Getting started stargazing is easy, but there are some helpful hints to know
in order to make using your telescope easier. The other pages of the
Telescope section give specifics on polar alignment, balancing, and aligning a
computerized telescope, as well as more advanced techniques such as collimating
and cleaning optics. Below you will find some tips on doing the basics to
get a telescope up and running.
Aligning a Finderscope
After putting your new telescope together, but before you can use it, you
will need to align the finderscope with the main
telescope. Once this is done, whatever you aim to with the finderscope will be visible in the main scope.
There are two basics types of finderscopes: optical finders and
finders. An optical finder is just a small telescope with a set of
crosshairs, like a riflescope. The main drawback to optical finders is
that they normally present an image that is upside-down and backward.
Reflex finders, like the popular
Telrad, project a red dot or bulls-eye onto a small piece of glass.
The result is that the dot or bulls-eye appears to be up on the sky.
Reflex finders have no magnification and do not flip the image, so they tend to
be much easier to use.
The easiest time to align a finderscope is during the day. Begin by
pointing the telescope at a distinct target at least a few hundred yards away.
Telephone poles, treetops, and mountain peaks are all good choices. Just
make sure you know what object you are aimed at. Next, look through the
finderscope and see where it is pointed. With an optical finder, there are
normally three small screws that must be adjusted to align the finder.
This can be a little tricky if everything is upside down, but a little trial and
error will determine which way the screws need to be turned. With a reflex
finder, things are usually easier since the image is correct. Depending
on the type of finder there will usually be two screws for up and down, or three
screws that move the target at angles.
Above: A prominent target centered in the
eyepiece (left) and in the finderscope crosshairs (right)
Always be sure to check the view through the main telescope when finished
with the finder to be sure the telescope did not get bumped during the alignment
Using a Finderscope
Once the finderscope is aligned, you can use it to find objects in the night
sky. For some objects like the moon and planets, this is pretty easy.
With an optical finder, it takes some time to get used to the inverted image,
but pretty soon you should be able to quickly point to bright objects.
Finding bright targets with a reflex finder is even easier. But the real trick is
hunting down objects that are not visible in the finderscope. To do this,
you must use a chart and a technique called starhopping. This is much
easier to do with a reflex finder since it does not magnify the sky or change
the view you have of the stars. (Trust us on this one, adding a reflex
finder to your telescope is the best thing you can do to make your stargazing
simpler!) But starhopping with an optical finderscope is not terribly hard with
Suppose you want to find the Whirlpool Galaxy, M51. This object is too
faint to see through most finderscopes, and is invisible to the unaided eye.
Consulting a basic star chart shows that M51 is located near the end of the
handle of the Big Dipper. Imagine the angle and distance from the last
star in the Dipper's handle to the galaxy. With a reflex finder, things
are easy: just aim the red dot or bulls-eye to that area of the sky, and
with a low-power eyepiece you should see the galaxy in the telescope. With
an optical finder, it is harder to tell exactly where you are in the sky because
you lose the reference stars you can see with the unaided eye. The trick
now is to look for recognizable patterns in the finderscope that correspond to
patterns seen on the star chart. Of course, you must remember the image
through the finderscope is upside-down and reversed relative to the chart.
(Have you ordered your reflex finder yet?) Once you identify some patterns
in the area of M51, you can tell which way to move the telescope to aim to the
right part of the sky.
Above: Finding a deep-sky object with a
Above: Finding a deep-sky object by
starhopping with an optical finder. In this case, you might begin by
finding the relatively bright star below the last star in the handle of the Big
Dipper. Then moving down and left would take you to a distinct pair of
stars. A small move up and left will find the target.
New stargazers often underestimate the importance of focusing the telescope,
especially when a group of people is viewing. Everyone's eyesight is
different and each observer should focus the telescope for her own eye.
Eyeglass wearers may be able to remove their glasses to view. Adjusting
the focus of the telescope will compensate for nearsightedness or
farsightedness. It will not, however, correct astigmatism, so observers
with this eye aberration will have to keep their glasses on. Just a small
difference in focus can make a big difference in image quality. Be sure to
focus each time you look, and have your guest stargazers do the same. Many
people are hesitant to touch someone else's telescope, so be sure everyone
viewing knows it's okay to adjust the focus.
Moving a Telescope Around the Sky
Pointing a telescope where you want in the sky is not always straightforward.
With an alt-azimuth mounted telescope, such as a
Dobsonian, the movement is
intuitive: up-down and left-right. But with an equatorial mount, getting
the telescope aimed can be trickier. With a German equatorial mount, one
axis (the polar axis) of the mount always points north. Imagine the sky
divided into two halves on either side of this axis, east and west.
