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A telescope simply will not work without an eyepiece. The optical elements of an eyepiece allow you to focus light collected by a telescope, so you can observe a sharp view of the object or area where the telescope is pointing. With an eyepiece installed in the telescope focuser, you can bring extremely distant objects into focus for magnified study.
While most new telescopes include one or two eyepieces to get started with, purchasing additional eyepieces can significantly increase the functionality of any telescope, new or old.
Let's take a few moments to learn a bit more about the most common terms and specifications used to describe features of telescope eyepieces. With this knowledge, you'll be well-prepared to select ideal eyepieces for your own telescopes.
Focal Length and Magnification
Perhaps the most important specification of an eyepiece is its focal length. The focal length of an eyepiece, along with the focal length of the telescope the eyepiece is used with, determines the magnification the combination provides.
So the first step in choosing eyepieces is to decide what magnifications, or powers, you want to use and what eyepiece focal lengths will give them. Since both eyepiece and telescope focal lengths are expressed in millimeters, the formula used to determine magnification is:
Magnification = Telescope focal length (mm) ÷ Eyepiece focal length (mm)
Or, put another way,
Eyepiece focal length (mm) = Telescope focal length (mm) ÷ Magnification
For example, a telescope with a 2000mm focal length used with a 20mm eyepiece will give 100 power (2000 ÷ 20 = 100).
The above formula dictates that a telescope eyepiece with a shorter focal length yields a higher magnification than an eyepiece with a longer focal length. For example, a 10mm eyepiece will always provide a higher magnification than a 25mm eyepiece. This relationship is important to remember while choosing eyepieces: the lower the eyepiece focal length, the higher the relative magnification will be. The actual magnification will depend on the focal length of the telescope the eyepiece is used with.
If you've ever used a single telescope at different powers, you know that you have a choice of a small, sharp, bright image at lower magnification; or a big, blurred, dim image at higher power. The reason is twofold. First, the telescope gathers a fixed amount of light, and at higher magnifications, or powers, you're spreading the same amount of light over a larger area, so the image will always be dimmer. Second, because light consists of waves, even an optically perfect telescope picks up only a limited amount of fine detail in the image. Magnifying the image beyond a certain point does not reveal more; it just makes the image look blurry. This is called "empty magnification" and can change depending on the object or area viewed.
Field of View: Apparent and True
A telescope eyepiece's apparent field of view is the angular diameter, expressed in degrees (°), of the circle of light that the eye sees. It is similar to the screen of a television (not the actual picture seen on it). Most eyepieces have an apparent field of about 40° to 50°. Specialized wide-field telescope eyepieces can boast apparent fields ranging from 60° to 100° or more. Such wide-field and Ultra-Wide eyepieces are preferred by amateur astronomers who enjoy the "spaceship porthole" effect of using as wide a field as possible.
The true field (or real field) of view is the area of sky seen through the eyepiece when it's attached to the telescope. The true field can be approximated using the formula:
True Field = Apparent Field ÷ Magnification
For example, suppose you have an 8" Cassegrain telescope with a 2000mm focal length, and a 20mm eyepiece with a 50° apparent field. The magnification would be 2000mm ÷ 20mm = 100x. The true field would be 50 ÷ 100, or 0.5° - about the same apparent diameter as the full Moon.
Eye Relief and Corrective Lenses
The optical design of an eyepiece determines the eye relief, which is the distance from your eye to the eyepiece lens when the image is in focus. If you wear corrective lens eyeglasses while using a telescope, we recommend looking for telescope eyepieces with at least 15mm, and more preferably 20mm, of eye relief to see the entire field of view comfortably. With insufficient eye relief the outer portion of the viewing field will be cut off, resulting in a "keyhole effect" which can be frustrating. In more traditional telescope eyepiece designs, eye relief is proportional to focal length: the shorter the focal length, the shorter the eye relief. However, some of the more modern eyepiece designs provide luxuriously long eye relief regardless of focal length -- a real boon to eyeglass wearers. If you like to keep your eyeglasses on while using a telescope, the eye relief of an eyepiece is a very important specification to consider.
Barrel Size
Most quality telescope eyepieces come in two different barrel diameters, 1.25", and 2". A smaller, 0.965" barrel size is found mostly on low-end "department store" telescopes and should be avoided, if possible. Most amateur telescopes are designed to accommodate the 1.25" eyepiece size. Larger 2" eyepieces are typically used with larger aperture telescopes that feature a 2" focuser. Big 2" eyepieces traditionally feature long eye relief for comfortable views, and they often offer wider fields of view compared to 1.25" eyepiece models.
