andyc
07-07-2014, 07:33 PM
With an extraordinary run of clear evenings in the Shire of southern Sydney (well, it is if you hail from Scotland :lol:), I've been able to image Pluto using my EOS 60D and 55-250mm lens, mounted on an iOptron Skytracker for six consecutive nights. Each frame of the animation is a stack of 5 x 2-minute exposures at 250mm, f/7.1 and ISO 2000, processed in DeepSkyStacker and Photoshop. The Pluto frames were taken from my moderately light-polluted backyard, the Milky Way snap was from west of the Blue Mountains.
Over these 120 hours, Pluto moves about 7.5 arcmin, or 1/4 the apparent diameter of the Moon. The very faintest stars detectable are magnitude 16.0 (magnitudes from Starry Night Pro and WikiSky), and Pluto is mag 14.1. It's handily located near the Teaspoon asterism, the open cluster Collinder 394 fills much of the left (east) part of the frame, and BB Sagittarii is the right-most of the bright pair of stars. Unfortunately saturation of the detector has likely robbed me of the variation in BB Sag, apparently a Cepheid with a period of a week and a variation of about 0.7 mag.
A larger version of the animation is available here (http://www.pbase.com/andycasely/image/156446937/original) (it's a bit grainier in the compressed animated gif below)
A larger version of the multi-frame zoom image is here (http://www.pbase.com/andycasely/image/156465758/large).
I'll continue the sequence if it's clear, but moonlight is becoming a problem, necessitating me to stay up later and later...
Over these 120 hours, Pluto moves about 7.5 arcmin, or 1/4 the apparent diameter of the Moon. The very faintest stars detectable are magnitude 16.0 (magnitudes from Starry Night Pro and WikiSky), and Pluto is mag 14.1. It's handily located near the Teaspoon asterism, the open cluster Collinder 394 fills much of the left (east) part of the frame, and BB Sagittarii is the right-most of the bright pair of stars. Unfortunately saturation of the detector has likely robbed me of the variation in BB Sag, apparently a Cepheid with a period of a week and a variation of about 0.7 mag.
A larger version of the animation is available here (http://www.pbase.com/andycasely/image/156446937/original) (it's a bit grainier in the compressed animated gif below)
A larger version of the multi-frame zoom image is here (http://www.pbase.com/andycasely/image/156465758/large).
I'll continue the sequence if it's clear, but moonlight is becoming a problem, necessitating me to stay up later and later...