Telescope Accessories

|Telescope Accessories
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    2nd Quality Filters have minor imperfections that do not significantly affect performance. Lumicon 1.25 Inch Single Polarizing Filter is the best all-purpose lunar and planetary filter, reducing glare and increasing contrast on the Moon and planets. In addition to polarizing light, it can also reduce its intensity by a factor of about 3.
  • This Red Continuum filter (645 nm, 5 nm FWHM) produces a star map without the H-a or SII emission in order to subtract stars from emission images. Astrodon NB filters are renowned for not producing halos around stars and not leaking NIR light. https://youtu.be/t5NAIbV1l8o  
  • 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.
  • Safely attach telescope optical tubes and accessories with APM 120mm Deluxe Dovetail Rail. Features US 1/4-20 inch size telescope connecting screws.
  • Safely attach telescope optical tubes and accessories with APM 150mm Deluxe Dovetail Rail. Features US 1/4-20 inch size telescope connecting screws.
  • APM 15mm Ultra Flat Field Eyepiece delivers high quality in a very compact design and features over-sized lenses for a large 65° field of view with a 16mm eye relief.
  • APM 18mm Ultra Flat Field Eyepiece delivers high quality in a very compact design and features over-sized lenses for a large 65° field of view with a 20mm eye relief.
  • 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.
  • APM 2 Inch Diagonal Mirror is a high-quality mirror with dielectric coating, 99% Reflection Coating, and a 2" to 1.25" Deluxe Eyepiece Adapter with centering clamping via brass ring and T2 thread.
  • Safely attach telescope optical tubes and accessories with APM 300mm Deluxe Dovetail Rail. Features US 1/4-20 inch size telescope connecting screws.
  • APM 50mm Straight Through Finder Scope is a high quality 50mm finder scope offering a universal base with a wide contact surface.  The quick clamp bracket allows for fast removal and re-installation of the finder scope.
  • APM 60mm 90 Degree Erect Image Finder Scope is a high quality 60mm finder scope offering a universal base with a wide contact surface.  The 90° erect image prism provides an upright and correct image while offering multi-coated sharp, bright optics.
  • APM M63 Riccardi Adjustment Flange is an additional flange to eliminate tilting on our APM M63 Riccardi APO-Reducer. Maximizes sharpness too!
  • APM M82 Riccardi Adjustment Flange is an additional flange to eliminate tilting on our APM M82 Riccardi APO-Reducer. Maximizes sharpness too!
  • H-α (hydrogen-alpha) at 656 nm (nanometers) is deep red in color and the most popular narrowband filter, and this 20nm H-α is the same formulation but in a wider bandpass. Hydrogen is ubiquitous in the cosmos and is present in emission nebula (North American, Pelican), planetary nebula (Dumbbell, Ring), Wolf-Rayet objects (Crescent, Thor’s Helmet) and supernova remnants (Veil). Many imagers like to present just a black-and-white H-α image of an object. It is has a beauty all by itself, like an Ansel Adams photo.   https://youtu.be/t5NAIbV1l8o  
  • H-α (hydrogen-alpha) at 656 nm (nanometers) is deep red in color and the most popular narrowband filter. Hydrogen is ubiquitous in the cosmos and is present in emission nebula (North American, Pelican), planetary nebula (Dumbbell, Ring), Wolf-Rayet objects (Crescent, Thor’s Helmet) and supernova remnants (Veil). Many imagers like to present just a black-and-white H-α image of an object. It is has a beauty all by itself, like an Ansel Adams photo. However, most imagers blend their H-α data into their red RGB data to enhance structural detail while maintaining a “natural” look. Therefore, the H-α filter should be your first narrowband addition to your LRGB filters. The basic imaging set of 5 filters becomes LRGBH-α. Astrodon H-α filters have a center bandwidth of 656.3 nm https://youtu.be/t5NAIbV1l8o  
