Coma makes stars look like blurry comets whose tails point out radially from the center of the field. The faster your scope's speed, the worse the effect. All parabolic mirrors used in Newtonian reflecting telescopes are limited in field sharpness due to coma. Even a perfectly made 13" f/4.5 parabola has only about 0.1 degree diffraction limited field.
Previous attempts to correct for coma have been limited in usefulness. Some correctors were designed mainly for astrophotography. Dedicated coma correcting eyepieces were another approach. However, these were limited to 50 degree apparent fields and would orphan your existing eyepiece collection.
Developed in 2010, this model can make an f/3 mirror act like an f/12 without a Paracorr. Essentially diffraction-limited across the field, it makes the new breed of f/3-f/4 "ladder-less" Dobs possible, and superior in terms of convenience, field-of-view and optical perfection when using top quality mirrors.
The Paracorr Type 2 allows separating the optical assembly from the Tunable Top and using it with Tele Vue imaging system components to permit use with SLR and CCD cameras. APS size formats 27mm diameter are recommended to minimize field vignetting. Ideal for mirrors as fast as f/3.
Paracorr is easy to use. It slips into your focuser, just like a Barlow. To minimize focuser in-travel, due to additional length, a mild 15% Barlow effect was designed into Paracorr to effectively push the focus out. Paracorr is recommended for use with all Tele Vue eyepieces because our Plössls, Radians, Panoptics, Naglers and Ethos achieve higher levels of aberration correction than competitive models. However, Paracorr is also compatible with other eyepiece makes.
Specification:
TeleVue Paracorr Type II coma corrector:
- Bruikbaar voor 1.25 en 2 inch oculairen;
- Door middel van acht standen is altijd de meest ideale correctie in te stellen;
- 2 inch naar 1.25 inch reductie adapter;
- Intern schroefdraad voor 2 inch filters;
- Ingebouwd 1,15x barlow.
- Correction Optics Type
- Coma Corrector