Find out first
Learn everything you can about telescopes. Include advertisements from manufacturers, and especially read reviews of the telescope. Do not proceed to the next step if you are not familiar with telescope reviews. Astronomy magazine is a great tool for viewing telescope advertisements and reviews.
Avoid any telescope that touts its magnification. Claims of 500X magnification for telescopes make no sense, and here’s why: The maximum magnification a technician can use to keep the image sharp and clear is called useful magnification. (not the maximum magnification), the useful magnification of a telescope is calculated by multiplying the lens size or lens diameter of the objective lens in inches by 50 (or multiplying by 2 if measured in mm). Therefore, a 4-inch telescope provides useful magnification of up to 200x. So an 8-inch telescope has a maximum useful magnification of 400x. If you require a telescope with a magnification higher than the useful magnification, you must accept that the resulting image quality will be low.
Try before you buy
Are you really serious about purchasing a quality telescope? If so, try to observe which ones you want to consider. The easiest way to do this is to call or visit local astronomy clubs. Find out when they have a shadowing session and attend it. Try to look through as many telescopes as possible and ask as many questions as you can imagine. Find out about assembly time, maintenance, accessories and costs. If you can’t find an astronomy club nearby, call or visit a local planetarium. The staff will direct you to astronomy clubs near you.
Find a reputable dealer
A salesperson at the dealership will advertise the telescope a little to all buyers. A seasoned salesperson will ask you a few questions to determine your level of expertise and interests. A good salesperson will not try to sell you more telescopes than you need. In Vietnam, HAS Astronomy Store sells famous telescopes that many people trust and guarantee their prestige. You will be guided and guaranteed absolute confidence.
Buy a giant telescope
OK, just kidding, but I want to clarify something. With telescopes, two seemingly contradictory rules apply: the larger the telescope, the better; The smaller the telescope, the more often you will use it. The only time this second rule doesn’t apply is if you want to build an observation station. A 10 inch telescope will be better than an 8 inch, and of course it will be better than a 6 inch telescope, etc. But it will be less tiring to install a small telescope on a simple support. a large reflector on a heavy and bulky support.
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