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Upgrading visual back and diagonal on CPC 1100

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I am a little disappointed in the quality of the 1.25" diagonal that came as standard with my new CPC 1100. It is a bit cluncky getting EP's in and out and the locking screws seem to have too much slack in their threads so getting a nice tight fit is difficult.

I am also considering buying a new EP that will give me a wider FOV than my 40mm Omni Plossl but everything I have looked at that would be a significantly wider field is in 2" format, so I am thinking of replacing the current visual back and diagonal with a 2" and using a reducer so that I have to option of using 2" or 1.25" EPs.

Can someone please recommend some good options for doing this? Is it possible to buy the visual back, diagonal and 2"-1.25" reducer as a set or do these things all come separately?


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I bought the Celestron XLT 2" diagonal and it is a great bit of kit.  Will screw straight onto the SCT thread on the rear of the OTA, and the 2 - 11/2" is adapter included (it is also threaded to accept 2" filters) and all EPs are held via compression rings so a great fit.

The Baader clicklock system also gets great reviews

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A vote from me for the Baader clicklock system.  I bought a used refractor and it had a clicklock 2" fit in place of the standard fitting.  Blimey, I can't see how it could be bettered, a vice-like grip is no exaggeration.  I'm going to buy a clicklock fitting back for my SC - hoping I can save a little money on one at Astrofest.

I have to say I wouldn't use any diagonal with an integral SC screw fitting straight onto the OTA of a SC.  I've used them many times over the years and have never found them to be reliable.  I either end up doing it too tight so it's difficult to undo to turn the diagonal, or too loose and it rotates when I don't want it to.  Of course this may be my ineptitude, I'm sure folks will use them and be very happy.  I guess, as always, it a case of try before you buy.

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I'll be looking to upgrade the stock items on a recent CPC925 purchase, having researched, it looks like it's going to be:

Baader 2" SCT clicklock back

Baader steeltrack

Baader 2" clicklock diagonal

Some lovely 2" eyepieces when funds allow :-)

And probably some sort of counterweight system!


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I also have the Baader 2" SCT clicklock back, Baader 2" clicklock diagonal and an Altair 2" to 1.25" self centring eyepiece adapter. A vast improverment on the original Celestron setup.

Other members are better qualified than me to recommend EPs but for the price I find the 38mm Ascension SWA from Opticstar gives a good wide view in this scope albeit with some astigmatism at the outer edge - I originally purchased it as a finder EP but it is now probably my most used EP, certainly on the larger DSOs.

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