M103 – Open Cluster in Cassiopeia

Telescope: GSO 8” f/12 Classical Cassegrain @ f/12, Orion Atlas EQ-G

Camera: Canon EOS Ra, Baader Mk III MPCC

Filter: GSO IR Blocking Filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 21x60sec, ISO 800, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/25sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, fair transparency

Lensed Sky Quality Meter: 18.4 mag/arc-sec^2

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard EOS, Deep Sky Stacker, Nebulosity, Photoshop

M103 is one of several open clusters in Cassiopeia. It is small, rather sparse, and was once thought to be an asterism rather than a true cluster, but it has since been shown to be a distant open cluster. Located just 1.5 degrees northeast of delta Cassiopeia it is easy to find and makes a nice target for small telescopes.

M103 is currently in the northwest during the early evening.