Beginning with the telescope in its "home position" pointing north over the
mount axis, you can simply move the front of the telescope to the half of the
sky you want to see. This is tricky for objects in the south; it is
easiest to stand to the north of the mount and look over it to see if the object
is east or west of the polar axis. The other trick is getting from one
half of the sky to the other. Always bring the telescope back through
north to switch sides of the sky. This will keep the scope from flipping
Transporting a Telescope
A telescope contains delicate optics and transporting it should be done with
care. While a protective carrying case is recommended, it is not always
necessary. A scope can handle a little bouncing around as long as it is
padded. Many people will simply wrap a telescope in a blanket and buckle
it into the back seat to drive out to a star party. This works especially
well with larger Schmidt-Cassegrain telescopes, which are the perfect size and
shape to sit in a car seat. Hard cases offer the best protection and can
carry accessories in addition to the telescope itself. For larger
telescopes, cases often have wheels, making it easier to move things around. If you plan on taking your telescope overseas or somewhere requiring a flight,
it is recommended that you ship the telescope to meet you rather than put it
onto the airplane. This is because you can insure a telescope when
shipping it, but not usually when you transport it on an airplane. Not to
mention that, as rough as they are, shippers are still gentler than baggage
handlers. If you have to transport by plane, use the telescope's original
shipping container rather than a case, and sit on the side of the airplane
opposite the cargo doors so you don't have to see what's happening to your
Storing a Telescope
Where and how you store a telescope is very important. We have had
customers bring in telescopes that were full of water or looked like they were
unearthed from an archeological site. Don't let this happen to your
telescope's optics and electronics by following a few rules. First, don't
store a telescope outside. No matter how protected you think it is under
your patio, dust and water have a way of getting into the most amazing places.
If you know the weather will be good (and trust us, you never know, and neither
does your local meteorologist), you can keep a telescope in a protected area
outside when you plan on using it frequently. But if you know you will not
use a telescope for a few days, it is best to bring it inside. Don't
listen to anyone who tells you otherwise, a telescope looks great in a living
room. It's a wonderful conversation piece. No one will ask you about
the philodendron bipinnatifidum growing in the corner, but everyone will
inquire about your telescope.
Heat can also affect a telescope, especially the electronics and the drive
motors and gears. The grease on the gears in a telescope mount can
evaporate in high temperatures, so try to avoid direct sunlight, especially in
hot environments. It seems obvious, but keep the telescope optics covered
when you are not observing, and keep all the openings to the telescope (such
as the focuser or visual back) capped when not in use to prevent dust and dirt
and spiders and moths and other critters (trust us, if it fits, it will find a
way in there) from finding a happy home inside your telescope.
The following are some of the most common problems new
stargazers run into and the fixes for those issues.
I Can't See Anything Through the Telescope
One hates to overstate the obvious, but more than a few
people have forgotten to take the cover off the telescope. Assuming this
isn't the problem, the questions becomes, what is? The best test is to
look through the telescope during the day. As Han Solo says in Return
of the Jedi, "I think my eyesight is getting better. Instead of a big
dark blur, I see a big light blur." So the question is do you see a big
light blur through your telescope? If so, that is--as Captain Solo has
pointed out--a step in the right direction, and you can skip to the next
troubleshooting section below. If everything is still dark, be sure there
isn't a cap on the inside or the eyepiece or diagonal that it blocking the light. A
common mistake is also to try looking through a Newtonian reflector backwards.
Remember, if your telescope is a Newtonian (the eyepiece sticks out the side of
the tube), the eyepiece end points toward the sky.
Everything Is Blurry Through the Telescope
If you can see something through your telescope, but it is
just a big amorphous blob, there is at least light coming through, which is a
good first step. If you are testing your telescope during the day, be sure
it is not pointed at something too close. The closest most telescopes can
focus is about 30-50 feet away. Also, keep in mind that on some
telescopes, especially Schmidt-Cassegrain telescopes, the focus travel can have
quite a range. You may have to turn the focus knob 20-30 times to reach
focus. If these steps don't work, be sure there are no other accessories
between the eyepiece and the telescope (other than a diagonal, if required).
Some inexpensive telescopes include Barlow lenses that, if installed in the
wrong place between the eyepiece and scope, may prevent the telescope from
The Image is Upside-Down
There are three possible causes for this. One, the
image is rightside-up and you are upside-down, but this should be apparent (one
would hope). Secondly, you could have a
Newtonian telescope. A
Newtonian has the eyepiece sticking out the side of the tube, near the front of
the telescope. This type of telescope is ideal for stargazing, but does
give an inverted image, making terrestrial viewing difficult.
Unfortunately, there is really no fix for this--except standing on your head
(see cause number one). Lastly, a telescope such as a
Schmidt-Cassegrain can give a correct image for terrestrial viewing.
However, if the diagonal is rotated so the eyepiece is horizontal, the image
will flip. The eyepiece must be kept straight up and down for the image to
The Telescope Won't Stay Still
A well-built telescope should stay put when you aim it
somewhere. Some inexpensive models tend to be a bit wobbly, and
unfortunately there isn't much you can do about this (other than upgrading to a
better scope). For telescopes that should hold still but won't, the most
common problem is balance. It is critical to properly balance a telescope
for stability and tracking. If you point a telescope to one part of the
sky and it slowly drifts from that position, odds are it is unbalanced and extra
weight is pulling it out of alignment. See the page on
Telescope for more details on this procedure.
In addition to slowly drifting, a telescope may vibrate
excessively. Again, this shouldn't be too much of a problem with a good
quality telescope. Setting up on a stable surface is important.
Decks and flat rooftops make convenient places to observe from, but they tend to
Vibration suppression pads are made to be placed under the
tripod legs of a telescope to dampen vibration. Also, adding weight to a
tripod can help stabilize a telescope. Try hanging a weight from the
center support of the tripod, or filling the tripod legs (if you can get to the
inside) with sand.