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Aperture and Seeing - An Extreme Example

Started by AlanFrench, 05/16/2008 03:05PM
Posted 05/16/2008 03:05PM Opening Post
One night, several years ago, we packed up my wife's 14.5" f/6 equatorial for a journey to the club's dark sky site. I packed my little 3.5" f/5 apochromat too.

We arrived before dark, and even the 14.5" doesn't take long to set up, so it was not completely dark when I was done. Since it was bit too early for deep sky observing, I pointed both scopes at Jupiter, which was well placed and fairly high in the sky. The seeing was absolutely horrid - about as bad as I can ever recall. Both the 3.5" and the 14.5" only revealed the NEB and SEB, both devoid of detail.

As I was looking through the 14.5", exclaiming to Sue how awful the seeing was, suddenly, for a brief moment, there was Jupiter in stunning, Voyager like detail. It was amazing. This kept happening - fairly long periods with a most pathetic Jupiter, interspersed with fleeting glimpses of tremendous detail. These brief moments were not nearly as impressive in the smaller scope, which, of course, was not surprise.

Clear skies, Alan