Grass material

[medzo]

Hi!

Why Vray renders grass so much more realistic than Kray? This is especially noticable with close-ups.

Both renders are from Vray, I can't get even close with Kray. Any ideas?

[Janusz Biela]

You can make the same in Kray. I do not see any problems.
The only one difference is: in V-ray you have special shader which simulate fast SSS.
But I doubt it is used in these renders (slow render).
Rest depends form user skill.

[medzo]

Well, first render shows double sided material, second has activated translucency inside standard material (hybrid mode+ greenish translucency color).

With Kray I was getting close with LW translucency shader pluged into diffuse shading, but it is painfully slow (150x200px took 45 minutes).

Don't get me wrong, with Kray I can make grass that is quite nice, but it is just not the same level of quality like Vray.

This is what i get straight from Kray

It can be improved in post production, but I dont think it reaches Vray quality

[3dream]

So which image (top or bottom) is VRAY. There are things about each that I like. Just curious.

[Janusz Biela]

So which image (top or bottom) is VRAY. There are things about each that I like. Just curious.

First topic has two images from V-ray.
Medzo I think you should concentrate more with better surfacing (specular or reflection) + better light.

[CHRIS.PI3]

Well I don't see any difference.Kray grass seems equal if not better.The lighting in the vray scene makes the difference.

[Keraressi Abdelkarim]

Easy in this sample scn u can acheive any render from vray with kray 2.5 and u can do more quality go pls take a look on janusz render he is thebest . With his skill and his crazy surfaces no vray artist included alex romain and so on cant produce janusz biela surfaces his own surfaces and his knewedge. Also u can acheive any photorealistic with kray.

[Janusz Biela]

Actually, problem with grass and leafs is very wide.

- problem with SSS (nobody even try simulate on big scale this effect)
- leaf material is one of the difficult material for simulate
- amount of physic in leafs is huge (SSS, transparency, reflection, bump, etc)
- the only way to render grass/leafs property is simulate it by mix of specularity, reflection and translucency
- in Kray we have only "simulation" of translucency from Lightwave is not that good as Fast SSS Shader in V-ray (I mean fast transport of light inside materials) this is only one missing part in Kray.Rest you can easily do by Nodes - for example: Double Translucency which is very important for leaf )not for grass!)
- very important is shape of leafs (it must looks naturally) Not too thin not too thick, not too curved not too straight. Random of seed by Instances must be also done very well - no repeating feeling.
- post process the top one (Yes! renders from V-ray also are ugly and only good post process can handle it)
- Sometimes nice looking close-up of grass doesn`t mean it must looks great in exteriors scene...sometimes is just artist expression with post process.
- generally, I think, there are just a few people who knows how to render property grass and leafs...
- because we have all tools to render grass/leafs (except this unlucky shader for fast SSS) everything depends from our skill
In free time I will try continue this topic because personally I also get mad about this material simulation

[medzo]

Nice!

Could you show us raw render without post?
And material setup, please?

[Alexis]

Yes, very good render

[brainpolka]

My take on the grass close-up. With some DOF it will look sexy anyway

The hard part is to make it look real on a big scale.

[Janusz Biela]

I was waiting for refreshing post
Here my tests (still in queue some ideas). Problem for me is that grass need quite strong post process and an idea how to show the render. It must be strong Dof, close-up, kind of strong saturated post...I do not like. Anyway in free time will render some new views.

[brainpolka]

Haha yes. This will be an ongoing process for me now. Find the right grass!

[Janusz Biela]

Try with this model from my renders.

[brainpolka]

Thanks!