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An Early Season M42

astrophotography dslr tripod


Alen Koebel

An Early Season M42

Orion was on its way toward the meridian early one cold morning in early October when I got a few minutes on it with a vintage 300mm telephoto lens. No flats, bias or dark frames but I dithered and used kappa-sigma clipping during stacking. Camera on tripod only with tracking using Astrotracer (built in to camera). This image has been cropped to about 25% of the original APS-C frame (by area). Strong longitudinal chromatic aberration (red bloat) remains in the image, which is a result of the vintage nature of the lens. That can be reduced significantly with more comprehensive post-processing.

_Imager: Pentax K-3II DSLR (APS-C). _Lens: SMC Takumar 300mm f/4 @ f/5.6 _Exposure: 12 minutes (36 x 20s @ ISO 1600). _Tracking: Astrotracer (built in) _Date: October 5, 2019. _Location: Near Conestogo Lake, Ontario, Canada. _Sky Conditions: Bortle 4 (SQM ~20.9), better-than-average transparency.

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