I was trying to do a laser collimation on my homebuilt 10" refractor setup (bought the lens) with mixed results. I verified the beam was exiting the front of the scope very near the center of the lens, and the reflected return beam went into the focuser. But when I racked in the focuser, the return beam would be offset. My guess is I have some offset in the placement of the focuser 
But the funny thing was the laser light would scatter inside the thick glass surfaces, but in some places in the lense, the scatter would simply dissapear. I know there is some fluid between the glass surfaces, but I thought this was a very thin separator, and not a thick layer. I don't think there is an air space inside, but I could be wrong. Anybody have some thoughts ?? I also tried it with a high power green laser, same results.
Note the bright spots are where the light enters and exits the glass.
David Simons
But the funny thing was the laser light would scatter inside the thick glass surfaces, but in some places in the lense, the scatter would simply dissapear. I know there is some fluid between the glass surfaces, but I thought this was a very thin separator, and not a thick layer. I don't think there is an air space inside, but I could be wrong. Anybody have some thoughts ?? I also tried it with a high power green laser, same results.
Note the bright spots are where the light enters and exits the glass.
David Simons
Attached Image:
David Simons
