Revelation 2" diagonal on 6SE

[trevscope]

Does anybody have any experience of a Revelation 2" diagonal fitted to a Celestron 6SE? I made enquiries about the size, and the dealer says that it won't fit due to hitting the focuser. I'm sure I've seen pictures of one fitted to a 6SE, but can't find it again (typical!). I know that a WO one fits, is that because it is mounted further from the tube and so clears the focuser by length?

Thanks,

Trevor

[Rob_UK_SE]

Hi Trevor,

You can fit a 2" diagonal, but the baffle size will make any eyepiece with a field stop beyond 27mm less suitable. You will loose light around the outer edge of the eyepiece.

A 40mm plossl with a 1.25" barrel is about your lowest possible magnification without the vignetting (light loss).

My recommendation would be to stick with the stock one (I have still to be convinced there is much of a difference with different with diagonals) and invest in a good wide angle - such as Baader's Hyperion 24mm, or alternatively a low power plossl such as the 32mm or 40mm.

Hope this makes sense.

Rob

[Dunkster]

I recently invested in one of those (the SCT type) for my 6SE... it does fit, but you are slightly restricted in how much you can rotate the diagonal without hitting the focuser. That's not a problem for me... I setup the OTA so that the focuser/diagonal are arranged in a given way, and I tend not to change that through a session.

As Rob says, the baffle size restricts its use somewhat so my impulse buy went against logic, but I bought with intentions of upgrading at some point

[trevscope]

Thanks for the prompt replies. There are a number of reasons that I was looking at a 2", first because the eyepieces that I mainly use are a Baader Hyperion 24mm, and Baader 8-24 zoom; these are a real pain to tighten up with the thumbscrews of the stock diagonal, so I was looking at a 1.25" diagonal with a compression fitting instead, when I saw the Revelation diagonal for £82 at scopes n skies, not much more than the 1.25" one. Also I like the screw in type for mechanical safety (I don't really trust the screws on the visual back, and those big eyepieces are pretty heavy, especialy with a camera attached!). Lastly I was thinking about if I ever upgraded the tube to 8", where a 2" diag would come in handy.

As for FOV, I think that I'm pretty near the max with the Hyperion 24 (about 1.1 degrees), I'm not sure whether or not I could get away with the 2" Hyperion 31 without too much vignetting, but I'm under no illusions about the max FOV (I read somewhere that you could get 1.3 degrees out of it, but I'm not sure!)

Thanks,

Trevor

[Dunkster]

Your conclusion Trevor is very similar to mine. I've only had one session with it so far, but no probs as yet besides the understanding that it doesn't freely rotate through any angle with the focuser there. It's pretty meaty too, at least compared with the stock Celestron 1.25. It does hold the 1.25 EP nice and steadily.

I saw a thread on CN about the FOV of the 6SE so became curious about the 2" EP, but not brave enough (yet) to get something too outrageous, but that might soon change

[E621Keith]

If you are buying a 2" push fit diagonal, you can always get a longer visual back. That should solve the problem of it hitting the focuser knob.

Using 2" accessories on a 6SE will not give any optical advantage over 1.25", but it will the increase strength of the mechanical connection. Sometimes, when I barlow my zoom eyepiece, the torque is sufficient to unscrew a the diagonal's nose piece.