by Craig and Tammy Temple
M48, a magnitude 5.50 open cluster in the constellation Hydra, is a bit of a mystery. It was discovered in 1771 by Charles Messier, however there is no open cluster present at the coordinates he specified. Caroline Herschel is credited for discovering NGC2548 (M48), which is the closest object to Messiers coordinates.
Telescope: Astro Tech AT8IN 8” f/4 Newtonian
Accessories: Baader MPCC
Mount: Orion Atlas EQ-G controlled by EQMOD
Guiding: Orion StarShoot AutoGuider on William Optics ZS66
Camera: Canon Digital Rebel T1i, Hap Griffin Baader modified
Filters: Astronomik CLS-CCD EOS Clip
Exposure: 49 x 120s @ ISO 400 (1hr. 38min.)
Acquisition: ImagesPlus 3.80b Camera Control
Processing: ImagesPlus 3.80a – Calibrated, registered, Min-Max excluded average, DDP
Post-processing: Adobe Photoshop CS4; Gradient XTerminator; Noise Ninja,
Date(s): February 10, 2010
Temperature(s): 27ºF
SQM reading (begin - end): 18.96 - 19.13