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Barlow Lenses, Coma Correctors, and Focal Extenders

|||Barlow Lenses, Coma Correctors, and Focal Extenders

Increase the magnification of your eyepiece without spending a fortune. Multiple magnification Barlow lenses can be used alone or in doubles. All have coma correction for coma free viewing of objects as they drift across the field of view.

  • APM 1.25 Inch Coma Corrector ED 2.7x Barlow Element is a photo-visual apochromatic Barlow with real ED glass, designed by Gerd Düring in Germany.
  • APM 1.25 Inch Coma Corrector ED 2.7x Barlow Lens is a photo-visual apochromatic Barlow with real ED glass, designed by Gerd Düring in Germany.
  • APM 1.25 Inch Coma Corrector ED 6.25x Double Barlow Lens is a unique photo-visual apochromatic 2.7x Barlow with real ED glass that be combined with a second APM 2.7x Barlow to increase the magnification factor to 6.25x.
  • APM 2 Inch Barlow Lens is well made both in design and craftsmanship, both lenses are fully multi-coated for the best possible contrast and transmission.
  • APM 2 Inch Coma Corrector Telecentric 1.5x Barlow Lens was designed by well known physicist and optical designer Philipp Keller. The telecentric design prevents the need for distance to be individually adjusted for each eyepiece.
  • A good Focal Extender adds some real versatility to your telescope accessory line-up. First of all, it allows you to increase the magnification of any eyepiece with the same barrel size that you already own. In other words, 3 eyepieces offer 6 magnification choices with the addition of a focal extender. Secondly, most of the time, lower magnification eyepieces have better eye relief than higher power models. When using a focal extender to increase your magnification, you get to enjoy the generous eye relief of the lower power eyepiece, and that's quite a bonus, especially for eyeglass wearers or for those with fast telescopes who can really push high magnification eyepieces. Remember, we make focal extenders in 2X, 3X and 5x models, so there is something for every style of telescope.
  • The Explore Scientific 2X Focal Extender (2.0-inch O.D.), accepts both 1.25-inch O.D. and 2.0-inch O.D. format eyepieces and camera adapters. Fully EMD-Coated on all air-to-air lens surfaces, with all lens elements edge-blackened to produce superior contrast, this focal extender adds some real versatility to your telescope accessory line-up. First of all, it allows you to increase the magnification of any eyepiece with the same barrel size that you already own. In other words, 3 eyepieces offer 6 magnification choices with the addition of a focal extender. Secondly, most of the time, lower magnification eyepieces such as the 30mm 82 Degree Series Waterproof Eyepiece have better eye relief than higher power models. When using a focal extender to increase your magnification, you get to enjoy the generous eye relief of the lower power eyepiece, and that's quite a bonus, especially for eyeglass wearers or for those with fast telescopes who can really push high magnification eyepieces. Remember, we also make 1.25-inch O.D. Focal Extenders in 2X, 3X and 5x models, so there is something for every style of telescope.
  • A good Focal Extender adds some real versatility to your telescope accessory line-up. First of all, it allows you to increase the magnification of any eyepiece with the same barrel size that you already own. In other words, 3 eyepieces offer 6 magnification choices with the addition of a focal extender. Secondly, most of the time, lower magnification eyepieces have better eye relief than higher power models. When using a focal extender to increase your magnification, you get to enjoy the generous eye relief of the lower power eyepiece, and that's quite a bonus, especially for eyeglass wearers or for those with fast telescopes who can really push high magnification eyepieces. Remember, we make focal extenders in 2X, 3X and 5x models, so there is something for every style of telescope.
  • The Explore Scientific 3X Focal Extender (2.0-inch O.D.), accepts both 1.25-inch O.D. and 2.0-inch O.D. format eyepieces and camera adapters. Fully EMD-Coated on all air-to-air lens surfaces, with all lens elements edge-blackened to produce superior contrast, this focal extender adds some real versatility to your telescope accessory line-up. First of all, it allows you to increase the magnification of any eyepiece with the same barrel size that you already own. In other words, 3 eyepieces offer 6 magnification choices with the addition of a focal extender. Secondly, most of the time, lower magnification eyepieces such as the 30mm 82 Degree Series Waterproof Eyepiece have better eye relief than higher power models. When using a focal extender to increase your magnification, you get to enjoy the generous eye relief of the lower power eyepiece, and that's quite a bonus, especially for eyeglass wearers or for those with fast telescopes who can really push high magnification eyepieces. Remember, we also make 1.25-inch O.D. Focal Extenders in 2X, 3X and 5x models, so there is something for every style of telescope.
  • A good Focal Extender adds some real versatility to your telescope accessory line-up. First of all, it allows you to increase the magnification of any eyepiece with the same barrel size that you already own. In other words, 3 eyepieces offer 6 magnification choices with the addition of a focal extender. Secondly, most of the time, lower magnification eyepieces have better eye relief than higher power models. When using a focal extender to increase your magnification, you get to enjoy the generous eye relief of the lower power eyepiece, and that's quite a bonus, especially for eyeglass wearers or for those with fast telescopes who can really push high magnification eyepieces. Remember, we make focal extenders in 2X, 3X and 5x models, so there is something for every style of telescope.
  • After hours at the eyepiece, you finally get to view the fruits of your astrophotography labors. The stars in the center of the field pop like brilliant precise points of light. But as you survey the image, you notice the stars at the edge have taken on an unnatural comet-like shape. Your long night has been marred by coma. Coma is a common plague of the Newtonian reflector design, and its annoying presence at the outskirts of an image can be a bane for astronomers of all levels. Explore Scientific’s HR Variable Coma Corrector is a high-performance optical corrector designed by world famous optical designer Harrie Rutten, and it will help you minimize or even eliminate image aberrations caused by this off-axis optical phenomenon even in fast Newtonians. This 2-inch coma corrector with is EMC Coated to reduce internal reflections and its spacer with markings allow you to use the device on almost any Newtonian telescope with a parabolic primary mirror, even fast Newtonians such as the BRESSER N20839 f/3.9 Photo Newtonian. Tightly secured by three thumbscrews, this accessory comes with two adapters (.75” and 1”) to secure to your T adapter and a protective cap.

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