Optical Correction
The main goal of any telescope eyepiece design is to get all the light rays collected by the telescope to form a sharp image. Depending on the f-ratio of the telescope, this can be a difficult task. Telescopes with low f-ratios require more highly corrected eyepieces because the cone of light entering the eyepiece is converging more sharply. With a relatively low f-ratio telescope, such as an f/4 optical tube, only the best modern eyepieces will yield completely sharp images all the way out to the edge of the field of view. Some older designs may result in blurred views around the edge of the field of view, but the center will remain sharp. In telescopes with a relatively high f-ratio, such as an f/10 telescope, any well-made eyepiece will give a sharp image.
How Exit Pupil Relates to Power
The powers or magnifications at which a telescope will work well depend on the aperture of the instrument. In general, a larger telescope gathers more light and captures a broader wavefront, giving sharper images. One handy way to classify powers is in terms of "power per inch" of aperture. For example, 80x on an 8"-aperture telescope is 10 power per inch. Another way is to go by the size of the exit pupil. The term "exit pupil" describes the size of the bundle of light rays coming out of the eyepiece. Exit pupil size in inches is the reciprocal of power per inch. More commonly, exit pupil size is calculated in millimeters using these formulas:
Exit pupil size (mm) = Telescope aperture in mm ÷ Telescope magnification
Exit pupil size (mm) = Eyepiece focal length in mm ÷ Telescope f-ratio
The exit pupil must be smaller than the pupil of your eye, or else some of the light rays will not make it into the pupil, meaning the light will essentially be wasted. A young person's fully dark-adapted eyes may have 7mm-wide pupils. As you age, maximum pupil diameter decreases. For middle-aged adults, the practical maximum is closer to 5mm.
At the other end of the scale, at magnifications that yield an exit pupil in the range of 0.5mm to 1.0mm, empty magnification begins to set in, depending on the quality of your telescope and your eyes. In other words, this much magnification really starts to degrade the image you see. Here's a table of how various powers stack up:
Power Range | Exit Pupil Size | Power Per Inch | Power (3" Telescope) | Power (8" Telescope) | What It's Used For |
---|---|---|---|---|---|
Very Low | 4.0 - 7.0mm | 3 - 6x | 10 - 18x | 28 - 50x | Lowest usable power. Wide-field views of deep-sky objects under dark skies. |
Low | 2.0 - 4.0mm | 6 - 12x | 18 - 36x | 48 - 100x | General viewing; finding objects; most deep-sky observing. |
Medium | 1.0 - 2.0mm | 12 - 25x | 36 - 75x | 100 - 200x | Moon, planets, more compact deep-sky objects, wide double stars. |
High | 0.7 - 1.0mm | 25 - 35x | 75 - 100x | 200 - 280x | Moon and planets (in steady air), double stars, compact clusters. |
Very High | 0.5 - 0.7mm | 35 - 50x | 100 - 150x | 280 - 400x | Planets and close double stars in very steady air. |
What Does Parfocal Mean?
Eyepieces that are "parfocal" can be interchanged without the need for refocusing. This is desirable (but not necessary) when switching eyepieces while looking at the same object. Often, eyepieces of the same design, from a given manufacturer, will be parfocal. But the same eyepiece design from different manufacturers will likely not be parfocal. Some parfocal eyepieces may require a nominal amount of focus adjustment.
Illuminated-Reticle Eyepieces
These telescope eyepieces have etched crosshairs or other reticle grid patterns at the focal plane that can be illuminated so they're easily visible in the dark. An external illuminator arm incorporating a small red LED light, a button-cell watch battery or two, and a potentiometer for varying the brightness is screwed into the specially made eyepiece. An illuminated reticle eyepiece is needed for manual guiding exposures in astrophotography, and is useful for aligning a finder scope with the main telescope. It also comes in handy when drift-aligning an equatorial mount, or performing an alignment procedure for a computerized GoTo or IntelliScope system. Due to the presence of crosshairs in the field of view, illuminated reticle eyepieces aren't recommended for normal viewing through a telescope, although they can prove very useful for specific applications.
So, How Many Eyepieces Do I Really Need?
