My First Scope
There’s no single “best” telescope, which keeps things interesting. Choices depend on factors like price, complexity, size, and quality.
Where to Start
- Your Eyes and a PlanisphereLearn the constellations and the Moon first.
- BinocularsWide views, and much less expensive.
- Then a TelescopeLook through ours before you buy one.
Start With Your Eyes
Of course, the hobby can be enjoyed without telescopes, and many times the answer is to enjoy the constellations and the moon without an observing aid, or to begin with binoculars that are usually much less expensive, but still can bring the wonder to our eyes.
You might well want to start with a planisphere and a good sky atlas, like Sky and Telescope’s Pocket Sky Atlas.
Beginners often ask for help choosing from the many guides to the night sky. There are few better places to start than Nightwatch by Terence Dickinson. Another such resource, aimed at those who want to find objects with a Dobsonian and a finder, is Turn Left at Orion by Guy Consolmagno and Dan Davis. These books are available to members in our library.
Binoculars
Binos are a great way to learn the sky: with their wide views, you can take in large parts of constellations, sweep Milky Way clouds, and even see many Messier objects, such as globular clusters.
Astronomy binoculars generally have 50mm or larger objectives (the second number in a 7×50 description), and prices have come down lately. Heavier models, or those with higher magnification, will require a tripod.
When You’re Ready for a Telescope
Most first time buyers usually look at 6″–8″ Dobsonians. If you want to know how a Dobsonian will work, make sure you attend a public or member night at the AEC. During public nights, we try to set up our Dobsonians on the observing platform for use.
The old adage is the best telescope is the one you use, and one that is easy to carry or transport will be one you use more often.
Our club does not endorse any vendor or any manufacturer. A good source for used equipment is Astromart.
450× Magnification or More?
Avoid telescopes advertised by magnification, as they are likely low-quality. Never purchase from malls, department stores, warehouse clubs, or TV. These tend to be disappointing and a waste of money. Be cautious with Craigslist; most listings are likely subpar.
How Large of a Telescope Do You Really Need?
A smaller backyard telescope wins by default over a big one you didn’t bother to set up. While some argue you can never have a telescope that’s too big, it doesn’t always make the larger one better. Large scopes can’t do wide fields of view, which is important for large objects. That’s why many stargazers have more than one telescope.
Consider portability as well: How heavy are the parts, and how easy is it to set up and store? Telescopes that are too large or heavy tend to be used less frequently.
Most stargazers end up with multiple telescopes, each with its strengths. Small, non-computerized telescopes are perfect for quick backyard moon and planet viewing. Some are easily portable, making them convenient for regular use. Larger, computer-controlled telescopes are heavier and break into sections, requiring more effort to set up.
Refractor, Reflector or Catadioptric
Refractor
This is what most people think of when they hear the word “telescope”. Modern glass has vastly increased this design’s desirability but only at the higher end of the price scale. A quality refractor is usually on every astronomer’s wish list.
Advantages Potential for the best images, no obstruction in light path.
Disadvantages The most expensive of the three designs per inch of aperture (often by a large margin). Some secondary color (“chromatic aberration”) is visible in all but the best units. Large aperture instruments are massive.
Reflector
Invented by Sir Isaac Newton to fix the refractor’s issues with chromatic aberration. Uses a parabolic mirror instead of a lens to focus light.
Advantages Most economical of the three designs per inch of aperture (especially those on Dobsonian mounts).
Disadvantages Secondary obstruction results in some loss of contrast. Can require occasional collimation (alignment) of optics.
Catadioptric
Schmidt-Cassegrain, Maksutov-Cassegrain, Schmidt-Newtonian are all Catadioptric designs that use both mirrors and lenses to fold the optical path back onto itself resulting in a compact design. The Schmidt-Cassegrain telescope is the most common variant and is referred to as an “SCT.”
Advantages Most compact per inch of aperture of the three designs.
Disadvantages Images are typically the worst of the three designs.
