Sky! Sky!
hawcheng wrote on Apr 22, 2010
If there is no moonlight, how much variation in the sky brightness for a given field can I expect? I have 40 exposures of the same field taken across a year, and after accounting for exposure time differences, I'm still finding the sky level to vary by as much as 50%.
I know this isn't a question specific to IRAF, but since this is such a community of astronomy experts, I thought I'd throw it out there. :)
I know this isn't a question specific to IRAF, but since this is such a community of astronomy experts, I thought I'd throw it out there. :)
H.J. van Heerden wrote on Apr 22, 2010
Sky brightness may also change due to weather conditions and/or light pollution.
High cirrus clouds that might be invisible to the eye can still reflect significant enough amounts of light to vary the sky background. If possible - check weather data for the specific nights in question - barometric pressure as well as dew point temperature - that will tell you the amount of moisture in the atmosphere.
Regards
Pat
High cirrus clouds that might be invisible to the eye can still reflect significant enough amounts of light to vary the sky background. If possible - check weather data for the specific nights in question - barometric pressure as well as dew point temperature - that will tell you the amount of moisture in the atmosphere.
Regards
Pat
Last post on Apr 22, 2010