![]() ![]() Since these objects are so faint, the eye doesn't see a whole lot of high-resolution detail, so they are not affected by seeing (as far as the human eye is concerned). One second of exposure to a bright light destroys a dark adaptation that took 20 minutes to build. And turn off that flashlight and keep it off. Street lights 500 meters away are too bright. Even the screen of your phone is far too bright. It's important that your eyes are adapted to very deep darkness when observing these things, so stay away from any source of light. ![]() In any case, you should be able to observe the whole Messier catalogue (over 100 objects) from the city - but out in the boondocks these things look better. But many of them look much, much better away from light polution. Anyway, just stay away from city lights and the view will improve.Ī few of these objects will be visible from the city: the Andromeda galaxy, the M13 cluster, the Orion nebula, etc. This is pretty hard to do in Europe in the US, population density is low and this is somewhat easier. You need to take your scope far and away from any city, town and industrial complex (at least a 1 hour trip at highway speed). These objects are affected by light pollution. In a very large scope, there's galaxies everywhere.īut again, there's a catch. These are the kind of objects that huge dobsonians (half-meter aperture, or more) are made for. Their light is very faint, so it's essential you capture as much of it as possible. These are most of the nebulae, star clusters, and galaxies. You don't need to be in deep darkness while observing them - in fact, it's beneficial if you're not adapted to very deep darkness. You could observe the Moon from a brightly illumined parking lot in the middle of the city. These objects are not affected by light pollution. So, for high resolution targets, the point of having a large instrument (like a huge dobsonian) is because once in a while seeing is so good (turbulence is so low) that you can actually use all its huge power - but most of the time you'll be using it at much less than its theoretical power, as if it's a 4" instrument or whatever the seeing is at the moment. There are ways to forecast seeing, because it depends on weather: If your instrument is 100 mm (4") or smaller, it's not so noticeable because you don't have that much resolving power to begin with. If your scope is 200 mm (8") or bigger, this will happen A LOT. When air is turbulent, it will reduce the resolving power of your instrument. But there's a problem - seeing (the inverse of turbulence). You get more resolving power if the aperture (the diameter) of the scope is bigger. But these objects show high-resolution detail, so the resolving power of your scope is crucial. These are typically pretty bright, so the amount of light you capture is not essential. These are the planets, the Moon, many double stars, and the like. So that's the perspective you'll get.įirst off, a few words about the objects you'll observe. I'm 25% of the former, 75% of the latter kind (I make telescopes and mirrors, and I do some optics design). Hope you like that sort of thing, because it's kind of mandatory in this hobby.Īlso, there are two kinds of people in this field: those who enjoy using the instruments, and those who enjoy making the instruments. So, in a sense, it will be just the beginning of a learning journey, and you'll have to keep learning and trying things out. Be aware that you'll make the choice while still not knowing much about optics. Instead, I'm going to describe your main options, and let you choose. This is a very common question, yet very hard to answer if you prefer a clear, concise, uncontroversial answer that applies to all situations. ![]()
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