by Craig and Tammy Temple
A mere 7000 light-years distant, the famous Double Cluster in Perseus is nestled in one of the spiral arms of our own Milky Way. Easily visible to the unaided eye, these 2 clusters, NGC 869 and NGC 884 shine brightly at an apparent magnitude of 6.08. The two clusters are separated by only 100 light-years.
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: Self-modified Canon Digital Rebel XT
Filters: Astronomik CLS-CCD EOS Clip
Exposure: Best 26/31 x 300s @ ISO 400 (2hr. 10min.)
Acquisition: ImagesPlus 3.75 Camera Control
Processing: ImagesPlus 3.75 – Calibrated, registered, Sigma-clipped averaged, DDP
Post-processing: Adobe Photoshop CS4; Gradient XTerminator; Noise Ninja
Date(s): October 20, 2009
Temperature(s): 56ºF
SQM reading (begin - end): 18.78 – 19.17 mags./sq. arcsec