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royter
11-19-2010, 09:54 AM
i dont have a big experience with the mi_car_paint_phen_x shader, i have been trying to tweak this shader wich is assigned to a clean car model. But the results are not convincing:
is there any guidelines, things to add to the shader, specific tweaks or workflows?

Dangertaz
11-19-2010, 10:31 AM
Is it a close up or a medium shot?

Can you post your WIP?

royter
11-19-2010, 07:56 PM
medium shot.
will post a wip asap

royter
11-19-2010, 09:16 PM
here is the wip renders:
http://www.youfile.net/download.php?file=db6059dfe46b0111409647fbcd8353ab

material settings:
http://www.youfile.net/download.php?file=f246886197924e8e35d2705a9be216da

Dangertaz
11-19-2010, 10:31 PM
I think it's too reflective.

Try .05 for Reflection Base Weight.

I don't think you even need flakes, they're too small to see at that range. I would just set their color to black and ignore them.

Flakes will be massed together at that distance and handled by the Secondary Specular. Try Spec Sec Weight: .6 so it's a bit more obvious.

You may wish to darken the color slightly so we can read the forms more easily. No flat, blown-out whites.

royter
11-20-2010, 12:54 AM
I think it's too reflective.

Try .05 for Reflection Base Weight.

I don't think you even need flakes, they're too small to see at that range. I would just set their color to black and ignore them.

Flakes will be massed together at that distance and handled by the Secondary Specular. Try Spec Sec Weight: .6 so it's a bit more obvious.

You may wish to darken the color slightly so we can read the forms more easily. No flat, blown-out whites.

Her is a version with diffuse darkened, flakes fixed

http://www.youfile.net/download.php?file=00986acd85641045a43e78b94a27af41

still not convinced!

Dangertaz
11-20-2010, 02:05 AM
I think it's improved but I'm not convinced either. I think with that sIBL environment we will need to see the car with the background and with a bit of glare added in post. It's so out of context it still looks a bit cartoony.

Sunny sky environments are tricky, they almost always look fake to me. I think it takes a bit of glare or bloom to really sell it.

royter
11-20-2010, 04:04 AM
I think it's improved but I'm not convinced either. I think with that sIBL environment we will need to see the car with the background and with a bit of glare added in post. It's so out of context it still looks a bit cartoony.

Sunny sky environments are tricky, they almost always look fake to me. I think it takes a bit of glare or bloom to really sell it.

this is what i am working on right now.
because of the lack of a descent glare shader in MR4Maya, i am using my own technique where irender a pass with the mia_sky as the environment, lower the rgb units and boosting the sun intensity and use a black material with only fresnel reflection and comp it an AA and add glow.
http://www.youfile.net/download.php?file=67a12a00e1352fe4caf9faffe9ebff03

still not convinced, the car in MR4Maya must already look realistic without bllom and chromatic aberration.

Dangertaz
11-20-2010, 04:55 AM
So for the glare pass, everything has a black material applied to it. The sun intensity within the Phys sky is pumped up (how high generally?). This pass has the default Phys sky as the environment, as opposed to a detailed HDRI. Where/when are you lowering the RGB values?

The Ford focus on this page looks really good, and I don't detect a lot of post work. It was done in with MR in Max but it should be replicable in Maya. There were some more shots of it but I can't remember what board I saw them on...

http://www.dmmultimedia.com/3dtips_11.htm

Can you post some examples of the look you are trying to achieve?

royter
11-20-2010, 05:07 AM
So for the glare pass, everything has a black material applied to it. The sun intensity within the Phys sky is pumped up (how high generally?). This pass has the default Phys sky as the environment, as opposed to a detailed HDRI. Where/when are you lowering the RGB values?


the material is a simple mia_material with only reflection turned on (fresnel with a 1.4 IOR or the closest IOR to a car paint, 40 or 50 for metal parts)

the mia sky has a 0.000010 RGB Unit conversion value, 1000 for the sun intensity.

the pass has the mia_sky instead of the hdri as an environment (the directional is placed carefuly to match the HDRI sun wich i erased in PS)

the lowering of the mia_sky RGB values is taking place only in this pass.



this the look i am tryong to get:
car:
http://www.autoblog.com/photos/review-2011-cadillac-cts-coupe#3413611

glare type:
http://www.moritzcadillac.com/db_uploads/2010_Cadillac_CTS_Sedan_107122_Black_1.jpg

glare in motion:
http://www.youtube.com/watch?v=GYb_28zRioM&feature=player_embedded#!

Dangertaz
11-20-2010, 05:26 AM
Gotcha. That's a lot of work. I really wish they would release a nice glare shader.

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