Aperture, Focal Ratio, Mounts
Size (Aperture)
The larger the aperture the more light you can gather and the dimmer the object you can see. If you plan on looking at the faintest objects like dim nebula and distant galaxies far from the typical suburban light pollution, then you want to consider looking for the largest aperture telescope you can afford. However, if you are concerned about the size and weight, then huge isn’t for you.
Focal Ratio (f/Number)
When comparing scopes of equal aperture, the smaller the f/number, the wider the field of view.
f/4–6Low power, wide field
f/7–9A good compromise
f/10–15Lunar, planetary, binary stars
Focal ratios of f/4 to f/6 are best for low power wide field observing. Focal ratios of f/10 to f/15 are better suited to higher power lunar, planetary, and binary star observing. Medium f/7 to f/9 focal ratios are a good compromise to allow both fairly well.
Telescope Mounts
The telescope’s mount is crucial for your experience. There are two main types: Alt-azimuth and Equatorial.
- Alt-azimuthRequires constant adjustments due to Earth’s rotation. The Dobsonian, a reflector telescope, is a popular example without motors or computers, making it a good choice for beginners and experienced users alike.
- EquatorialMounts align with Earth’s rotation axis for easier tracking. They were the first to feature “clock” drives, and later, computer systems for precise targeting.
Go-To or Not to Go-To
Even budget telescope mounts now come with “Go-To” technology, driven by a computer and motors for precise targeting. This may seem ideal, but it’s complex. Initial alignment requires knowledge of brighter stars’ names and locations, aided by star charts or astronomy apps. Don’t assume it’s easy just because it’s computer-driven; it takes effort to set up correctly.
Advanced mounts offer Go-To with GPS and self-aligning cameras but come at a cost, requiring time to master. Some stargazers prefer manual “star hopping” to locate objects, finding it more satisfying than relying on a computer. It’s a different, rewarding experience.
For mounts without Go-To, you can add Digital Setting Circles, often used on large Dobsonian telescopes, assisting in finding deep sky objects, sometimes called “push-to” scopes.
Eyepieces
Eyepieces are crucial for a telescope’s field of view and magnification. Quality matters, as even a fine lens or mirror won’t perform well with a subpar eyepiece. Three or four carefully selected eyepieces are sufficient.
Eyepieces vary widely in price ($25 to $800) due to complexity. Balance price, performance, and quality. Expect to pay more for wider fields of view, better eye relief, and higher-quality glass. Don’t buy a $700 eyepiece for a $300 telescope when an $80 one can work just as well. If you wear glasses, look for eyepieces with good eye relief.
Don’t focus solely on high magnifications; they’re rarely usable due to sky conditions and can make objects appear dimmer. Lower power, wider field eyepieces are used most of the time.
Resolving Power
The telescope’s diameter also affects its resolving power, but this assumes perfect optics and seeing conditions. Interestingly, in bad seeing, a small telescope can sometimes resolve more than a large one because it catches less turbulence.
Later On
Astrophotography
A beginner getting into astrophotography is like wanting to enter the Indy 500 without knowing how to drive. It’s a big endeavor, requiring a substantial investment. While smartphone attachments can capture basic images, true astrophotography is much more complex and expensive. It involves specialized equipment, software, and significant time investment, especially in light-polluted areas. If you’re still determined, thorough research and possibly building an observatory in dark skies are crucial. It’s a serious commitment.
Video Astronomy
Light pollution limits suburban stargazing, but the NAA has an observatory with video astronomy that shows deep sky wonders in color. You can also watch live sessions on Night Skies Network where amateur astronomers broadcast their live viewing sessions using Mallincam cameras. You can get a better idea of what is possible by watching and asking questions.
Video astronomy is simpler than astrophotography, but it’s not for beginners. Video astronomy uses a special camera, in place of an eyepiece, connected to a screen. It’s better than our eyes – with sensitivity and exposure control, so fainter objects can be seen in light-polluted skies.
Video astronomy requires a special camera, a sturdy mount, and a short focal length telescope. Sometimes a computer is needed. Low-priced cameras work for the moon, but colorful deep sky objects need more expensive equipment.
Watch Our Members Explain It
Look Through a Few Before You Buy
We host free Public Nights at our Astronomy Education Center all year ‘round.