I`m trying for quite a long time now to get a curtain that lets nothing through except light. But.. i failed

[Link to i227.photobucket.com]

this is the only thing i can get.

but thats not it!

As you see.. the right curtain is white cause of the sun but the left one isnt o0 and the light (vray sun) comes from upper left as you can see by the way the light goes on the floor. and final strange thing i cant figure out why is: the right curtain is visible on the reflection of the floor but the left one isnt.

can someone give me helpfull directions? or solutions? i prefer directions cause i really want to learn!!! but hey. help is help

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