The short answer is a few. The long answer depends on your own goals. You can observe for a long time with one low-power and one high-power telescope eyepiece, although eventually you will want a few more focal lengths for more magnification options. Avoid the temptation to go all the way to the limits (very low and very high) until after you've filled in the middle range. For example, for an f/10 telescope, a 25mm and a 9mm eyepiece make a good starter set; you can add something around 15mm and perhaps 6mm next, and so on.
With a several different telescope eyepieces, you have a better chance of hitting the optimal power for the particular object you are observing, given the sky conditions at the time. Usually, you'll want to start out with low power (i.e., long eyepiece focal length, such as 25mm or 30mm) to get the object in the field of view of the telescope. Then you might try a slightly higher-power (shorter focal length, maybe 18mm or 15mm) eyepiece and see if the view looks any better. If it does, swap in an even higher-power eyepiece, etc., until you hit that "sweet spot" where image brightness, image scale, and the amount of visible detail combine to form the most pleasing view. Remember: higher power doesn't necessarily equal a better view.
To Zoom or not to Zoom?
Some telescope eyepieces provide a range of different focal length settings. Such "zoom" eyepieces can be very convenient if you don't like the idea of storing and carrying a number of separate eyepieces in order to use different magnifications. Many amateur astronomers enjoy using zoom eyepieces since they make it possible to increase or decrease power without swapping out eyepieces from the telescope focuser. In general, zoom eyepieces do not perform quite as admirably as single focal length eyepieces, due to the fact they are typically made with more optical elements, which can reduce overall image brightness and clarity. However, many amateur astronomers consider the increased versatility and convenience of a zoom eyepiece to be preferable to an assortment of single focal length eyepieces. Many high-end premium zoom eyepieces are designed to optimize performance, but they can be a bit pricier than other zoom eyepieces.
Using a Barlow Lens with Eyepieces
You can also use a 2x Barlow lens to boost the power (or reduce the effective focal length) of any eyepiece by a factor of two. Thus, instead of a 3mm eyepiece, you can use a 6mm eyepiece with a 2x Barlow lens and get the same magnification. Using a Barlow is easy: just insert an eyepiece into the Barlow lens, then insert the Barlow/eyepiece combination into the telescope focuser and adjust until the image is sharp. By using a Barlow lens you can get away with having fewer eyepieces in your collection, while still having a variety of magnifications at your disposal. To gain the maximum benefit from the Barlow lens, choose eyepiece focal lengths that are not multiples of each other. In other words, if you have eyepieces of 25mm, 12.5mm, and 6mm - multiples of 2 - then a 2x Barlow won't provide much in the way of additional magnifications. But if your eyepieces are 25mm, 15mm, and 10mm, then use of the 2x Barlow with each, respectively, will provide 12.5mm, 7.5mm, and 5mm effective focal lengths - just like having three additional (and different!) eyepieces. Since Barlow lenses add glass elements into the light path, you may notice a slight dimming of the image when alternating from an eyepiece to a Barlow and eyepiece combination. Barlow lenses are also available in 3x and 5x models for those looking to significantly increase power.
Closing Thoughts
Using different eyepieces can profoundly increase the versatility and functionality of any telescope. While shopping for eyepieces, remember these basic tips:
Keep in mind the specifications described above and you're sure to choose an ocular that will provide you with night after night of enjoyment with your telescope(s). And remember, Orion is here to help with any questions you have along the way. Just send us an email at sales@telescope.com, contact us via live chat, or and we'll help you find the right telescope eyepieces.
Clear skies!
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What do you do on a sunny day? Chances are you slip a pair of polarized sunglasses over your eyes. They cut down glare and appear to make colors, such as a cobalt-blue sky, look snappier.
Backyard astronomers do the same thing when they thread eyepiece filters into a telescope eyepiece to, say, cut the Moon's glare or bring out cloud bands on Jupiter. Eyepiece and telescope filters improve the view. And in the case of solar observing, they actually provide a safe way to look at the Sun directly.
Solar Filters
Solar filters come in two main varieties: metal-coated black-polymer film and glass. In both instances, it's a metal alloy electrostatically applied to a surface that filters out the Sun's blinding intensity and harmful infrared radiation. Glass solar filters typically slip over a telescope's front aperture to block the light before it enters the scope. Film solar filters can be found in rolls or sheets of material that is wrapped around the front of a telescope, and more deluxe versions can have a plastic filter cell specially fitted for the front aperture of the telescope.
