Hey followers, Marcus here! I’ve mostly been in the background, using my telescope and letting my mom guide with posting and writing. Now that I’ve acquired some experience and understanding, it’s time for me to take the lead and explain about my progress so far.
Over the past 2 months, I've learned much about the primary concepts of astrophotography - aligning, tracking, and imaging. The learning curve has been VERY steep - steeper than I anticipated, and patience has been key. On occasion, I've had to recruit my father to help with some technical issues I just could not figure out.
My mom has posted a few pictures of my setup, sparking curiosity as I know that it looks like a lot more than just a simple "telescope". So for the geeks out there, here’s my entire setup:
But here’s the important take-away from the fancy terminology and pictures: my camera is attached to the telescope, so that the telescope acts like a giant camera lens. The camera and telescope are attached to the mount and tripod, and the setup is controlled by my laptop.
SO, what have I been able to accomplish? This:
Not crystal clear (yet), but that's Mars on the left and Saturn on the right. Nowhere near perfect by any means, but these first results have made every second of confusion and research worth it. And, I'm determined that future results will only get better!
For those of who are only interested in the aesthetics of astrophotography (like my mom), I’ll catch you later in the next blog post!
(For those of you who are more inclined to understand the technicalities, theories, and challenges associated with astrophotography, read on!)
The hobby of astrophotography is a difficult one to pursue, and it carries with it plenty of challenges - after all, it consists of taking long image exposures of extremely dim, distant, and moving objects.
In order to understand what that means, you need to understand a little bit about what I've come to learn about the night sky. In brief, it rotates. We know that the sky itself isn't moving, but instead, the earth is rotating -- which creates the illusion of a rotating sky. The sky appears to rotate around a fixed point, called the 'celestial pole.' Everything in the night sky moves on imaginary fixed rails which circle the pole at different distances. Polar aligning the telescope is the process of pointing one of its axis at the exact celestial pole, so that when the scope rotates it can follow the track of and 'freeze' any object in the night sky, which is critical to taking images.
I've managed to do this manually, but it has been difficult because even a degree or two off of the pole will result in poor tracking of objects. It's a process I will continue to improve.
Another important thing that I've had to understand is the concept of a long exposure image. During normal photography, the shutter is held open for only a fraction of a second because the sensor is flooded with light photons and can easily create a clear image. In astrophotography, though, the shutter must be held open for dozens of seconds at a time -- even sometimes minutes-- in order for the camera sensor to collect enough tired and distant light from celestial objects to form an image. The job of the telescope is to collect and focus those sparse photons onto the camera's sensor.
While the shutter is open, the apparent movement of the sky can cause the object in focus to drift to a different location and can cause the subject to 'smudge' or blur in the final image. To eliminate this, I am using an Exos-2 tracking mount, a PMC-8 (precision mount controller), and the ExploreStars software. ExploreStars sends wireless signals to the PMC-8, which plugs into the Exos-2 mount, which physically moves the telescope very slowly to hold the object in place as it drifts across the sky. All of these, together, allow me to take accurate, long exposure shots of the sky.
Although I am very proud of my progress to date, I will continue to improve and go for longer exposures, better alignments, and better tracking so that I will soon be able to capture the real gems - deep sky galaxies and nebula. (THEN you'll really see what we have in mind for my work and my mom's!) Important next steps include replacing my finderscope with an autoguiding system. What's that, you ask? Stay tuned for the next post!
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