Contains:  Extremely wide field
Milky Way Mosaic (Astrotracer), 



Milky Way Mosaic (Astrotracer)

Technical card

Imaging telescopes or lenses: SMC Pentax-M 28mm f/2.8

Imaging cameras: Pentax K-3 II

Dates:Aug. 11, 2018

Frames: 11x120" ISO800

Integration: 0.4 hours

Avg. Moon age: 0.10 days

Avg. Moon phase: 0.01%

Bortle Dark-Sky Scale: 4.00

Mean SQM: 20.90

Basic astrometry details job: 3263424

Resolution: 3076x4012

Data source: Traveller


This is a portrait-mode crop of a mosaic using eleven frames, each frame a single two-minute exposure. Given the cropping some of those frames are seen only partially here. The mosaic was constructed using Microsoft's Image Composite Editor (ICE).

The camera was mounted directly on a tripod, with the camera's Astrotracer feature providing sidereal tracking internally. The lens was stopped down to f/4.

Even though this was shot in the country, there was a considerable amount of light pollution on the horizon from a mid-size city roughly 25km SSE. This is the best I could do to eliminate it using a program called Sequator, which also did the stacking. Further improvement will require a more sophisticated gradient-reduction tool.

The dark band runnIng nearly horizontally through the middle of the image is curious. It does not correspond or align with any of the mosaic seams. It appears to be real. A dark cloud, perhaps?



Milky Way Mosaic (Astrotracer),