Recomended Cheshire

[beachbum]

Hi, I'm looking to get a cheshire and sight tube for my 8 inch newtonian and I was wondering which brand is most recomended and if its better to buy it seperate or combined, I'm not interested in a laser yet and I've used the film canister already but now I'd like something of quality.

Thank you

[Damo636]

I use this one, Astro Engineering AC656 Colli-Mate Deluxe eyepiece for collimating Newtonian and other telescopes

Slightly more expensive than the run of the mill ones but works well for me.

This will do the same job though and a little cheaper http://www.firstlightoptics.com/collimation/cheshire-collimating-eyepiece.html

[beatlejuice]

This is what I use from orion and it is also sold on this side of the ocean.

Orion Telescopes: Orion Collimating Telescope Eyepiece

Eric

[umadog]

If you really want something of quality, buy Catseye.

[beachbum]

Alright thanks guys, but is there a big difference between the brands? Or are they mostly the same quality?

[acey]

Any Cheshire will do, or you could even make your own. It's not a high-tech piece of equipment, though maybe some brands are more nicely machined than others. It doesn't matter if it isn't a silky smooth fit in the focuser - slop is not an issue with a Cheshire, as it is with a laser. As long as the cross-hairs meet in the middle it will work fine.

Just one little thing to think about, the Cheshire should ideally have the same f-ratio (length to diameter) as the scope. If it's too long and your scope is fast then you may not see the whole of the primary mirror. But your 8-inch is probably an f6 and I should think that any Cheshire will do for you.