Astromania 1.25Inch Metal Collimating Cheshire Eyepiece Without Laser for Newtonian Reflector Telescope - Short Version

Good quality all metal construction. Works exactly as it should!

Good price, did its job.

Seems to work good. I use i then my laser. I would have bought this first if I had known.

This Cheshire eyepiece enables a precise adjustment of the secondary mirror, once you get it spaced correctly. A four inch extension was right for my ten inch Newt.My mirror was significantly off, requiring adjustment. I expect an improvement in my pictures. It's surprising to find such a well made item these days; the eyepiece is beautifully manufactured of heavy duty metal with an excellent finish. For the money it's an unbeatable value, if you have Newtonian telescope you need this.

Laser collimators are really convenient until you realize the device didn't hold calibration from shipping. Easier to ditch the convenience and get a Cheshire that's nearly as simple to use with the added peace of mind not having to worry if a laser is out of alignment. The only downside is being restricted to collimating your telescope during the day. You need plenty of light to use this bad boy.

I use this with my 10" dob. It has a small field, so if you are very far out of collimation start by just eyeballing down the eyepiece tube and line things up. There are plenty of online resources to use these. Be aware that what it does is center the eyepiece to the center of the mirror. It isn't necessarily the case that the center of the parabolic curve is centered mechanically. Check your star shapes to make sure there isn't any coma after the collimating eyepiece is used.It is well made and all metal.

Works really well, but you have to know what to expect and what to do. Read up or check online videos on how to use a collimating cheshire. The pinhole you look through on this one is very small, and the collimator is very short. The crosshairs are clear, and it works for collimating my 114mm reflector.Edited: May 4, 2018I used this in the past few days to collimate my AR127 and ST80 refractors, so it works for refractors as well. You can unscrew and remove the crosshairs frame, a much appreciated feature of this cheshire. It looks like the crosshairs can even be screwed into any other 1.25" eyepiece, much like a filter, and used in centering stars and planets.For refractors, you should use a laser collimator to align the focuser tube to the primary lens first and foremost. If you need instructions on how to collimate a refractor, there are a lot of good resources online, especially in the backyard/amateur astronomy forums.

I was hoping to be able to fine tune my scopes using this tool. It was no help. I can visually achieve better collimation before switching to a star. Initially when I used it I was thinking “man I was further off than I thought”, but nope I was moving out of collimation with this tool.

Excelente muchas gracias

Not bad but the barrel is so short that it’s hard to make out the crosshairs, making it unusable. Worth investing in a longer one

Well I have now tried this and although i managed to Collimate the Telescope I then tried a laser version and found that I hadn't quite got things centered worked Ok in general

I am extremely disapointed with this Collimator! It arrived after a shipping delay which I can live with, but the product quality is absolutely terrible. I added some pictures to show what I am talking about. The inside of the optical tube is not anodized on one side and the finishing is terrible. Also for a brand new Collimator the bottom end cap looks like it has been used and aged. It is not worth sending the unit back due to the shipping costs - but for optical equipment this is just terrible.I have purchased several telescope eyepieces from Amazon, but I have never seen anything like this before!