leather chair WIP

[peterguthrie]

can anyone help me with a leather texture? I always struggle with leather. Reference attached. Currently the material is very simple, glossiness 0.6 and a low amount of non fresnel reflection (20). The modeling and bump maps are pretty detailed though.

Should there be fresnel or falloff reflection? multi layered reflections? mapped glossiness?

thanks!

[maru]

My guess:

lower glossiness

higher reflectivity

lower fresnel IOR

and lower diffuse level for better contrast

You can even set diffuse to 0 for testing, adjust reflectivity to look nice, and then enable diffuse and experiment with it.

[daniel.reutersward]

Hey Peter!

Nice chair!

I tried to match the reference (except the bitmap) and got this result. I´m by no means an material expert.

I attached the render and the material settings, hopefully it can help!

/Daniel

[Juraj]

I also think fresnel (or curve imitaing fresnel in fallof of either blend mat or reflection slot) should be used.
The no-fresnel kind-of works in the first angle, but shows the drawbacks in the second, where it "glows".

Once again, that's impressive chair !! Did you photoscan it or it's sculpted ? Great design too, reminds me of this one chair I can't find name of !

[Ludvik Koutny]

For leather, i would definitely use fresnel. But it is a bit rougher than plastic, so i would use say 1.9 to 2.5 values...

Also, mapped glossiness works quite well for leather.

I did some tests, which i think look alright. The problem of leather is that perception of it's glossiness is often biased by how large is the light source it reflects. So i did two versions... day and night. It could be perhaps even more reflective, but it's possible to tweak that. Also, i do not have so pronounced texture on my material, but i believe that is just a matter of finding a good one :)

You can PM me your mail so i can send you the scene with material.

[peterguthrie]

thanks for all the great input! this is where I have got to..

set fresnel to 2, bit more reflection, mapped glossiness, and I worked on the displacement/bump a bit more

Juraj, isnt that the Jetson chair (or a variant) by Bruno Mathsson?

[Juraj]

It is ! Hah, thank you, I didn't know either of those names. Well that's start, now I can model it.

About the new material...I don't know. The reflection is very flat, it's missing the "peak" from photography. Imho if fresnel is used, there is not much reason why not to keep reflectance really high.
It seems to be too "shiny" (low value of glossy slot, hate this backward terminology of 3D), somehow it should feature either layered polished reflection or work the fallof in glossy slot. But that doesn't mean I can create convincing leather :- D

[peterguthrie]

It is ! Hah, thank you, I didn't know either of those names. Well that's start, now I can model it.

no probs.. I usually try twitter when I come across a chair I dont know, in the past that was quite often, but these days i'm getting quite good at identifying furniture (becoming an unexpected side interest/hobby!)

[Ludvik Koutny]

It starts to look quite good. I would not be worried to put a bit more contrast to the glossiness map, perhaps also slightly more contrast to the diffuse map, if there's any, and maybe drop bump/displacement strength down by about 20-30% :)

[maru]

This leather still looks strange... As if it was wet or translucent. I did some tests too and it's extremely hard to make leather look good in different lighting situations. I ended up in a situation where very subtle changes in reflectivity or glossiness would have great impact on realism. Here is my conclusion:
A) you either make material with very low IOR like 1.2 and higher reflectivity (1 or so)
B) or you make it with IOR 2-3 and lower reflectivity (0,3-0,4)
But I still don't know which one is closer to reality. Guess there are different kinds of leather. The only leather I can find in my room is the band in my watch and it looks more like situation B. :)

[racoonart]

Since I'm currently sitting in my leather chair (oh I love that thing!) I had a closer look and it's more like two layers of reflection, a very very blurry one and a little bit sharper very subtle one blending in. I guess it's the coating that makes this effect, but I tried a very fast more "car paint"-ish approach (sorry, it's neither lit very good nor are the textures really useful, but anyways..)

[Coronaut]

Hey, here is complete scene if you want to check out materials of course if you like what you see on preview.
Model isn't something, texture is from wikkelso chair i did, but i did add another texture for wear and tear and highlights(that white patch) didn't wanted to do all from start.
Anyhow, painting highlights, glossiness is way to go.
Changed light setups on every image to see if it's universal.
Last 2 images are to see what are reflective/aniso properties it should have almost clean reflection(if leather is shiny from butt rubbing :D) but should disperse.
Anyhow i think you did good job on that last revision.
Please ignore fact that texture isn't from this model and totally inadequate(stretched, warped...)
cheers!   

[peterguthrie]

Did a bit more work on it, and added a white leather version (the white leather is crap, please ignore it material-wise!)

http://www.peterguthrie.net/blog/2014/3/sigurd-ressel-falcon-chair

i made the reflection map a bit more contrasty, and lowered the ior to 1.2 as suggested. I know its still form perfect, but i need to stop messing about with it now! thanks for the help and suggestions

[Juraj]

Those are awesome :- ).

And congrats to your modeller. I need to ask mine to step up the sculpting :- )

Enjoying the 25k px texture ?

[peterguthrie]

such massive textures are almost always overkill for me tbh!

oh, and thanks!