Skylabs Cheshire Eyepiece
Accurate Collimation tool for Newtonian Telescopes
The collimation (alignment) of the mirrors of the telescopes is extremely important for visual observation. In the case of really fast telescopes (focal ratio < 5) and astrophotography, the collimation becomes critical.
The Skylabs Cheshire Eyepiece helps align the optical axes of the main mirror and the secondary mirror of a Newtonian telescope. Unfortunately, traditional Cheshire eyepieces are quite subjective and collimation becomes a challenge as they are not able to achieve the precision required for astrophotography and relatively fast telescopes (focal ratio < 5).
The Skylabs Cheshire Eyepiece relies on a reflective spot perfectly centered in the main mirror of the Newtonian telescope and a reflective circle at the edge of the Cheshire eyepiece. The image of the circle is reflected several times by the mirrors of the telescope providing an incredible objective and accurate telescope collimation.
Single beam laser collimators are relatively affordable and easy to use. Unfortunately, they can not help to correct the off-axis position of the secondary mirror or ensure the collimation of the surfaces of both mirrors. While the laser collimator really helps to speed up the process, in order to ensure the perfect collimation between the two mirrors, a Cheshire is always required.
The mirror spotting template and center spots are also available for those mirrors without a center spot. Select the right size of your spot and template. Request the small triangle for 1.25” Cheshire eyepiece or the big one for 2” Cheshire. Obviously, if you have a 2” focuser a 2” Cheshire eyepiece is highly recommended.
Each order includes:
- Skylabs Cheshire Eyepiece
- Quick Guide
Template and center spot stickers are optional. The telescope, mirrors or other elements shown in the pictures are not included.