Determining Seeing Conditions

[nightster]

Other than making a visual observation, is there a way to measure Seeing Condition with my imaging rig?  I had what I believe to be an exceptionally good seeing weekend with low humidity for this area, cooler temps, etc.... I would like to be able to benchmark those condition against future nights so I know how that affects my images.  Can I use the data collected to measure the seeing?

[Pompey Monkey]

You could try to keep a log of your FWHM for each session and see if you get a correlation with the subjective seeing. That might be a start.

[Earl]

I do belive a unihedron does this (need to get mine up and running), currently i use ccd inspector on my fits and use that to chose if i select any subs to take out of the processing.

http://www.firstlightoptics.com/unihedron-sky-quality-meters/unihedron-sqm-l-sky-quality-meter.html

[Pompey Monkey]

Other than making a visual observation, is there a way to measure Seeing Condition with my imaging rig?  I had what I believe to be an exceptionally good seeing weekend with low humidity for this area, cooler temps, etc.... I would like to be able to benchmark those condition against future nights so I know how that affects my images.  Can I use the data collected to measure the seeing?

Are you talking about "seeing" or "transparency"?

Transparency is essentially a measure of how faint you can go - think faint fuzzies - it affects not only the direct light path from the stars, but also has a bearing on how much back-scattered light from your local environment you get (i.e. light pollution).

Seeing is a measure of how still the atmosphere is - think planets and double stars shimmering around at high power.

You can have excellent seeing with poor transparency (e.g. muggy summer nights), or poor seeing with excellent transparency (e.g. crisp winter nights). To get both together is quite rare here in the UK, but I don't know much about Charlotte, NC, other than that it is fairly inland and may well benefit from more continental weather which is often better for astronomy.

The FWHM of your stars will tell you how good the seeing is, while the sky meter that Earl mentioned will tell you how good the transparency is.

Here is a good guide to one particular seeing scale: http://www.damianpeach.com/pickering.htm