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Telescope eyepieces determine both magnification and field of view for visual observing. In most cases an eyepiece contains more optical elements than the telescope itself. A carefully chosen eyepiece set will help to maximize the enjoyment of your telescope. Quality eyepieces will maximize telescope performance by allowing it to reach its full potetial. While most eyepieces will perform well in the slower f/10 focal ratio of a Schmidt-Cassegrains, many will not perform well with f/6 faster optics common to Newtonian reflectors and today's apochromatic refractors.

The table below displays popular brand eyepieces from TeleVue, Explore Scientific, Orion and several others. This is a long page, so please be sure to scroll all the way to the bottom.

Celestron Omni Plossl

Celestron Omni Plossl eyepieces feature blackened lens edges and a multi-layer coating on each lens surface to maximize light transmission and contrast.

Celestron X-Cel LX

Celestron X-Cel LX eyepieces offer excellent value with premium features such as a 60 degree apparent field and long eye relief without a premium price.

Explore Scientific 82 Degree

Explore Scientific 82 Degree eyepieces represent a value priced option in the ultra wide field eyepiece market.

Explore Scientific 92 Degree LE Series

Explore Scientific 92 Degree LE Series eyepieces combine a wide apparent field with long eye relief for a comfortable and immersive viewing experience.

Explore Scientific 100 Degree

Explore Scientific 100 degree series eyepieces are an economical yet high quality alternative to the TeleVue Ethos.

TeleVue DeLite

DeLite is the latest eyepiece development from Tele Vue Optics, featuring 62 degree apparent fields of view and an impressive 20mm eye relief.

TeleVue Delos

TeleVue Delos eyepiecesoffer exceptional contrast combined with 20mm eye-relief and a 72 degree apparent field.

TeleVue Ethos

TeleVue Ethos is the world's first fully-corrected 100 degree astronomical eyepiece.

TeleVue Nagler

TeleVue Nagler eyepieces provide a tack sharp image across an extremely generous 82 degree apparent field. Shop our inventory of Nagler eyepieces now!

TeleVue Panoptic

TeleVue Panoptic eyepieces offer a wide 68 degree apparent field and have been a long time favorite for low to medium power observing.

TeleVue Plossl

TeleVue Plossl eyepieces use superior high-index glasses to reduce astigmatism and lateral color at the field's edge.

Zoom Eyepieces

Zoom eyepieces are popular for lunar and solar observing because they allow you to quickly zoom in on a specific feature without changing eyepieces.

Barlows and Image Amplifiers

Barlows and image amplifiers are placed between the telescope and eyepiece to produce more magnification from that eyepiece.

Specialty Eyepieces

Specialty eyepieces are not used for observing, and include those that are used for collimation, guiding, or assisting with precise go to alignment.

Eyepiece Sets

Eyepieces sets can be an economical way to get started provided that the focal lengths of the eyepieces are a good match for the telescope.

Telescope Eyepieces for Astronomy

A telescope collects light and converges those light rays to a focal point. The eyepiece takes over from there, forming the image you see. The eyepiece also determines both the magnification and the true field of view that you see, which is why different eyepieces are needed to observe different objects. Eyepieces have a far greater impact on your observing experience than any other telescope accessory.

Eyepieces are complex devices, usually containing more optical elements than the telescope itself. A carefully chosen eyepiece set will help to maximize the enjoyment of your telescope, but you must carefully choose them based upon the types of objects you plan to observe. Four major factors to consider include:

  • Magnification: Eyepieces determine the magnification at which you view a celestial object. While most people think the higher the magnification the better, this isn’t always true. For example, high magnification might be a good choice for viewing an individual planet, but would be a poor choice if you wanted to see an entire nebula. Since the field of view decreases with magnification, the higher your magnification, the less of the night sky you can see in a single view.
  • Field of View: Magnification and field of view are largely linked — the higher the magnification, the smaller the field of view. Some eyepieces offer larger fields of view at the same magnification, allowing a larger object to be seen within the field. Field of view is important to consider when viewing larger objects, like the Orion Nebula or the Andromeda galaxy.
  • Exit Pupil: This is perhaps the least understood yet most important consideration when choosing eyepieces.  Exit pupil is the diameter of the light cone leaving the eyepiece at the point where the image is formed.  It is calculated by dividing the eyepiece focal length by the telescope focal ratio.  The human eye can accommodate up to a 7 mm exit pupil; anything larger is a waste.  There are also practical considerations on the lower end of the exit pupil spectrum.  In simple terms, an exit pupil of 2 mm or larger tends to be best for viewing deep space objects, whereas an exit pupil of 0.5 to 1 mm is generally best for observing the planets.

So how do you determine the magnification of an eyepiece? The focal length of the eyepiece is the most important number — this is given in millimeters on the side of every eyepiece. Simply divide the focal length of your telescope by the focal length of your eyepiece to determine the magnification you’ll achieve. The lower the number on your eyepiece, the higher the magnification you’ll get overall.

Where to Buy Telescope Eyepieces

At Skies Unlimited, we offer quality eyepieces for telescopes from several brands, including TeleVue, Celestron, Explore Scientific, Orion and others. The list is long, so please be sure to scroll through the entire page to see the full stock of telescope eyepieces for sale.

We also offer advice on how to select the best telescope eyepieces for your application and how to use them properly. Call Skies Unlimited today or visit us at our Pottstown, Pa., location to speak with a staff member and determine the best eyepiece choices for your celestial viewing experience. Visit Skies Unlimited to buy telescope eyepieces today!