shader

[ndeboar]

just eye balling it, i would say:

50% diffuse, 50% reflection. Make the reflections 70% glossy/blury (like, cone angle of about 100 degrees).

And you need a nice noisy bump map too.

But, that's probably not of much use :)

[fael097]

just eye balling it, i would say:

50% diffuse, 50% reflection. Make the reflections 70% glossy/blury (like, cone angle of about 100 degrees).

And you need a nice noisy bump map too.

But, that's probably not of much use :)

hmmm yea thanks for your help, but that didnt work out at all, the result is totally different than what i expected, i have a really bright environment, like colorful bright sky, clouds, things that will reflect a lot, and that cannot get mirrored on the material, i have to set real low reflection and glossiness has to be like .4, .5 or the sunlight will not spread on the material surface, it will reflect the sun. its really weird and tricky, so if anyone can, i dont know, create a UFO like object to test the reflections, add a sky HDRI to simulate the environment and test material settings, that would be a huge help. i can also provide a scene if someone wants to help!
thanks ppl

[ndeboar]

you notice when the sun hits the fuselage, it spreads its light, reflecting a nice way, not glossy. but when i reduce the glossiness in mental ray, the reflection goes away. and if i increase reflection, it also reflects the environment, what i dont want at all!!

Ok, just a few things. That highlight on the fuselage is a glossy reflection, eg what your seeing a simply a blurred reflection of the surrounding environment, the hi light being the sun. The environment will always be reflected in the material if your going for realism.

[fael097]

Ok, just a few things. That highlight on the fuselage is a glossy reflection, eg what your seeing a simply a blurred reflection of the surrounding environment, the hi light being the sun. The environment will always be reflected in the material if your going for realism.

yea, but lets say 0% is totally opaque and 100% is totally glossy, the fuselage should be about 45% glossy on MR with my tries. the only problem is the reflection rollout, if i put a higher value, to reflect more the sun, the environment also starts to get reflected too much, that makes the material looks too blue, and if i set a lower value, the sunlight will disappear like it was too weak, you know?

[azazel]

You seem to have a lot of overbright (pure white), and oversaturated highlights in your scene (look at the sky, the wings...) The photo you posted, not so much. You can combat that by using Exposure Control (preferably "MR Photographic Exposure"). It takes a bit of work to get decent results, as there's a lot of settings to try, unless everything is built in real-world scale and units, but it's worth it - you can get much more natural looking image. In Vray, I'd just change the color mapping to "Exponential" and be done with it ;).
Second thing, the plane on the photo has much darker diffuse (color map). You have it much brighter, and that changes the way you preceive the highlights.

Now, do you use "Arch&Design (mi)" shaders? If not, I highly recommend it. Among other things, you can set your own reflectivity function curve. Other things to try are using faloff map in the glossiness slot, and using "Highlights+FG" only option to get rid of the unwanted sky reflection.

Just some ideas to try ;).

[fael097]

You seem to have a lot of overbright (pure white), and oversaturated highlights in your scene (look at the sky, the wings...) The photo you posted, not so much. You can combat that by using Exposure Control (preferably "MR Photographic Exposure"). It takes a bit of work to get decent results, as there's a lot of settings to try, unless everything is built in real-world scale and units, but it's worth it - you can get much more natural looking image. In Vray, I'd just change the color mapping to "Exponential" and be done with it ;).
Second thing, the plane on the photo has much darker diffuse (color map). You have it much brighter, and that changes the way you preceive the highlights.

Now, do you use "Arch&Design (mi)" shaders? If not, I highly recommend it. Among other things, you can set your own reflectivity function curve. Other things to try are using faloff map in the glossiness slot, and using "Highlights+FG" only option to get rid of the unwanted sky reflection.

Just some ideas to try ;).

hey man! thanks for the tips! about the overbright youre absolutely right, i can notice by the darkness of the shadows comparing the photo and my render. i believe thats because of my skylight, and i'll just put a lower value into it maybe, and try what you said. actually the exposure will have to work, because the actual scene wont have skylight, this is just a test scene with a hdri for the sky reflection, a sky light and a sun. about the sky reflections, its not that i want to exclude them, i want it to look the more realistic possible, and it seems for me that reflecting on this material wont make it look real, neither totally excluding them, so im trying to achieve a good result in regular ways hehe
well i'll try some more and update it. thanks again!

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