  • NII Filter, 3nm, center bandwidth 658.4 nm What about NII and H-a? This is a bit complicated. It is not well known that most H-a filters pass both H-a and NII. H-a emits at 656.3 nm and NII emits most strongly at 658.4 nm (and weakly at 653.8 nm). These are very close together spectrally. Thus, most H-a filters are wide enough (e.g. 4.5 nm bandwidth and wider) to pass both emission lines as shown for the older Astrodon 6 nm filter above. Our 3 nm H-a begins to separate both emission lines and reduces the NII contribution significantly. In this example the 3nm filter only transmits 15% at the NII 658.4 nm wavelength, whereas the H-a remains unchanged. As mentioned earlier, some objects are enriched in NII, such as planetary nebula and Wolf-Rayet bubbles. The Dumbbell Nebula, M27, is a good example. The wispy clouds in the core of M27 are dominantly NII. A tricolor narrowband image is also shown below, mapping OIII to blue, H-a to green and NII to red to produce a beautiful color image. This information provides you with a choice based upon your light pollution, desire for more detail, or simply wanting all the photons you can get out of your H-a filter. Our NII filters have a center bandwidth of 658.4 nm. https://youtu.be/t5NAIbV1l8o  
  • The next filter to complement your LRGBH-a set is an oxygen filter. OIII (“ohthree”) emits light near 500 nm and is a blue-green- or teal-colored filter. Many of my images of planetary nebula and supernova remnants are taken only with H-a and OIII filters. They show great structural detail, but have natural colors, looking like an RGB image. Astrodon OIII filters have a center bandwidth of 500.1 nm. https://www.youtube.com/embed/t5NAIbV1l8o
  • If you want the look of Hubble Space Telescope (HST) images, such as the famous “Pillars of Creation” (the Eagle Nebula, Messier 16), then the next filter to consider adding to your collection after H-a and OIII is the SII (es-two) or sulfur filter. The SII filter, like H-a, is a deep red filter near 672 nm. H-a, OIII and SII filters provide that Hubble look for many emission nebula. Again, tri-color narrowband imaging with these three filters can be done with the moon up, so your equipment is not sitting dormant for several weeks. Astrodon SII filters have a center bandwidth of 671.6nm https://youtu.be/t5NAIbV1l8o  
  • H-α (hydrogen-alpha) at 656 nm (nanometers) is deep red in color and the most popular narrowband filter. Hydrogen is ubiquitous in the cosmos and is present in emission nebula (North American, Pelican), planetary nebula (Dumbbell, Ring), Wolf-Rayet objects (Crescent, Thor’s Helmet) and supernova remnants (Veil). Many imagers like to present just a black-and-white H-α image of an object. It is has a beauty all by itself, like an Ansel Adams photo. However, most imagers blend their H-a data into their red RGB data to enhance structural detail while maintaining a “natural” look. Therefore, the H-α filter should be your first narrowband addition to your LRGB filters. The basic imaging set of 5 filters becomes LRGBH-α. Astrodon H-α filters have a center bandwidth of 656.3 nm https://youtu.be/t5NAIbV1l8o  
  • Bring Out The Faint Structures In Nebulae Astrodon Narrowband filters set a new bar of performance and durability for imaging and research. We offer 5 nm and ultra-narrow 3 nm bandwidths. Astrodon OIII filters have a center bandwidth of 500.1 nm. https://youtu.be/t5NAIbV1l8o  
  • If you want the look of Hubble Space Telescope (HST) images, such as the famous “Pillars of Creation” (the Eagle Nebula, Messier 16), then the next filter to consider adding to your collection after H-a and OIII is the SII (es-two) or sulfur filter. The SII filter, like H-a, is a deep red filter near 672 nm. H-a, OIII and SII filters provide that Hubble look for many emission nebula. Again, tri-color narrowband imaging with these three filters can be done with the moon up, so your equipment is not sitting dormant for several weeks. Astrodon SII filters have a center bandwidth of 671.6nm   https://youtu.be/t5NAIbV1l8o  
  • For placing Astrodon 50 mm diameter filters in 52 mm threaded mounts for camera lenses. https://youtu.be/t5NAIbV1l8o  
  • Astrodon Clear Filters

    $173.00$499.00
    UV-Blocked Clear filters with 395 nm cut-on (50% transmission at 395 nm) and at least 97% transmission to 1000 nm. Often purchased with our photometric filters. https://youtu.be/t5NAIbV1l8o  
  • Astrodon introduced the ExoPlanet-BB filter for use in amateur-scale telescopes to measure light curves of exoplanets. https://youtu.be/t5NAIbV1l8o  
  • This filter isolates only the hydrogen-beta line of the spectrum (486nm) in a 15nm wide bandpass. https://youtu.be/t5NAIbV1l8o  
