Abell 21 or The Medusa Nebula is a planetary nebula in the constellation of Gemini.

Canon EOS 6D (Baader filter modified) @ ISO 6400

Stack of the best 100x45 sec subs with calibration frames added.

Celestron C11 at f7 Cropped.

Tracked on a Skywatcher AZ-EQ6 mount with no guiding.

Polar aligned : Polar Scope.

Acquisition : Intervalometer.

Imaged from suburbia through a IDAS Light pollution LPS-P2 2.00".

Processed in APP and finished off in LR.

Done