Collimination

[RonVen]

I have a Astromaster 114eq. It is a bird-Jones Newtonian with a corrector lens in the focuser. Right now all is right, but down the line, the scope will need to be collimated. The Celestron manual recommends alignment of the secondary mirror with a Cheshire collumation eyepiece (without removing the corrective lens). For the primary mirror they recommend viewing "concentric silhouettes" and a final night time star collimation.

I have seen various collumation methods for this scope on the net from a full blown: take the focuser out and remove the corrector lens, mark the center spot on the primary mirror and other assorted items were removed to do a newtonian colimation. Is there a middle way where the least amount of items are removed and the collimation will be decent? Thanks for your help.

Ron

[Daniel-K]

A simple Cheshire will do just fine for visual. There cheap and user friendly shout take about 5 mins to do

[bod00]

I have the same scope and its a nightmare to collimate! - i used a centre cap and laser collimator but quickly found out you need to remove the corrective lens. I have thought about taking the primary out and centre spotting but to be honest i would just use the cheshire collimator as this will be the best tool as you wont have to take anything apart!

I managed to get mine 98% collimated with just the cap so i am sure you will get close enough with a cheshire (this will also be a good tool with any other scope should you upgrade)

With the mirror been relatively small i would think you would only need to collimate a couple of time a year unless you are been pretty rough with it!

I had such a bad time with my 114 that i bought another scope and the difference is unbelievable, not only the views but collimation takes about 2 minutes with the laser!

First light optics sell the cheshire and loads of others online too, but if you are happy with the views your getting then its probably ok anyway!

Good Luck!

[jimmyjamjoejoe]

Not sure how you'd do the primary with no center spot using a cheshire. If you dont intend to spot it, you may as well just use a cap to sort the secondary and star test for the primary.

[RonVen]

Thanks for all your posts. My plan (when I need collimation) is to remove the primary mirror to mark the center and leave the corrector lens in. I will purchase a cheshire & hope for the best. I'll post my results, when I finally do it. Thanks again.

Ron

[umadog]

Yes, a Cheshire absolutely requires a centre spot. Also, unless there's something I'm missing, the manual is wrong--not everything should be concentric. It should look like this: http://www.cloudynig...r_explained.JPG

[NSS_Ian]

I had to collumate one of these for a customer today &  I am reminded of why I do not sell these types of scopes.

Difficult and time consuming to Collimate, especially using a laser and have to remove the corrector !

It needed to be collumated as it was unusable !

My advise, stick to a standard Newtonian !