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Plate question - mounting a reflector

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#1 mnaf

mnaf

    Viking 1

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Posted 21 March 2009 - 05:19 PM

About 9 months ago I picked up a used "17.25 in." Losmandy plate - DAP6 - to mount a 38" Orion 8" reflector on a new mount (to be delivered soon).
Turns out it's really a 24" plate!
Didn't realize it until I received a real 17.25" plate today to piggy back on the other. Embarrassing I didn't measure the first one - I just stored it. :foreheadslap:

I could pick up another 17.25" plate and sell the 24" but would the 24" be more stable with a 38" newt.? Longer seems that it'd be more stable. The saddle on the new mount will be 16" long. And I've got 2 sets of 8" rings available.

The 2 options I see are:
Use the 24" on one set of rings and use the other ring set between the 24's to mount the 17.25" plate on top.
Or,
Get another 17.25' and sell the 24" - use only one ring set.

Stability is most important since imaging is the primary use. Someone must have an idea on this.

Any advice would be really appreciated.

#2 Tom and Beth

Tom and Beth

    Soyuz

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Posted 22 March 2009 - 12:44 PM

If I were you, I'd try to trade the 17 incher for the 24.

1) your saddle is 16 inches. The longer plate gives you more flexibility for balance as you swap cameras and such

2) your assumption that the longer plate would be stiffer is correct, although with a short tube...it probably doesn't make much difference.

3) there's a small penalty in weight.

FWIW, I used he 24 incher on a 6 foot long Newt. I'm 100% visual, BTW.

This is an old pic, before I moved up to an AP1200.

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