TeleVue Paracorr Comacorrector, Type 2

TeleVue Paracorr Comacorrector, Type 2: comacorrector for parabolic Newtons

The Paracorr Type 2 is the standard among visual comacorrectors. It corrects parabolic Newtons to f/3 and increases the focal length by a factor of 1.15.

The Type 2 appeared when lenses of f/4 and faster became commonplace; the design was based on that generation of Dobson telescopes, where the original from 1989 had its limit at f/4.5.

Why a Newtonian telescope has coma

A parabolic primary mirror images only the center perfectly. Toward the edge, stars acquire a comet-like tail: coma. The faster the mirror, the smaller the sharp center; at f/4, that is only a few millimeters.

No eyepiece can fix that, because the error originates in the mirror. A corrector in the light path can, however. The Paracorr corrects the coma and leaves the rest of the image unaffected.

The adjustable top

Each eyepiece has its own optimal distance from the corrector lens. The adjustable top of the Paracorr has numbered positions; Paracorr publishes the correct position for each eyepiece, so that you are properly positioned after switching.

With the correct setting, the correction remains intact across the entire field and there is hardly any change in the focus.

Included

• Paracorr Type 2 with adjustable top
• Dust caps

Featured accessories

The Paracorr is the permanent partner of Ethos and Nagler eyepieces on fast Dobsons: especially with 82 and 100-degree fields of view, you see the edge, and therefore the coma. With the corrector, stars are point-like right into the corners.

For whom yes and for whom no

• ✓ Parabolic Dobson and Newton telescopes from f/3 to about f/6
• ✓ Owners of wide-angle eyepieces
• ✓ Who wants to regain the edge sharpness of their mirror
• ✗ Telescopes without a parabolic mirror
• ✗ Refractors and catadioptric systems

Specifications

You can find the complete product line for this brand at the TeleVue brand page.