The Lacerta 4-element Barlow lenses are telecentric systems and offer superior imaging performance, even off the optical axis. This distinguishes them from conventional designs, where imaging noticeably deteriorates towards the edge. This is a major disadvantage, especially for planar objects such as the sun and moon. The Barlow lenses have not only high quality optics, but also exemplary internal blackening. This is very important, otherwise internal reflections would worsen the contrast, the lens edges are of course blackened. They do not produce additional chromatic aberration and are therefore our recommendation for apochromatic lens telescopes.

These barlows extend the focal length of the telescope by the specified factor, and also shift the focus further back. A special feature of telecentric barlows is the bouncing light exit, the distance barlow eyepiece/camera therefore no longer changes the extension factor, this is advantageous if further accessories such as a filter wheel are to be mounted in front of the camera.

The telecentric Lacerta Barlows are available with the extension factors 2x, 3x and 5x. All of them have a 1.25" socket with filter thread, on the eyepiece side they have a ring clamp.