[gb_astro]

Originally Posted by CJ

Hi gb.
It's one of these
http://www.bintel.com.au/Accessories...oductview.aspx
I'll try it Barlowed. Thanks

I checked the mirror clamps and they are really not tight. Possibly a bit loose.

Cheers

I don't think that Orion collimator is going to work with a barlow.
The target for the return beam has to be in front of the barlow.
With your one the beam will be going back through the barlow again messing up the mirror centre spot shadow pattern (I think).

https://www.cameraconcepts.com/barlowed%20laser%20collimation.pdf

(Looks like you have to copy/past this entire line to get the link to work)

gb.