By some measures, glass solar filters offer greater durability than foil-like black-polymer film. On the other hand, black polymer can take an occasional drop on the ground without worry of cracking or shattering, like glass. The type of metal coating applied to black polymer film makes the Sun appear blue or neutral-white, while the coating on glass solar filters yields a more realistic yellow image.
Solar filters designed to fit a telescope eyepiece should be avoided. They are extremely dangerous because they sit right where the sunlight is most concentrated (focused). Remember burning dried leaves with a magnifying glass when you were a kid? Well, likewise, the heat that builds up at the eyepiece will eventually cause the filter to crack, which can permanently damage your eyes. If you come across a filter like this, get rid of it. See our handy solar filter reference chart to find the right solar filter for your telescope or pair of binoculars.
Moon Filters
Believe it or not, you're also dealing with bright, albeit reflected, sunlight when you turn your scope on the Moon. A noncrescent Moon will consistently leave spots even in a hardened lunar observer's eyes, although this will not damage your eyes.
To tone down the glare, a Moon filter can be used. This inexpensive accessory threads into a telescope eyepiece and blocks a large percentage (typically over 80%) of the light, making for more comfortable viewing and bringing out more lunar surface details.
A variable-polarizing Moon filter is a little fancier, allowing you to "dial in" the amount of light reduction you want. In so doing, it acts as something of a dimmer switch for your telescope. Such variable-polarizing filters actually consist of two polarized filters mounted in a rotating housing, which you turn to adjust the brightness. Double star observers often use variable polarizers to distinguish, or enhance, tightly paired targets that sometimes smear together in each other's light.
Planetary (Color) Filters
Backyard observers also utilize an array of color eyepiece filters to glean subtle features on the planets. Earth's atmosphere is in constant fluctuation; turbulent air currents blur fine surface detail on solar system objects, like planets, viewed through a telescope. Faint, contrasting areas blend together due to irradiation - distortion of the boundaries between light and dark areas. Using color eyepiece filters can help reduce such distortion.
A color filter zeros in on a narrow region of the spectrum, reducing the scattering of interfering wavelengths. Because many planets have a characteristic color (e.g., Mars is reddish), a filter can dramatically increase detail by reducing the predominant hues and uncovering hidden contrast and surface markings. That's why the Red Planet is most effectively enhanced with a green filter. Each color eyepiece filter passes its characteristic color of light while blocking complementary colors. For example, green objects will appear bright (pale) through a green filter, and dark through a blue or red filter. Red features will appear bright through a red eyepiece filter and dark through a green or blue eyepiece filter.
Telescope eyepiece filters thread into the barrel of an eyepiece. Usually the aluminum cell holding the filter is threaded such that two or more can be "stacked," to achieve simultaneous filtering of more than one color.
Color filters go by their "Wratten" numbers. Here is a rundown of the color eyepiece filters that are useful for enhancing detail on each planet and some other objects.
Mercury
#25 Red will make the planet's disk stand out against a blue sky, permitting daytime or twilight viewing. Mercury is usually best observed just after sunset, when the sky is awash in orange light, so employ #21 Orange with high magnifications to see the planet's phases.
Venus
No matter what telescope aperture you use, Venus's excessive brightness usually causes a very "overexposed," roiling image. With a #47 Violet filter, or stacked #58 Green and #80A Medium Blue filters, you'll reduce the severe twinkling for a better view of the fascinating changing phases.
Mars
#25 Red passes the predominant reflections of surface plains and maria, and #21 Orange is good for reducing the intense glare to enhance detail and mottling. The polar caps stand out with #15 Deep Yellow and #80A Medium Blue; examine the melt lines with #58 Green.
Jupiter
This great planet reveals its cloud bands, loops, festoons, ovals, and Red Spot with #80A, #58, and #21. Go from seeing only two bands without a filter to seven or more with a filter! Try stacking filters to reduce the heavy glare.
Saturn
Many subtle details are improved by #15 Deep Yellow. See the difference in brightness of the extremes of the rings with #25, #58, or #80A. The #15 filter also helps sharpen Saturn's image in photographs, improving the resolution of the Cassini division.
Moon
Reduce the Moon's glare with #80A Medium Blue, and enhance the contrast of lunar rilles and strata with #15 Deep Yellow.
Other Uses
You will improve black-and-white photographs by blocking UV light with #15 Deep Yellow filter. Refractor chromatic distortion is also reduced by #15, and by #80A filters. The #82A Pale Blue filter is great for stacking with other colors, and can adjust film color balance by absorbing excess yellow and red. #58 Green will block street light while passing much of the wavelength of doubly ionized oxygen in emission nebulas. Try #25 Red for long black-and-white exposures of the Omega or Rosette Nebulas.
