V-Ray and Corona

[LudvikKoutny]

nothing wrong with 1 being the limit for Corona. no refracting material on this planet actually speeds up light passing through (IOR<1) but if for some reason you need purple part of light bend ?left? and cyan part bend ?right? on a single poligon refractive plane than you going to have more luck with VRay.

I am a bit confused. I told you in my previous post that Corona can actually do IOR below 1 to which you have replied that it the color input indeed works, but it treats IOR<1 as 1/IOR, which is indeed the case, but I pointed out that I believe V-Ray is doing the same thing, is it not?

Also, when it comes to Abbe number (unrelated to the IOR issue), it's not that Corona is more physically based than V-Ray so it limits it. It's just that some of the developers decided to cap it at 10 because there are no real world materials with Abbe number under 10. He did not expect users would require that much artistic flexibility. Think of it being similar to energy conservation. For example in Mental Ray and Arnold it is possible to put HDR color into diffuse or reflection, and then the diffuse or reflection will end up glowing, and breaking energy conservation, while V-Ray makes sure to conserve Diffuse and Reflection in realistic ranges. But as I said, it's really just a UI limitation, feel free to report it as a bug/tweak and it will likely make it into next version.

In the meanwhile, if you need sub-10 abbe number in Corona right now, you can have it, just open curve editor, find your material, and assign Float Expression controller to the "dispersion" track:

This way, you can put any Abbe number there and it'll just work. Not very user friendly, but needing such an extreme abbe number is a rare case anyway.

[piotrus3333]

than you for the abbe trick.
VRay handles IOR<1 differently to Corona.

[LudvikKoutny]

than you for the abbe trick.
VRay handles IOR<1 differently to Corona.

That's interesting. Are we talking about Reflection IOR or Refraction IOR?

[piotrus3333]

That's interesting. Are we talking about Reflection IOR or Refraction IOR?

refraction

[cmjohncheng]

https://www.youtube.com/watch?v=1VFjOzz4mUo

since corona can render vray material, can we install vray(demo/without license), and use vrayMlt for material but render with corona?

[Nicinus]

I enjoy both engines, but for me the biggest draws to Corona are the lightmix interface and setup, the material preview and the material library...super handy when youre in a rush and quickly need rubber or something I dont have in my custom library. But being able to tweak lights right in the VFB is so great, and being able to bake those settings into the scene is even slicker.

I haven't looked at Next yet, but wasn't the intention that Vray 4.0 would have material preview and some form of light mixer in a new VFB as well? Were those plans postponed?

[glorybound]

I don't see anything different with the VFB post controls.

[Nicinus]

Maybe I'm mixing it up with PDPlayer or something but there was a video of a new framebuffer a while ago. Oh well, but what about the material preview?

[Ihno]

From what i heared at least the light mixer and the vfb compositing will come to vray. but they might be added a little later in a servicepack. I dont know about the material preview.