Re: What's the effect of imaging through jet stream?
I have seen about every geometric shape possible with out of focus stars during a FocusMax run with the 17", worse when the seeing is poor. According to my seeing monitor, I tend to run around 2" on average, with some periods of significantly better, 1.5" or less and sometimes 3" plus, on the same night. It can be reasonable right after sunset for about 30 minutes, and can be reasonable before dawn-sometimes. I have done what is possible around and in the observatory to minimize heat effects (I am in SE AZ), but I can't control the upper atmosphere.
Mike J. Shade
Mike J. Shade Photography:
In War: Resolution
In Defeat: Defiance
In Victory: Magnanimity
In Peace: Goodwill
Sir Winston Churchill
Already, in the gathering dusk, a few of the stars are turning on their lights.
Vega, the brightest one, is now dropping towards the west. Can it be half
a year since I watched her April rising in the east? Low in the southwest
Antares blinks a sad farwell to fall...
Leslie Peltier, Starlight Nights
International Dark Sky Association: www.darksky.org
email@example.com [mailto:firstname.lastname@example.org] On Behalf Of Glenn