Deep-Sky Filters
One very useful weapon in the fight against light pollution is a light-pollution filter. So-called broadband filters, like the Orion SkyGlow, effectively block the wavelengths of light generated by incandescent, sodium, and mercury-vapor lights, which brighten the evening skies in cities and suburbs, while letting through the desirable wavelengths emitted by galaxies and emission nebulas (hydrogen alpha, hydrogen beta, and oxygen III). This type of eyepiece filter is also popularly called a light-pollution-reduction, or LPR, filter. Bright, light-polluted skies appear much darker, and the contrast between object and sky is improved significantly.
Narrowband eyepiece filters, such as the Orion UltraBlock, allow an even narrower range of wavelengths through. This type of eyepiece filter is often called a "nebular filter" because it is particularly effective in enhancing detail and contrast of emission and planetary nebulas. Galaxies and reflection nebulas don't benefit much.
Narrowband eyepiece filters block all forms of light pollution, including wavelengths from incandescent and fluorescent lighting, which broadband filters cannot stop. So they are effective in areas with severe light pollution. They will transform a poor, milky-sky urban backyard into something useable for deep-sky observing.
Still, their effect is most dramatic under a truly dark sky.
Other deep-sky eyepiece filters are "tuned" with bandpasses intended for the light of specific targets. Oxygen III, or O-III, filters are optimized for planetary nebulae. H-beta eyepiece filters convey the blue-green luminescence of faint emission nebulae like the Horsehead or California Nebulas. And comet filters permit the passage of light given off by, of all things, glowing cyanogen gas that surrounds comets.
So, thanks to a whole battery of eyepiece and telescope filters we can see things that run the gamut from sunspots to the shattered remains of an exploded star. If you enjoy even a moderate amount of observing, you will benefit by having a few filters at your disposal. Chances are, you will reach for an eyepiece filter at night as often as you reach for sunglasses on a sunny day.
They almost always improve the view!
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One of the more useful and cost-effective tools in an amateur astronomer's accessory case is a Barlow lens. Invented in the early 1800s by British mathematics professor Peter Barlow, it is a simple concave (negative) lens that, when placed between a telescope's objective lens or mirror and the telescope eyepiece, amplifies the magnifying power of the instrument.
If the standard eyepiece in your telescope yields a magnification of 50x, a 2x Barlow will boost that to 100x (50 x 2). If a high-power eyepieces in your scope yields 150x, insertion of a 2x Barlow lens before the eyepiece will boost that to 300x (150 x 2).
A Barlow lens works by reducing the convergence of the light cone heading toward the telescope eyepiece. In this way it essentially increases the focal length of the telescope. Since magnification is determined by dividing the telescope's focal length by the eyepiece's focal length, you can see that by doubling the telescope's focal length, a Barlow lens doubles the magnification of the system for a given telescope eyepiece.
A Barlow lens is useful in several ways. First, it allows you to reach a higher maximum power. This is not always very beneficial, however, because the maximum useful power is generally limited not by the telescope or eyepiece but by prevailing atmospheric conditions ("seeing"). If atmospheric turbulence renders the image wavy and fuzzy at 150x, doubling the power to 300x is not going to help; it'll only degrade the image even more.
Barlows are particularly useful with telescopes that have short focal lengths. Such scopes often do not reach high powers even with fairly short focal-length telescope eyepieces. A Barlow lens can increase the magnification and allow the short focal length telescope to achieve its maximum useable power.
Perhaps the biggest benefit of a Barlow is that it doubles the number of magnifications available to you, effectively doubling the number of telescope eyepieces in your repertoire. If you have 26mm, 18mm, and 10mm eyepieces, for instance, adding a 2x Barlow will allow them to function as 13mm, 9mm, and 5mm eyepieces ? it's like getting three more eyepieces for the price of one Barlow lens (which often costs less than one telescope eyepiece)!
A less obvious but very nice perk of Barlow lenses is that they can make high-power viewing through a telescope more comfortable. High-power (short-focal-length) eyepieces often have very little eye relief, which requires that you position your eye very close to the lens to see the image comfortably. But a Barlow lens allows you to achieve the same magnification with a lower-power eyepiece, which typically has more eye relief. This can be a real benefit for eyeglass wearers, enabling them to see the whole field of view at higher powers, when normally they cannot. Also, many high-power telescope eyepieces feature very small eye lenses, which can be difficult to look into. Using a Barlow lens with a longer focal length telescope eyepiece allows you to enjoy the same magnification, but with a larger and more comfortable eye lens to peer into.
