Hi,
I am posting this also to Refractor and Telescope making boards. After having only refractors for some time I bought a used 11 inch Newtonian for deep sky work and set to learn to collimate it. The Menard book says that refractors can be collimated using the Cheshire EP, that in ideal collimation two little donuts will exactly align when the cap is on and the Cheshire is illuminated. So I got curious and guess what, I tried my AP130 and saw the two little donuts, exactly atop one another. I tried my TV85 and got two donuts side by side, and on a TV 102, found three donuts which partially overlapped. The AP is the sharpest telescope I have ever viewed, so I believe this does reflect an accurate assessment of the collimation. However, the Televues have no means to collimate, and their images are pretty darned sharp too. Ought I take this up with Televue, (especially as the 102 is in warranty)? Is this a reliable means of assessing a refractor?
Ciao
Robert Howe
I am posting this also to Refractor and Telescope making boards. After having only refractors for some time I bought a used 11 inch Newtonian for deep sky work and set to learn to collimate it. The Menard book says that refractors can be collimated using the Cheshire EP, that in ideal collimation two little donuts will exactly align when the cap is on and the Cheshire is illuminated. So I got curious and guess what, I tried my AP130 and saw the two little donuts, exactly atop one another. I tried my TV85 and got two donuts side by side, and on a TV 102, found three donuts which partially overlapped. The AP is the sharpest telescope I have ever viewed, so I believe this does reflect an accurate assessment of the collimation. However, the Televues have no means to collimate, and their images are pretty darned sharp too. Ought I take this up with Televue, (especially as the 102 is in warranty)? Is this a reliable means of assessing a refractor?
Ciao
Robert Howe
Robert Howe
Wilbraham MA
TeleVue 85 f/7 // Astro-Physics Traveler 105 f/6 // Astro-Physics 130 f/8.35
Coronado 60 DS
"Scopes, Brains and Wisdom--but no Beauty"
