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So Confused..9.25SCT,7"mak or 7" mak-newt

Started by Settimio, 03/04/2003 08:00AM
Posted 03/04/2003 08:00AM Opening Post
Planetary only

I like the long focal lenght of the CAS design for
low power E.P. "el natural"(No Barlow)

The spot size & small CO of the MAK-Newt. Many say the best

The aperature of the 9.25 SCT for more detail.

Which to chose.........................

The first Step towards failure is trying. - Homer Simpson
Posted 03/04/2003 09:04AM #1
I've tried both the C9.25 and MN-76 (Mak-Newt).
I see more detail in the C9.25 on Jupiter,
in spite of the larger CO. C9.25 is also much more
friendly for binoviewing due to huge available
back-focus. Both have cool-down problems to some
degree; available fans help. Dewing is more of
an issue with the C9.25; hard to keep big thin
corrector plate warm. The MN-76 is a huge scope;
C9.25 is much more managable in size. Tough call.
Posted 03/04/2003 12:25PM #2
The length of the MN 76 will require a very beefy (and therefore expensive) Equitorial Mount. The 9,25 mcuh less so. The MN 76 is, however, a very flexible scope, and you could cut down the cost considerably by building a dobsonian type mount for it.

At that point, though, the PDHQ 8" f/7 dobsonian (with 1.5 inch central obstruction) from Discovery starts to look pretty cost effective at $800 for the scope and mount. The views in all three will almost always be limited far more by atmosphere than scope.

Of course, at some point you have to take matters into your own hands, and tell us to get off.