"Alan W. Craft" wrote in message
...

I'm considering a Parks classic Newtonian,
and to mount on a Vixen GP-DX equatorial
mount. While their 8" f3.5 seems to be just
a wee bit too fast, and their 8" f6 a tad too
slow for DSO's and the like(not to mention
the tube length), I've looked into the
possibility of an 8" f5 custom-made by
Parks and sold via Scope City...

Check out the recent issue of Sky and Telescope about observing DSOs
and the merits of high or low magnification. "Slow" scopes are fine for
many such objects. The conventional wisdom dictating fast scopes simply
doesn't hold up in practice, once the other variable of vision and observing
are factored in.

Cheers,
Larry G.