Swan eyepiece set for a C9.25

[Astronut]

I'm intending to get a C9.25 XLT OTA + an EQ6 goto mount sometime this year when finances allow.

I've only just started looking into suitable eyepieces and this set has caught my attention.

https://www.william-optics.com/wo_shop/catalog/product_info.php?products_id=102

The 2" dielectric diagonal included has some rave reviews so it may be a good deal but I don't know too much about Swan eyepieces. From what I've read they're not too good on fast scopes (loss of sharpness at FOV edges) but for an F10 SCT they may be OK.

Would the 2" diagonal fit the C9.25 or would it need some modification or additional adaptor?

Also, probably a dumb question, but what is the advantage of 2" eyepieces over 1.25"? I remember reading somewhere that vignetting may be a problem with 2" eyepieces on some setups but would this apply to a C9.25?

6 eyepieces + a superb diagonal seems like a good deal at the current exchange rate. I can't find any UK dealers though - anyone know of any?

Any other thoughts or guidance on eyepiece selection?

I'd like to get a focal reducer too, maybe a Celestron f6.3 which may not be a good combo with these eyepieces given the FOV edge focus softening for fast focal ratios I've been reading about.

[iancandler]

I havent used the swan eyepieces but I do use a 2" dialectric diagonal with my sct even though its only a lowly C5..

All you need is a 2" visual back, which is just an adaptor that converts from sct thread to 2" push fit.. you can pick them up for under £20 most places, but make sure you get with with a compression ring.

I find 2" eyepieces give a much better view, especially at longer focal lengths.. ie 26mm - 40 mm.

In fact the best view I ever had of M42 was with a 26mm GSO plossl that came with my old revelation dob.

Keep an eye out on ebay for an american company called smart astronomy.. they do a really good 2" diagonal for silly money, and postage is good from them too..

I would recommend the focal reducer, it makes a difference but mainly if you want to use it for astrophotography.. I went for the antares one and havent been dissapointed with it at all.