Are there any changes in Autodesk Physical Mat. Interpretation in Corona HF1?

[Byteman3D]

Hi,

I'm working on a medical animation and some of my materials were Autodesk Physical Material. We've had a weeks break in the project so I decided to upgrade all  PC's in the office to hotfix 1.
After a week, I have opened the latest files of the project and to my surprise, my reddish transparent material was simply frost white glass. Actually all my Physical materials have become somewhat different. Skimming through dozens of copies and backup files, I couldn't find a single max file with my original reddish glass material. I decided to look at the files on the only PC that doesn't have the upgrade just in case there might be some backups and the only scene file on the computer opened just fine.
I took the files to the other desktops and that is when I realized its about the upgrade.

You can see in the attachment both versions of the same material.

Luckily I 've had a PC that I haven't yet updated. Is there a simple workaround  option button to revert the Physical Material effect to the previous version.

I needed the physical material for seamless fades between different material effects and the material properties are already animated.That's why switching to some other material is risky.


Edit: The Scale parameter under the Scatter Color seems inoperational in hotfix 1. It renders as if Scale value is set to 0.

[pokoy]

What you say could be perfectly the case, however maybe it's only now correctly respecting the subsurface value. It's set to 0.0 in both screenshots, still it uses scattering in one version while it doesn't in the other. What happens if you set sub-surface to 1.0?

[Byteman3D]

Scatter value had no effect in both versions, so I checked each parameter one by one. Transparency is also set to 1.0 and that seems why Scattering has no effect

SSS and translucent  materials  (may be some transparent materials, too) really baffle me at times. I tried to achieve a similar color with the new version. Red Scatter color displays a complement color (Like cyan) and cyan shows a reddish tint. This used to be like this in some of the ancient max materials, too, (like raytrace material) so I used to think it is something about the actual physical behavior of those materials.

I avoid using these not just because they are CPU intensive but hard to control.

[Avi]

Hi,

There were some changes in how Autodesk physical material is evaluated. We have this logged in our system and it will be reviewed by our devs.

(Report ID=CMAX-1289)