Shadows through cloth -- 'affect shadows' problem?

[camfran]

Another problem which has been perplexing me:

 

I'm trying to set up lights for a covered courtyard scene. I have the cloth material a bit grey on Refractive so that some light comes through the cloth canopies. I also want the support wires to then lay a darker shadow, so there'd be a medium grey from the cloth, and darker stripes from the wires.

 

However i'm having trouble -- it's either All or Nothing, as in the images below. It's the 'Affect Shadows' check box which controls the on/off behaviour, i've found.

 

Any ideas how to reach a happy half-way house situation?

 

Many thanks!

[camfran]

... it seems somehow connected to the GI -- when i turn GI off, i get both semi-shadow from cloth and also the darker shadow from wires (with 'Affect Shadow' ON).

 

Also i just saw that when i turn GI down to 0.2 i still get the effect ('Affect Shadow' ON) -- but the earlier test was only at 0.8. Hard to believe it would get blown out by such a low GI?

 

Strange... any ideas?

[ShaunDon]

This is totally a shot in the dark and a total work-around if it even works -- but have you tried turning refraction off (to black) and changing the visibility in the Max object properties? I do this for quick exterior glass a lot of times to just get a hint of reflection without having to calc refractions, but it might be a solution in this case as well.

 

First I'd try boosting the refraction depth -- anywhere from 20-50. That often times has a great impact on how much light filters through the material and may provide a more accurate effect.

 

Good luck!

[Trick]

Have you tried mapping the opacity (not refraction !!) slot ?