Celestial hemisphere:  Southern  ·  Constellation: Ophiuchus (Oph)  ·  Contains:  Extremely wide field
Milky Way Sagittarius-Scorpio, Rod Van Meter
Milky Way Sagittarius-Scorpio
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Milky Way Sagittarius-Scorpio

Milky Way Sagittarius-Scorpio, Rod Van Meter
Milky Way Sagittarius-Scorpio
Powered byPixInsight

Milky Way Sagittarius-Scorpio

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Description

The constellation Sagittarius is center left, Scorpio center lower right. The brightest, red star is Antares. Just to the lower right of it is M4, a globular cluster I'd love to take a good photo of. This was shot at 24mm focal length, cropped to about 50%. This is 45 minutes of total camera time, 90 exposures of 30 seconds each, stacked, along with about 37 "dark" frames (shot with the lens cap on) and 82 "flat" frames, used to correct for lens vignetting.⁠ One friend wanted to know if this is what it would really look like. If you could stare at the same spot for about 45 minutes, yes, this is roughly what it would look like. I did no color correction. The camera was set to 5500K (sunlight), but since the processing was all done on raw frames that has ?no? impact. (I think the processing software I used might use info from the camera's internal settings to guide its settings when importing the images? I'm not sure.) In-camera noise suppression is turned off, since that's the software's responsibility. Camera was mounted on a SkyMemo equatorial mount. My alignment to the North Pole was probably about 1/4 of a degree, maybe a bit better. At 24mm I could have shot longer exposures, and processing would have been easier and the color a little better, less noisy. (Though 90 frames does a lot for that!) I should have spent some time "grading" the individual frames before combining them all. I'm sure several weren't very good, either mount vibration or brief clouds passing through. Airplanes (of which there were many, despite the evening hour and low airline traffic) are taken out by the combination algorithm. Unfortunately, it also took out the meteors, which it would be nice to add back in. This was shot at the beach, with rocks in the foreground, cropped out in this image. I'd like to take another shot (ha!) at processing and compositing in the beach.

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Milky Way Sagittarius-Scorpio, Rod Van Meter