2" Diagonal Question for C8 OTA

I just bought a used Celstar 8 unit with a 1.25" visual back and a 1.25" diagonal. I want to use my 2" eyepieces.

I have a nice William Optics 2" refractor diagonal I would like to use but I need to know what to buy to use that diagonal on my OTA. This is fork mounted and there seems to be plenty of room. Does anyone know where I can buy the right adapter? Also, I have read (can't remember where) that if the diagonal tube inserts too far into the OTA, you can cut off some of the light cone, reducing your field of view. Does anyone know if that would be a problem using this refractor 2" diagonal? Should I bite the bullet and just buy a 2" SCT diagonal? I hate to spend the money.

Any help would be much appreciated !!

Thanks,
Tom

Tom,

All you need is what is called a 2" Visual Back which replaces your present 1.25" visual back. I use the Astro Physics brand because it has the brass compression ring instead of just tightening screws. It is about $45. or $50. new. Do not worry about a 2" diagonal extending into your SCT. It will never get that close with a 2" visual back because the body is quite deep.

P.S. I see somebody else was posting pretty much the same answer while I was typing mine.

Tom,

I'm wondering the same thing with a C-9.25SGT. I really want to get that scope, but if it won't let me use 2" eyepieces, then its no good to me. Hence my confusion and consternation when my UK dealer told me it would not let me use a Televue 2" Everbrite Star Diagnol. The responses I am getting so far seem to indicate a 2" Visual back is the key to opening up the 2" eyepiece for use.

Malcolm