Most nebulae, star clusters, and a handful of nearby galaxies are all well within the reach of a backyard instruments with focal lengths of around 1,000 mm or less. Higher magnification spreads the light out, making for a much fainter signal that takes longer to properly expose. Pushing your image scale too far only yields faint and blurry images.įor deep-sky targets however, you can't just continue to magnify your image of the sky or use smaller pixels to get increasingly higher resolution and scale. They are versatile systems for the visual crowd, and they can make great imaging scopes for lunar and planetary work when employing lucky imaging techniques with a high-speed camera. For these telescopes, the eyepiece controls the magnification, as opposed to focal length alone with your camera placed at the focal point of the instrument. There are many compact, long-focal-length telescopes on the market for visual observers (think Schmidt-Cassegrains and Maksutov-Cassegrains). Long focal-length, deep-sky astrophotography (starting around 2,000 mm) is best done from outer space, or when you're well along the challenging learning curve. To put it another way, buying a large telescope to start out in astrophotography is like trying to swim the English Channel after one swimming lesson. A modest, budget-minded mount can still perform quite well with a small telescope that has an equally modest focal length. The smallest errors in polar alignment, defects in mount mechanics, and other variables make accurate tracking with a large scope far more challenging. Large apertures and long focal lengths mean you need a camera with large pixels to avoid oversampling. More importantly, it places greater demands on your mount and imaging system. But while a large telescope gathers more light than a smaller one, the larger instrument is harder to use.įor one, it's heavier and harder to move around. Yes, there's something quite satisfying about purchasing a large and impressive-looking telescope. I've often encountered amateurs who buy the largest telescope they can afford right out of the gate. One of the best routes to quick success in astrophotography is a simple sky tracker with a DSLR mounted on it. This is the same regardless of how much or how little you invest in your equipment. Like any technical pursuit, astro-imaging takes some practice to master, and from the start you need to have realistic expectations of what can be done with your equipment. They have the same misconceptions about deep-sky astrophotography and even make the same mistakes. It doesn’t matter how good the gear is, we all start at the same skill level.īoth of these groups come in blind. Those who can afford it assemble the highest-quality imaging system they can buy - but they will have the same learning curve as anyone else. Buying the biggest telescope you can afford is the worst way to get started in astrophotography! (Pictured: The author at work, promoting a big setup.)Īt the other extreme are those who try to climb Mount Everest by buying a ride on a helicopter. These people are true believers in what they do and demonstrate time and again that the skill of the artist is often more important than the quality of their tools. These people work hard to adopt good practices, learning to image with whatever gear they can get their hands on. A good number do as much as they can with minimum investment, often driven by economic realities. The spectrum of people entering the hobby of astrophotography span two extremes. Although this is my 39th monthly Imaging Foundations blog, if you are interested in getting started in deep-sky astrophotography, this might be the very first installment you should read!
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