A 2x Barlow lens will actually provide 3x magnification when placed in front of the telescope diagonal on refractor, Schmidt-Cassegrain and Maksutov-Cassegrain telescopes.
Lastly, a precision-made Barlow with antireflection coatings can actually improve eyepiece performance, providing sharper images and reducing edge-of-field optical aberrations at the expense of only a two or three percent reduction in image brightness. In fact, many deluxe high-power eyepieces contain built-in Barlow lens elements to achieve their high magnifications.
Choices in Barlow Lenses
When selecting a Barlow lens, the first thing you need to determine is the barrel size of the telescope eyepieces you intend to use with it. (The barrel size is the diameter of the eyepiece tube that drops into the focuser. The most common eyepiece barrel size is 1.25"; some larger telescopes and some refractors can also use 2" eyepieces, and some inexpensive telescopes still use smaller 0.965" eyepieces.) Whatever the barrel size of your telescope eyepieces, you'll want to select a Barlow of the same diameter.
Barlows also come in different magnifications. The most common Barlow magnification is 2x, which means that it doubles the power of any eyepiece with which it's used. There are also 3x and 5x Barlows available, and even some in-between magnifications such as 1.5x and 2.5x.
A 2x Barlow lens provides 2x magnification when placed between the telescope diagonal and eyepiece.
Make sure you get a quality Barlow lens that is fully antireflection coated or fully multi-coated. Most cheap Barlows included with low-end department-store telescopes are virtually worthless due to their lack of antireflection coating and resulting poor performance.
Using a Barlow Lens
A Barlow is very simple to use: It is inserted in place of the telescope eyepiece in the focuser, and the eyepiece is then inserted into the Barlow itself. When the Barlow is inserted into the optical path you will need to refocus, and often the change of focus required is quite large. To avoid excessive refocusing, therefore, you may find it easiest to sequence through your eyepieces without the Barlow, then, if the object and conditions warrant higher power, insert the Barlow and run through your eyepieces again starting with the longest focal-length (lowest power) eyepiece. As with all visual observing, don't increase magnification to the point that the image becomes fuzzy. Once the image becomes fuzzy there is no more detail to be seen, and such empty magnification makes it more difficult to discern detail in celestial sights.
Use of a Barlow should be factored into your choice of telescope eyepieces. If you're just starting out, you'll find that most telescopes come with a single low-power eyepiece, often of about 25mm focal length or thereabouts. A good strategy is to purchase a 2x Barlow and a second eyepiece of about 1/3 the focal length of your first telescope eyepieces. (For example: if your first eyepiece is a 25mm eyepiece, your second eyepiece would therefore be in the range of 8mm to 10mm). Those two telescope eyepieces and a single 2x Barlow lens will give you a range of four different magnifications, from low power to relatively high power ? a very good way to get started!
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Orion offers telescopes for every level: Beginner, Intermediate, Advanced, and Expert. From our entry level beginner telescopes for amateur astronomers to our Dobsonian telescopes to our most advanced Cassegrain telescopes and accessories, you can find the best telescope for you. Because we sell direct, we can offer you tremendous value at a great price. Not sure how to choose a telescope? Orion's Telescope Buyer's Guide is a great place to start.
Orion binoculars are known for quality optics at a great price. We offer binoculars for every viewing interest, including astronomical binoculars, compact binoculars, waterproof binoculars, birding binoculars, and sport and hunting binoculars.
Orion's telescope and astrophotography accessories will enhance your telescope enjoyment without breaking the bank. Expand your viewing experience with accessories ranging from moon filters to power-boosting Barlow lenses to advanced computerized telescope mounts. Capture breathtaking photos with our affordable astrophotography cameras. And when you're stargazing, Orion's telescope cases and covers, observing gear, red LED flashlights, astronomy books and star charts will make your observing sessions more convenient, comfortable and meaningful.
At Orion, we are committed to sharing our knowledge and passion for astronomy and astrophotography with the amateur astronomy community. Visit the Orion Community Center for in-depth information on telescopes, binoculars, and astrophotography. You can find astrophotography "how to" tips and share your best astronomy pictures here. Submit astronomy articles, events, & reviews, and even become a featured Orion customer!