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Telescope Should I Buy?
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Like all amateur astronomers, I'm constantly asked by friends and colleagues
which telescope they should buy. As with many apparently simple questions,
there's no simple answer ???
Basically, there are three types of telescopes, each of which has numerous
- Refractor - ??? Mainstream refractors sell at prices ranging from $100 to
more than $25,000, depending on size and quality.
- Reflector - ??? Mainstream reflectors sell at prices ranging from $100 to
$25,000, again depending on size and quality.
- Catadioptric - ??? Mainstream catadioptrics sell at prices ranging from
$1,000 to about $10,000, depending on size. Quality varies much less with
catadioptric scopes. Nearly all cats are made by Meade or Celestron. There
are a few very low production volume cats made by premium manufacturers like
Ceravolo, Takahashi, and Questar that cost much more..
Broadly speaking, there are two types of telescope mount:
- Altazimuth -
- Equatorial -
A Word about Astrophotography
Many people who are considering adopting astronomy as a hobby think that
astrophotography may be for them. If you are thinking that, I suggest you think
again. Although you can do casual astrophotography of the moon and planets with
inexpensive scopes, you're likely to be disappointed in the results. For any
kind of serious astrophotography, a realistic minimum is an 8" SCT with
good drives and a very solid mount. With the accessories you'll need for
photography, that scope will set you back at least $2,000 to $2,500, and even
that is an absolutely bare minimum. Most people who are seriously into
astrophotography use kit that costs at least $5,000, and $10,000 is more common.
An interest in astrophotography has probably been responsible for more people
giving up the hobby than anything other than junky department-store scopes.
Because many newbies think they might be interested in astrophotography, they
end up buying scopes that are less suitable for visual observation than they
might have bought for the same money, and those scopes turn out not to be
suitable for astrophotography anyway. If you believe one thing you read on this
page, believe that there is no cheap way to do serious astrophotography. Period.
Unless you have a very large budget and are certain that astrophotography is
something you want to do, completely ignore the idea of doing it. That way,
you'll avoid buying a compromise scope and instead get something that's better
suited for visual observation, which is what you really need.
Specific Recommendations by Budget
??? A lot of recommendations by budget level consider only the cost of the
scope, ignoring even shipping costs, which can be substantial. Others ignore the
need for at least some accessories, the price of which can add up. I'll also try
to keep in mind that what's a lot of money for one person might be pocket change
for another. On the Internet astronomy mailing lists I follow, most pleas from
newbies for help selecting their first scopes specify a budget of $500 to
$1,000, which is realistic. But larger budgets aren't all that uncommon. Many
well-to-do folks spend $2,000, $5,000 or more on their first scope--which
certainly buys them more scope than those with a lower budget--and one guy ended
up spending $30,000 on his very first scope. I won't try to address the needs of
folks with very large budgets, because I don't have that much money to spend on
astronomy gear. But I will try to give reliable advice for those with more
A lot of people make the mistake of buying a go-to scope. The idea of a scope
that will find objects for you is very attractive, certainly, but there are
major pitfalls with this approach:
- First and foremost is that with a go-to scope under $1,500 or so, you're
putting much too large a percentage of your money into fancy electronics at
the expense of optics size and quality and mount stability. Without a solid
mount, the best optics in the world are useless. Without good optics, the
best go-to system in the world is similarly useless.
- The second problem is that go-to systems, particularly inexpensive ones,
are not very reliable. They're mechanically fragile, prone to failure
- The third problem is that go-to systems aren't quite as simply as their
makers would have you believe. ???
- The fourth problem is a philosophic one. Using a go-to system is kind of
like paying Tiger Woods to write your name on his score card at the country
club tournament. You'll certainly end up with a better score, but there's
sense of accomplishment, and you're never going to become a better golfer if
you do things that way. And, just as your golfing buddies might rightly
consider this to be cheating, so your observing buddies might rightly
consider using a go-to scope to be cheating.
Do not buy a telescope. Buy a decent binocular, a book or two, and a red
flashlight. That's enough to get you started, and you won't be wasting your
money if you do later decide to buy a scope. Essentially all serious amateur
astronomers use binoculars as well as scopes.
The interesting thing about binoculars versus telescopes is that the quality
and usability varies much less with binocular price than with telescope price.
Even inexpensive binoculars Wal*Mart can be useful instruments for astronomical
observing, although I suggest that you spend a bit more than the least expensive
models sell for. On the high end, you can easily spend $1,500 or more for
binoculars made by Leitz, Zeiss, Fujinon, and other premium makers. Those
binoculars are superb, both mechanically and optically, but you give up
surprisingly little if you spend only 5% to 10% that amount.
On to specifics. If you want to get into astronomy and your budget is less
than $300, I suggest you buy the following items:
- Binocular -- Other than optical and mechanical quality, there are
three important aspects of binoculars: magnification, objective lens size,
and field of view. Some would add "exit pupil" as a fourth
important characteristic, but that's determined by dividing objective size
by magnification. Binoculars are designated by magnification and object
size. For example, a 7X50 binocular magnifies seven times and has 50mm
objective lenses, whereas an 8X42 binocular magnifies eight times and has
42mm objectives. Field of view is determined by the optical and mechanical
design of the binocular, and may be specified either in degrees or in the
number of feet visible at 1,000 yards.
For those on a budget, I recommend the Orion
Scenix Binocular. These binoculars are available in several sizes,
including the 7X50 and 10X50 models that are most appropriate for astronomical
use. Although the 10X50s are probably more popular than 7X50s among
astronomers now, Barbara and I both use 7X50s because they're more comfortable
to use. Not only are 7-power binoculars easier to hand-hold than 10-power
binoculars, but the oversized 7mm exit pupil of the ??
- Red flashlight -- you need one of these to preserve your night
vision while observing. If you're on a tight budget, you can make your own
from a standard penlight by using several layers of red cellophane or some
red nail polish to get the light down to a dim red glow. The special LED
flashlights made for astronomy are a lot more convenient however. My
favorite is the Orion
RedBeam™ II LED Adjustable-Brightness Astro Flashlight.
- Books -- There are three books frequently recommended for beginning
astromomers. Two of them are general introductions to astronomy and the
night sky, and you'll want to have one or both of them. The first is Night
Watch, by Terence Dickinson and the second is Turn
Left at Orion, by Guy Consolmagno and Dan Davis. I have no
preference between the two. They are both excellent. Check them out at your
library if you want to look before buying. The third book is specifically
targeted at binocular observers, and is also superb. It's Touring
the Universe with Binoculars, by Phil Harrington. If you buy only
one book for binocular observing, this is the one to get.
- Observing Aids -- Beginners are always frustrated because it's hard
to find things. It's enjoyable to just to scan around with your binoculars
and see what you can see, of course, but it's even more fun to decide what
you want to look at and then find it yourself. The books I recommended above
are helpful in that respect, but there are some inexpensive aids that are
even more helpful in finding things:
- Planispere -- These little $10 items are a very useful aid to
learning the night sky and finding objects. You just dial in the date
and time, and the window displays what the night sky will look like.
Orion sells a very nice planisphere called the Orion
Star Target Constellation & Celestial Object Finder.
- Star Map -- Once you get seriously involved in astronomy,
you'll probably want books with detailed star charts. But for someone
who's just getting started or needs a quick reference to locate a
prominent object, the roadmap-size Orion
DeepMap 600 is a wonderful aid. It's plastic coated (so dew won't
soak it) and folds up just like a standard roadmap.
- Planetarium software -- ???
$300 to $500
$500 to $800
$800 to $1200
$1200 to $1800