The Cheshire collimation device is the simplest, most intuitive tool for adjusting the primary mirror collimation in a Newtonian telescope system. In addition, the Cheshire is relatively insensative to poor fit in the focuser since many, especially inexpensive focusers are oversize.
We suggest using the Cheshire in conjunction with Farpoint's single beam laser collimator. First use the laser to adjust the alignment of the secondary mirror, then adjust the primary mirror alignment using the Cheshire. Using this technique, your scope can be aligned in under two minutes!
Farpoint makes the Cheshire in 1-1/4 and 2 inch sizes to accommodate both common focuser sizes. Each Cheshire is machined from aircraft grade aluminum on a precision CNC lathe to exacting tolerances. They are then polished and hard anodized for a superior appearance and durability. The grip ring is knurled for a sure handhold.
Each Cheshire includes four primary mirror marking triangles and detailed, illustrated instructions. An alignment template for applying the triangles onto mirrors up to 12.5" diameter is also included. The template has metric sized marks for imported telescopes as well as English measurements. For those with mirrors larger than 12 inches, Farpoint offers larger templates for sale or a free pattern download from their web site for those who wish to print their own.
To use the Cheshire collimation system, a reflective triangle center "spot" is applied to the primary mirror in a one-time application process. Once applied, all one needs to do in order to align the primary mirror is insert the collimator into the telescope eyepiece holder, look through the sight hole and adjust the primary mirror collimation knobs to center the reflective triangle in the image of the white ring projected by the collimator. The system works in daylight or and night with the aid of a dim astro-flashlight aimed down the telescope tube.