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Magnification demo

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#1 Bonco

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Posted 09 March 2013 - 04:17 PM

Last night had transparent skies but not so steady. With my 4 inch f/15, no luck with E or F in the Trapezium and no joy on the "Pup". The 4th star of Sigma Orionis was harder than I expecded confirming unsteady air. So I decided to play with magnification and see the results. Best view of the dim star was with 9mm/166X. Using my favorite 4.8mm Nagler at 312X the star was 100% invisable. Good demonstration that correct magnification for the conditions is paramount for dim doubles.
Bill

#2 azure1961p

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Posted 10 March 2013 - 07:58 AM

It's dispiriting just how detrimental poor seeing can be to doubles and conversely just how flattering in good conditions. There have been a few nights this past winter where either a 26 or 20mm ocular were about max for stellar clarity before bloating or disappearance became evident.

Pete

#3 Ed D

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Posted 12 March 2013 - 07:01 AM

I have a few eyepieces in my case that I sometimes wonder why I have them. Then, a night happens just as you describe and I realize their value and why they're keepers.

Ed D

#4 azure1961p

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Posted 12 March 2013 - 10:01 PM

There is a beauty to low power doubles on those nights. The success I've found is having a backup list for those poor seeing nights that can turn it into something's profitable.

Pete






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