I recently aquired a pretty decent LX200 10" OTA for a darned good price, and and now working on the bits and pieces necessary for a working instrument covering most of the basics, IE some eyeball astronomy and some photography. I opened her up and cleaned some lube looking gunk off the secondary (I think it was stored upside down somewhere), and picked up a set of Bob's knobs (heavenly!), and just ordered the Peterson's focus fixer kit. Years ago I'd picked up a set of rings at a yard sale for $10 (weird, just rings nothing else) and they looked like they'd fit a 10" SCT. And now, wonder of wonders, I ran across one I could afford, and even crazier, they did fit!
I'm feeling pretty lucky actually because other than the crud coming right off the secondary first go no issues, it's in very nice shape and has extremely minimal focus shift. The other night I was out having a go at Saturn and even with a 4x barlow in front of the imager, the frame filling planet barely shifted at all with focus direction. Pretty sweet. This is my first big SCT after years with refractors of various sizes and tons of reflectors, I definitely appreciate 10" of high FL horsepower in a compact package.
Which brings me to my issue, I'm well up on the imaging learning curve after a few years with all my other toys so I'm good there, but after being spoiled with a bunch of low F ratio reflectors and schmidt newts, now I'm wondering the best route to tame the F10 on this puppy.
Ideally I'd like to hit at least F5 to match the other 10" I've got in the lineup, but since this is my first SCT I have no experience with focal reducers. In doing some reading I'm finding out the ratio is variable with spacing, and also that there are a couple routes to go.
My primary imager has been a DSI with the 1.25 format and it's been a fun gizmo I've got some good shots with. I've found a number of 0.5x reducers at Agena and Astronomics, and it's my understanding you screw these right onto the front of the imager, with exact reduction dependent on the spacing.
And, in the recent past I picked up a Canon DSLR which I've used on my SN6 and also with it's native lens, with great results, so I'm kinda itching to let it run some more deep sky with the new SCT.
In that vein, there are the larger reducers which presumably fit into the visual back (?), or the front of a diagonal or extender...are they threaded, or plug in using an OD/ID fit like an extension tube? For these I'm refering to Meades and Celestron's official 'focal reducer' devices. I'm guessing you do NOT use the diagonal during photography, I got a 2" diag and visual back with the scope.
SO basically, i'd appreciate a short what's what and some ideas on what makes the most sense from the perspective of some folks who've used them.
thanks in advance...