
This is an image from the SeeStar S50 captured around October 27 2024 in alt-az mode with mosaic imaging. Mosaic imaging means that the image is larger that the normal capture frame (in this case, about twice as big) so the system captures a number of images around the central frame and then merges the images together for the final picture. Alt-az means the telescope is oriented with axes pointed to the zenith and parallel to the horizon.
This is a fairly noisy image and took quite a while to capture, but you will note that there are no obvious rotational artefacts. The S50 first captures a central image, then spirals in a clockwise direction to fill in the edges, with the process repeating until capture is stopped. The central part of the image is therefore captured multiple times with the edges of the frame having a lesser number of captures. Image captures were eventually blocked by the house, so the time was somewhere around 22 minutes for the entire process – not a particularly long time.
I’m trying to set the same region up for an equatorial mode capture, but the Horsehead Nebula is a little south of the equator, and one limitation of the SeeStar software used in equatorial mode is that objects below the celestial equator are considered as being below the horizon and can’t be captured. There may be workarounds…
Even though this is a noisy capture, you can see that the dark Horsehead is superimposed over a brighter red glow caused by hydrogen gas ‘excited’ by the light of nearby stars. On one side the number of stars is much higher than on the other: the darker area is covered interstellar dust which blocks the light from stars in the background. There’s a lot of dust in this area, and longer exposures will reveal more details – the dust reflects a little light from nearby stars, but not enough to be seen in this short capture.
For a comparison, the image below was captured in December 2023 with the default Seestar framing.
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[Note that clicking on the images should increase the magnification so you can pixel-peep]


