Atmospheric seeing is the driver for image resolution with a 1-m class
telescope. It's been my experience that the seeing at Stony Ridge varies,
on the average, from about 2-3 arc-seconds FWHM. There are probably
better nights of 1 arc-second seeing, but these seem to occur on nights
when the observatory is dark. ;>]
The first two images above were exposed about 25 minutes apart on a
very breezy night. As illustrated, poor seeing can be quite variable
and is especially damaging to faint objects. The third image in the
series represents good conditions, limiting magnitude is fainter, star
images are round, more of the starlight is concentrated in a smaller
number of pixels.
- - SCB 2002/02/02