![]() ![]() We’re off for the holidays, so I thought I’d take the time to talk about something fun: Astrophotography.SkySafari 6 Plus APK: Your Ultimate Books & Reference App for Android When I was around ten or eleven years old, I got an inexpensive Newtonian refractor for Christmas. It was good for visual use, and was super unstable on a pressed metal tripod, and was difficult to focus. But that didn’t stop me from standing out in the parking lot of our apartment complex, in the cold, to look at the moon and stars. The telescope was not very high power, so I couldn’t see much detail on the moon, but that didn’t stop me from being amazed at what I could see. This added to all the other space flight and astronomy stuff I had in my room, like the huge poster of all the rockets to-date, the models of the fairly-new Space Shuttle, my science fiction books, and more.ĭisclosure: this post contains a number of third-party products. I paid full price myself for each of them. None were gifted or subsidized by Microsoft or any third-party. I did get a small discount on the first-party Surface Pro 8 as an employee of Microsoft. I’ve always like astronomy, and wished it was the science I could have taken in college (rather than Physics) for my Computer Science degree. I just find it both beautiful and inspiring. I’m not interested in just seeing things, though. I want to share them with others, and then save them for future reference. So, this summer, I started a journey into astrophotography. I’m still quite new to this, but have learned a lot, and also run across some very cool technology I wanted to share with you. First I cover some of the basics in astrophotography so you know which problems we’re solving, second I cover some hardware and my own setup, and then third, I get into the software used, including software built in. Key challenges in deep-sky astrophotographyįirst, a little background in the types of processes involved in astrophotography. Keep in mind that, like most things, these were handled manually in the past, or used analog processes. ![]() It’s important to remember that the earth rotates, and at an angle. This is approximately centered around Polaris in the northern hemisphere. ![]() If you want to avoid streaked stars, and keep the same framing of the object you’re imaging, you want to use some variation on a German Equatorial Mount. (You can also use an automatic field rotator and an altitude/azimuth mount like many large observatories, but we’ll stick with the GEM approach here). To use this kind of mount, you need to point the mount to (in the northern hemisphere) Polaris as closely as possibly. Once the mount itself is pointed to Polaris, it will be able to track deep sky objects correctly, keeping them in frame. This is super important for long exposures, which are often used for galaxy and nebula photos. In my own setup, each frame is typically 3-5 minutes long. Polar alignment is a manual process, involving tweaking adjustment screws on the mount until Polaris is within some error margin of center. You can do this completely manually with a polar scope, or you can use software which helps you out by telling you how well you’re doing. If you want to learn more about Polar Alignment, there’s a great article here. Polar alignment is just one aspect of proper tracking of an object. Most mounts are able to use time-based algorithms to track an object in the sky. I use this for tracking the moon, but it also works well for planets. But because alignment and tracking always have a margin of error (including the fact that Polaris isn’t at 100% center of rotation), and due to things like wind, vibration, any instability in the mount due to mechanical or balance issues, etc. you typically use an autoguider to help with keeping the object in the exact center of the screen. There are multiple ways to do this, but a common approach is to use a smaller guide telescope attached to the main scope, a black & white camera, and software such as PHD2 to latch on to a star and send commands to the mount to make micro adjustments.Īnother important process is Plate Solving. Plate Solving is when you take an image, and then identify through the positions of the stars, the location and orientation of what the scope is imaging. SKYSAFARI PLUS WINDOWS SOFTWAREĪs you can imagine, this is an ideal situation for software to step in and handle the plate solve for you. There are many plate solvers out there, including online ones. Each one has different strengths and weaknesses. Some use more compute power, some are more accurate in different situations, etc. Plate solving is also important for coming back to teh same target over multiple days, months, or years, which is quite common for faint deep-sky objects. ![]()
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