Hi Brian,

thanks for your reply! I like to do a laser experiment with Thea Render. For the laser i
would like to use a spot light aiming at the center of the mirror. The goal should be
that the reflecting light beam from the mirror is then parallel and only the parallel
beam will be seen in the image.

I guess i will have also to adjust the light parameters, from the spotlight several
times to get the desired look.

But first i must know how to draw that simple surface mirror with it's correct
curvature angle in order to do the test. :-)

P.S. according to this Thea tutorial this for getting thicker parallel light beams.
And the author shows a picture as proof that this works. He describes also other
techniques, but i like to try out this one. I could ask also on the Thea forum,
but i don't know if there are many MoI users or if the author modeled this
in another NURBS or poly package...

Regards
Stefan