How to project an image onto a surface

[buggy]

I was able to import your projector and test it. It appears that in my particular scene getting an image to resolve looks like it will takes a very long time if at all, so I don't think this will be practical.
I think I will have to try to apply the projection in post. It won't look as real but should do the job for my client's purposes.
I wonder if Otoy would be able to build a faster image projector . . .

Thank you so much for your help! I may tinker with the concept a bit more when I have more time.

[gueoct]

I was able to import your projector and test it. It appears that in my particular scene getting an image to resolve looks like it will takes a very long time if at all, so I don't think this will be practical.

i don´t get it; i am working with 3 x GTX 580 and it renders super fast. did you check" fake shadow"?

[buggy]

I don't get it either. In your scene the projection resolves almost instantly.
I tried importing the rig you created into my scene and it was blurry. The last time I left it for over an hour and it was still be big blur. I thought that perhaps existing lighting, etc. might be complicating things but even when I turned off all other lights (and no HDRI environment), and hid all other objects, it still is fuzzy. That makes me think it must be some global setting like scale settings. I get a message about the gamma and LUT settings of the file not the same as the system settings each time I switch between the two scenes. I always select "use the file's settings", but I jut tried adopting the system settings. Still no luck. The Fake Shadows option is selected.

Now I am intrigued! I'll keep playing with it. I would upload my scene except that my client wouldn't like that
I think I'll try stripping everything out of the scene and reimporting your setup to see what happens.

One small tip: the projection feature doesn't work at all in Direct Light mode. A few times I have forgotten to switch to Path Tracing and wondered why no light was emanating from the projector.

[buggy]

I found the key!

1) I stripped everything out of my scene and then merged your scene into it. Even then, the projection wasn't working.
2) I went through all of the Octane Render settings and compared the two scenes. There were a few significant differences such as GI clamp set to 1,000,000.00 vs 2.00 in your scene and diffuse depth at 4 vs 2, but even after changing these it didn't work (I never even played with these so the values must have been defaults).
3) I turned on ALPHA SHADOW. This did the trick! I suppose it should have been obvious. It would help to have documentation that clearly explains all the features

The images immediately resolved. However, for a reason I can't seem to find, they are much brighter and washed out than those in your scene. I have to drop their brightness to 10% of what they are in your scene to get the correct illumination. Also, your scene has a mystery source of abient light; even when I turn off both lights the scene is illuminated. There's no HDRI set up. How did you accomplish this?

[gueoct]

....... I suppose it should have been obvious. It would help to have documentation that clearly explains all the features

There is no obvious reason why "alpha shadow" should avoid that problem...
I totally agree: We need a proper documentation !!!
i have mentioned the lack of it so many times, already.
the most recent 3dsmax plugin help file came out April 2014.... !!!

[gueoct]

I....I suppose it should have been obvious. It would help to have documentation that clearly explains all the features

don´t worry; there is no obvious reason why "alpha shadow" should solve the problem.
i totally agree: we lack a proper manual !!! The actual manual version is from April 2014...!!!!

[buggy]

Thank you -- I don't feel so bad now

Documentation would be good to have. Until I upgrade Max it looks like I am at the end of the road for Octane upgrades since they are no longer supporting Max 2011.
I also see that Autodesk will be shifting to a subscription only plan next year. This will cost a lot more for people like me who upgrade infrequently. I have met many users in the past who would skip every other version, so overall I think Autodesk will be squeezing quite a bit more out of its users. I may have to investigate alternatives that also work with Octane such as Modo, but I don't think it has animation capabilities.

I think the difference in brightness was because I accepted the system LUT settings which were set to 2 instead of 1 (must be an exponential effect). But, even so it's not clear where the ambient light in your scene is coming from, when I turn off both lights.

[mark0spasic]

Thank you -- I don't feel so bad now

Documentation would be good to have. Until I upgrade Max it looks like I am at the end of the road for Octane upgrades since they are no longer supporting Max 2011.
I also see that Autodesk will be shifting to a subscription only plan next year. This will cost a lot more for people like me who upgrade infrequently. I have met many users in the past who would skip every other version, so overall I think Autodesk will be squeezing quite a bit more out of its users. I may have to investigate alternatives that also work with Octane such as Modo, but I don't think it has animation capabilities.

I think the difference in brightness was because I accepted the system LUT settings which were set to 2 instead of 1 (must be an exponential effect). But, even so it's not clear where the ambient light in your scene is coming from, when I turn off both lights.

White color is coming from enviroment, you can change color of enviroment under rendering/enviroment tab (key 8 on your keybord).