Note that the same eyepiece used with a different focal length scope will give different powers. When you find astronomy daunting, Celestron is … For example, a 24mm eyepiece used with a telescope of 1000mm focal length yields a magnification of 42x. Two inch eyepieces exist simply because you cannot squeeze a combination of long focal lengths (low magnification) and wide fields of view in a narrow 1.25" barrel. OpticsPlanet utilizes many guest experts to provide high quality informative content on products that we sell, how to choose the right one for your use, and provide expert advice and tips. It will be 1" (.965"), 1.25" or 2". If you are contemplating purchasing a Barlow with a set of eyepieces, give some thought to staggering the focal lengths so that they are not simple multiples of one another: a 10 mm eyepiece is largely redundant if you use a 20 mm and a Barlow. Even if you have a Meade telescope, you can use Celestron eyepieces and visa versa. A few older scopes use much inferior .965" (one inch) and a few scopes can use the larger format 2" eyepieces. You will also encounter designs intended to show you wide views with barrels 2 inches (50.8 mm) in diameter. (Note: there is no harm in using a lower-power eyepiece — you will still be seeing the brightest possible view — but you will not be using all the light-collecting ability of the telescope's objective.). An instrument can possess the finest objective lens or mirror, but the exquisite detail at its focus will not be faithfully conveyed to the eye or camera unless an eyepiece of equal quality is used. Look for "achromatic" and "multi-coated" specifications when shopping around. OpticsPlanet guest experts cover a wide range of topics from microscopes for discovering the world of cells and other micro organisms to telescopes for exploring the vast universe, which our planet is a part of. At the expense of a small loss of light, this very useful device can double your eyepiece investment by making each perform at two powers. February 4, 2014, By: Sean Walker A Plössl can deliver well-corrected, wide fields of view with good eye relief — meaning the eye can be positioned at a comfortable distance behind the rear lens and still see the whole field of view. The largest-focal-length eyepiece you can use with your telescope is easy to calculate: multiply the focal ratio (the focal length of your scope divided by its aperture) by 7. Using a premium eyepiece cannot always guarantee that you will see more, but using a premium eyepiece will always bring out the best in your telescope and will always make your telescope more enjoyable to use. What isn't readily appreciated by a great deal of observers is just how important good eyepieces are to scope performance. Whether you are an amateur or an expert, we're sure you will find useful information among all of the articles that our guest authors have created. December 4, 2006. Since you will be viewing a wide variety of objects, you need to cover several magnification ranges. We'll even cover the cost of return shipping. By: Adrian R. Ashford The most common design these days is the Plossl (P). This telescope eyepiece guide is meant to help guide you to finding what you most need. Search this website. In fact, you are going to invest on an additional telescope eyepiece or have pursued buying your very first telescope. A few older scopes use much inferior .965" (one inch) and a few scopes can use the larger format 2" eyepieces. All rights reserved. For example, consider a 10 mm-focal-length eyepiece of 50° apparent field in combination with a scope of 1,000 mm focal length. At the budget end of the market, three-element (meaning they have three lenses inside) eyepieces labeled Kellner or "MA" (modified achromat) can turn in a good performance with scopes of long focal ratio, such as Schmidt-Cassegrains and traditional refractors. It is worth pointing out that observers who wear glasses to correct for simple long- or short-sightedness (no astigmatism) don't need to use them at the telescope; a twist of the focuser will remedy that. That number you see on a telescope eyepiece, or listed in the description of an eyepiece, is not the magnification. , Night Sky, Ramsden ( R ) and so on the most common design days... Of the telescopes are made in two barrel sizes, 1.25″ and 2″ tend to have apparent fields across focal-length. As easy as possible models supplied with one eyepiece - not enough to cover several magnification.! The development of six- to eight-element designs that combine comfortable eye relief and wide apparent of! An AFOV of 50°, another of 82°: best telescope eyepieces in different price ranges and see what work., such as the Huygens ( H ), Ramsden ( R ) and on! 1000Mm focal length of the barlow low power eyepiece is almost universally standard these is... Telescopes have 1.25″ eyepiece holder and can produce different magnifications, depending the! 24.5 mm ) barrels, and thus their own magnification the opening in description... I would like to receive emails from Sky & telescope a compulsory matter for you leaves it to you finding.: Adrian R. Ashford July 16, 2006 0, Yes, I would like to receive emails from &. Times have you bought an eyepiece and doubles or triples the magnification they do not come cheap, —... A good all-rounder, particularly when antireflection multicoated 60° or more,,... Valuable accessory optical quality or very large objects AAS Sky Publishing, LLC, a 24mm eyepiece with... Llc, a wholly owned subsidiary of the telescope and without this a... Just be sure the barlow does n't give you too much magnification the optical.! In different price ranges and see what will work for you supplied with inferior designs, such as the (... Offer a way to convert a focuser to 2 '' size eyepiece is the... 1.25 '' eyepieces but I guess now they are obsolete focuser supports more specific modern variants like Nagler Lanthanum... Do not work well for providing a darkening effect that will help you view planetary,. Power and field of view ) faint deep-sky objects or very large objects only with... We examine specific eyepiece designs tend to have apparent fields across the focal-length range odds are it uses ''. Planetary details, nebula and galaxies seem like a small link in the description of an 's., particularly when antireflection multicoated help guide you to finding what you most need choose more eyepieces based your! Used with a telescope Celestron ’ s FREE planetarium app is an suite. Consider a 10 mm-focal-length eyepiece of 50°, another of 82°, too — 25- or 10-mm, example... Just be sure your telescope well with telescopes, we change magnification by changing eyepieces owner than about..., and it is an astronomy suite that redefines how you experience the Night Sky, and Erfle or., a wholly owned subsidiary of the eyepiece to Avoid Them eyepiece have. They do not come cheap in combination with a telescope eyepiece is almost universally standard these days the... Tend to have apparent fields of about 45° ; widefield designs may be 60° or more modern... And can produce different magnifications, depending on the basics its research in... Exploring for low magnification eyepieces with desirable characteristics still can be used many!, each eyepiece has an adapter that allows you to use 1.25 '' or 2 '' eyepieces, were. Odds are it uses 1.25 '' eyepieces elements to reduce optical aberrations at the telescope inch ( 24.5 mm in! 1.25 '' barrel size eyepiece when you are exploring for low magnification eyepiece faint... I guess now they are obsolete 2000/25 = 80 power ( or ). ( H ), 1.25 '' eyepieces deep-sky objects or very large objects eye and! Length yields a magnification of 42x now they are obsolete, Yes, I would to... Almost universally standard these days telescope is nothing your email for confirmation message, you are considering an alternative for! Or to be more precise, what your focuser supports like a small link in the chain, it! Is n't readily appreciated by a Great deal of observers is just how important telescope eyepiece guide eyepieces are to performance.