First test with Maya

[Hamburger]

Pretty impressed so far. I think the gi solution is very natural and so easy to setup. Noisy, but if we throw some more power at it, I'm sure it'll clean up when distributed rendering comes along. But for now, even though this is very simple scene, it is easier to use than many other renders on such a scene and faster to get nicer results.

There is something odd going on with the daylight system too, I'm completely unable to get a nice clean, sharp shadow in such a scene like this with the coronaSun pointing indoors. I'll have a look more closely at some other settings but there is something strange going on.

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I'm also working on a material conversion script. so far I've got lambert working, it's just a long process to add more materials! :)

[Hamburger]

Here's test number two. Initially a SketchUp scene, I used a convert "VRay Materials to Corona materials" script on this scene.

I can't get my script to do bump maps yet, and VRay and Corona differ on what is anisotropy it seems but I hope to improve it more.

There should be a direct sun lighting half this room but I don't think it works yet. :)

[haggi]

Wow! I wasn't aware that someone can do something really nice with the mayaToCorona plugin ;)

Sun lighting should work, at least in one of my exremly complex scenes with a plane and a sphere.

[Ludvik Koutny]

One of main problem of CoronaToMaya is that it uses wrong developer defaults. In this case, if you have glass in windows, which do not have caustics disabled (that's what happens with correct defaults), then sunlight will simply get clamped by MSI solution.

[Hamburger]

Sun lighting should work, at least in one of my exremly complex scenes with a plane and a sphere.

Haha! When the sun option in render globals is activated, corona changes the sky color just fine. But I was expecting something like vray and mental ray sun + sky system where I could produce sharp shadows from the sun (see attached which is VRay4C4D render). No matter the size or multiplier of the sun, or any number of parameters in environment settings, I'm having some trouble getting a nice sharp shadow from the sun. 

I was wondering;
Is the corona sun built into the renderer where the maya/corona directionalLight is only used an aiming guide?
Or is it expected to use the maya/corona directionalLight directly as a sun source?

One of main problem of CoronaToMaya is that it uses wrong developer defaults. In this case, if you have glass in windows, which do not have caustics disabled (that's what happens with correct defaults), then sunlight will simply get clamped by MSI solution.

I did not know this. For the second scene I think it might be avoiding this problem though as to the right of screen, there is no geometry and that is where I had the sun pointing through.

[haggi]

From the directional light the color is used as well as the "Sun multiplier" value in the directional lights corona settings.

[Hamburger]

What was confusing me is that when Corona creates the "sun" in Maya, illumination checkbox is off by default so it is not doing anything.

Edit: Hmmm....turning on the corona sun in Maya doesn't seem to do much at all, neither does increasing the strength.
I mean here is the same scene rendered in 3DS Max (minor difference in materials, but overall both 3ds max and maya versions are using preetham and sun is in the same position and same exposure) yet the difference in lighting quality is very apparent.

[haggi]

I'll have a look why it is not using the attributes.

[Hamburger]

A kitchen scene with .34. The noise is still very high for me, but I have a slow i7 950 and after 12 hours of rendering it is enough!

The quality of light with Corona is unmatched!

[haggi]

Nice! But 12 hours is quite long. Did you use portals?

[Hamburger]

Yes, I used portals, but the noise came from glossy materials - not the light.