I am selling my Howie Glatter 1.25" Laser Collimator which comes with both the 1mm pin point aperture and Holographic Concentric Ring attachments.
The Concentric Ring pattern is specifically beneficial for Cassegrain and RC telescopes where the effect of the pattern is sometimes seen on the mirror exteriors because the light from the laser is extended over less of an area and is therefore brighter than the standard square grid pattern. It can also be used to project the internal baffle ring appearance on walls for primary alignment. I used it to set up my RC scope, where it allows precise primary mirror alignment with the Ring attachment, and secondary/focuser alignment using the 1mm pin point aperture.
Originally purchased from Bintel, where a new one would cost you $259. I am asking $160, plus $10 for shipping to any Australian address, for my very lightly used Howie Glatter Laser Collimator as described above. Note that this Laser Collimator has never been dropped, and is still perfectly aligned. Photos are attached. Comes with a plastic protection tube for the Laser.
If your interested in this useful tool please PM me here on IIS. Thanks for looking.