[RickS (Rick)]

Originally Posted by Andy01

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Now we're also wondering if the Stellarvue SFFR-70APO flattener/reducer is right to use with the RC8?
It's designed to be used with the SV70T which is only 420 mm FL, the RC8 is 1625mm FL. - Hmmm...

Good to see you've made progress, Andy.

What you want is a flattener/reducer that matches the field curvature of the scope and that depends on the scope design and f/ratio. I wouldn't worry about the FL in isolation.

In the absence of an optic designed specifically for the RC8 it's a bit of a crap shoot I was pretty happy with the AP 27TVPH on a RC10 but anything bigger than a KAF-8300 showed its limitations!

Cheers,
Rick.