Reddit Gold: u/DanielJStein describes how to use a star tracker to take beautiful night sky photos

Reddit Gold highlights the most useful and educational content on Reddit as found on r/AutoBestOf.

Today’s post is from u/DanielJStein who describes how to use a star tracker to take beautiful night sky photos.

Both the foreground and stars were taken at the exact same time, same spot, same direction, and of course same focal length—50mm. I’d like to start out by stating that there is no way the human eye can see the night sky exactly like this. We as people persons cannot replicate the long exposure techniques and longer focal length lens used here. With that said, the Milky Way is still an incredible site to behold in person. You cannot really compare what is seen here on a tiny computer/phone screen to actually being surrounded by a sky full of stars in real life.

If you like this shot, feel free to check meowt on my Instagram @danieljstein where I post more nightscapes like this one!

As I said, I used a device called a star tracker to take this shot. This is a device which needs to be aligned with the associated celestial pole in order to accurately rotated the camera in conjunction with the Earth’s sidereal rate. In the case of this image, I aligned with Polaris as it is the brightest star closest to the north celestial pole, and Colorado is in the Northern Hemisphere. If I did not use the tracker, my exposure times would be significantly shorter, thus limiting how much detail I could capture.

This is a wider image I took last year in the Adirondacks which I tried to edit to represent how we see the night sky. Although it is not perfectly processed for how we see the night sky, I think it does a reasonable job of visually demonstrating what the bulk of the differences are. The Milky Way appears as a cluster of mystical clouds cluttered with stars spanning the sky. You cannot quite make out the specific details and nebulae, but you will see it and know exactly what you are looking at when you do.

Should you choose to venture to Colorado for any reason, please remember to be respectful of any rules, regulations, and leave no trace on site.

So get out and away from light pollution and see the Milky Way for yourself!

This image is an 3 image stack, consisting of 2 images stacked with a star tracker for the Milky Way exposure and 1 untracked image for the foreground. All shots were taken consecutively one after the next. No crazy compositing or swapping the sky for a Milky Way facing a completely different direction here.

I used my h-alpha modified Nikon Z6 and Sigma 50mm f/1.4 to take this shot. I took 2 tracked shots for the stars at f/2.8, ISO 800, and 2 minutes each. After the tracked shot sequence finished, I took another shot to capture the detail on the landscape at f/2, ISO 800, 4 minutes with the camera still on the tracker but not actually tracking. I did initial adjustments in LR on each image, then sent the foreground into PS and the star stack into StarryLandscapeStacker to perform the stacking algorithm. After this was done, I exported the image into Pixinsight. From there, I performed adjustments to reduce the noise, color collaborate, reduce larger stars, as well as bring out more data in the Milky Way Core. After this, I brought the output file into PS where I stitched it together with the foreground untracked shot manually. I used masking to correct for a small discrepancy between the layers while performing additional adjustments to my liking to yield this final result.

If you have any questions or feedback about this shot, astrophotography, or astronomy in the Colorado in general—feel free to ask below! My goal is to be 100% ethical and transparent with this process.

Here is an annotated image of all the nebulae and planets, astronomers correct me if I am wrong!


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