September 23, 2024

M46 – Open Cluster in Puppis

M46 – Open Cluster in Puppis

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: 24x120sec, 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, poor transparency

Lensed Sky Quality Meter: 18.1 mag/arc-sec^2

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

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

M46 is one of several relatively bright open clusters that grace the evening sky in winter and early spring. This cluster also sports a beautiful little planetary nebula (NGC 2438) in the foreground. This little nebula looks quite stunning in a modest size telescope with the rich open cluster in the background. I first found M46 with my homemade 10” f/6.7 Newtonian during a Messier Marathon in 1978. I’ll never forget seeing the little planetary nebula in the foreground, it was so neat!

This is one of a series of images taken to evaluate using the GSO CC8 with a Baader Mk III MPCC and a full-frame DSLR for high resolution deepsky imaging. The initial results are quite encouraging.

M46 is currently well placed in the southeast at sunset.