Since I moved up to the 800mm focal length scope M42 doesn’t fit neatly into the frame on a APS-C DSLR and since I wanted to image it this season I decided a four frame mosaic was the way to go. This was taken over three nights, got around 3 hours per frame. I used Pixinsight HDR tools to merge 5sec and 30sec core exposures with the overall image.
Image Location and Date: Orange County Astronomers dark site in Anza, CA, Dec 15th, Jan 5th and 12th
Object: M42 Great Orion Nebula
Mount: Orion Atlas EQ-G
Imaging scope: Orion 8″ f3.9 Astrograph
Imaging FL: 800mm
Imaging focal ratio: f3.9
Imaging camera: Canon 1100D (Rebel T3) Modded
Lights: 134x300sec @ ISO 1600 RGB Total, average around 33 per frame.
Calibration: Darks, flats, Bias
Guide scope: Tair-3c with Orion StarShoot Auto Guider
Other details: guiding with PHD, captured with APT, processed in PixInsight + PS