Hemisphere:  Southern  ·  Constellation: Monoceros (Mon)  ·  Contains:  Extremely wide field
Orion rising over Grand Canyon, composition check shot (Astrotracer), 



    
        

            AlenK
Orion rising over Grand Canyon, composition check shot (Astrotracer)
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Orion rising over Grand Canyon, composition check shot (Astrotracer)

Orion rising over Grand Canyon, composition check shot (Astrotracer), 



    
        

            AlenK
Orion rising over Grand Canyon, composition check shot (Astrotracer)
Powered byPixInsight

Orion rising over Grand Canyon, composition check shot (Astrotracer)

Technical card

Imaging telescopes or lenses: Pentax SMC-DA 18-135mm f/3.5-5.6 ED AL [IF] WR

Imaging cameras: Pentax K-3 II


Dates:Oct. 27, 2019

Frames: 1x30" ISO6400

Integration: 0.0 hours

Avg. Moon age: 28.78 days

Avg. Moon phase: 0.63%

Bortle Dark-Sky Scale: 2.00


Basic astrometry details

Astrometry.net job: 3296501

RA center: 6h 3' 51"

DEC center: -7° 28' 12"

Pixel scale: 42.494 arcsec/pixel

Orientation: 52.036 degrees

Field radius: 41.371 degrees


Resolution: 5887x3806

Data source: Traveller

Description

This is a single exposure taken with a stationary camera at Mather Point in Grand Canyon National Park (South Rim). Astrotracer was used for tracking, with the camera mounted directly to a tripod. The lens was at the 18mm end of the zoom range and stopped down to f/5 to reduce aberrations somewhat (although this lens never gets good in the corners at any f-stop). This exposure was just a composition check. For the sky, I took dozens of similar 30-second tracked exposures at a much lower ISO, to be stacked and composited with a longer untracked exposure I took of the foreground.

This image has not been processed other than minor curves adjustment. Although objectively unimpressive, it does give a good impression of what I experienced that night except for the sky seeming darker to my eyes and, of course, not seeing quite so many stars.

The overall reddish-brown color of the sky background and the green glow in certain areas are both the result of natural airglow, which was also not visible to my unaided eyes. Although it is natural, it essentially acts like light pollution in the sky stack and I will need to remove it using gradient reduction.

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Orion rising over Grand Canyon, composition check shot (Astrotracer), 



    
        

            AlenK