APM 2" Newtonian Coma Corrector and 1.5x Barlow Lens

APM Coma Correcting Telecentric 1.5x Barlow Lens, 2" barrel size

by the well known physicist and optic designer Philipp Keller

A few years ago APM Telescopes introduced the coma-correcting 2.7x Barlow designed by Gerd Düring, which enjoys great popularity.

New design

When more and more customers asked for a 2 inch version with a smaller magnification factor, APM Telescopes let the well known physicist and optical designer Philipp Keller calculate a new 1.5x Barlow lens.

All of today´s knowledge was incorporated to optimize the optical design. The telecentric design prevents that the distance has to be individually adjusted for each eyepice. Just insert the eyepiece into the optional 2-inch receptacle adapter and automatically have the optimum distance.

Large Backfocus

As already for the Barlow by G. Düring, the design was calculated to yield a large back focus, in order that it can be used as an optical glass path corrector with coma-correcting effect combined with binocular viewers.

The large back focus allows the use of an off-axis guider + filter + CCD to take photographs with full format chips.

Advantages and features of the Barlow lens

magnification 1.5 x

coma correction also for fast Newtonians

M54x0.75 male thread and M48x0.75 female thread (eyepiece/CCD side)

telecentric design with 4 lenses

works as optical path corrector 1.6x for bino-viewers

large imaging field for full-frame format chips

working distance from the M48x0.75 thread to the sensor position: 95 mm for perfect results

Safety informations: PDF Download