  • SIMPLIFY YOUR IMAGING! Astrodon LRGB Gen2 E-Series Tru-Balance Filter Sets were designed for cameras containing the full-frame KAF8300, KAF3200, KAF6303, KAF16200, KAF16803 sensors, as well as most Sony and back-thinned sensors and other cameras with Progressive Scan, Front Illuminated or Back Illuminated Sensors. https://youtu.be/t5NAIbV1l8o  
  • SIMPLIFY YOUR IMAGING! The E-Series filters were designed for cameras containing the full-frame KAF8300, KAF3200, KAF6303, KAF16803 sensors. They are also a good choice for the latest Sony and back-thinned sensor or any Progressive Scan Sensor, Front Illuminated or Back Illuminated. https://youtu.be/t5NAIbV1l8o  
  • SIMPLIFY YOUR IMAGING! Astrodon LRGB Gen2 I-Series Tru-Balance Filter Sets were designed for cameras containing the Interline KAI11002, KAI16000, sensors or other cameras with Interline Transfer Sensors. https://youtu.be/t5NAIbV1l8o  
  • SIMPLIFY YOUR IMAGING! Astrodon LRGB Gen2 I-Series Tru-Balance Filter Sets were designed for cameras containing Interline Transfer sensors. https://youtu.be/t5NAIbV1l8o  
  • UV/NIR-blocked filter used for both E- and I-Series LRGB sets. Transmits at least 97% between 400 and 700 nm. 395 nm cut-on (50% transmission at 395 nm); blocked above 705nm. https://youtu.be/t5NAIbV1l8o  
  • GUIDE YOUR TELESCOPE IN FRONT OF YOUR FILTERS NEW DESIGN!! ACCOMMODATES UP TO 2 GUIDE PORTS. MOAG means Manual Off-Axis Guider. It allows you to guide your telescope to obtain sharp, round stars by guiding in front of your filters using unfiltered light in the same optical beam as your imaging camera.
  • Astrodon MMOAG Off Axis Guider

    $875.00$1,750.00
    GUIDE YOUR TELESCOPE IN FRONT OF YOUR FILTERS NEW DESIGN!! ACCOMMODATES UP TO 4 GUIDE PORTS. MOAG means Manual Off-Axis Guider. It allows you to guide your telescope to obtain sharp, round stars by guiding in front of your filters using unfiltered light in the same optical beam as your imaging camera. https://youtu.be/GZUUgeKMdkg
  • GUIDE YOUR TELESCOPE IN FRONT OF YOUR FILTERS NEW DESIGN!! ACCOMMODATES UP TO 4 GUIDE PORTS. MOAG means Manual Off-Axis Guider. It allows you to guide your telescope to obtain sharp, round stars by guiding in front of your filters using unfiltered light in the same optical beam as your imaging camera. https://youtu.be/GZUUgeKMdkg
  • Standard sizes are 1.25", 31mm, 50mm round, and 50mm square. The 1.25" is 27.5 mm of filter glass mounted in a 1.25" filter cell. The 31mm is 27.5mm of filter glass mounted in a 31mm ring. More information here: Unlike other Astrodon filters, the Photometric filters (Johnson-Cousins and Sloan) do not come as 36mm of unmounted glass. For those who want 36mm round for use in a 36mm filter wheel, 27.5 mm of filter glass can be mounted in our 36mm adapter. More information on 36mm mount here: We also have a limited quantity of 12mm and 25mm (call for pricing and availability). 100%-Coated for long-term durability and consistency of research with the highest throughput. https://youtu.be/t5NAIbV1l8o  
  • Standard sizes are 1.25", 31mm, 50mm round, and 50mm square. The 1.25" is 27.5 mm of filter glass mounted in a 1.25" filter cell. The 31mm is 27.5mm of filter glass mounted in a 31mm ring. More information here: Unlike other Astrodon filters, the Photometric filters (Johnson-Cousins and Sloan) do not come as 36mm of unmounted glass. For those who want 36mm round for use in a 36mm filter wheel, 27.5 mm of filter glass can be mounted in our 36mm adapter. More information on 36mm mount here: We also have a limited quantity of 12mm and 25mm (call for pricing and availability). All Astrodon Photometric filters are 100%-Coated for long-term durability and consistency of research with the highest throughput. NOTE: In Astrodon part numbers we pronounce the ' character (apostrophe)  as "prime" and the _ character (underscore) we pronounce as "sub"). So u'2_27R should be read as "u prime 2 sub 27 R". However, our dinosaur website software software chokes on ' (apostrophes) if they are in a SKU field part number. So we have replaced ' with ! in these places.  So the above part number (when used in a SKU field) on our website will appear as u!_27R. But it is really u'_27R. Again, this is due to our dinosaur software, but if you Google Astrodon you will find that Astrodon was a dinosaur with star shapes in the fossils...so appropriate, eh? In any event, forgive our software, move on, and be happy. https://youtu.be/t5NAIbV1l8o    
  • ASTRODON UVENUS FILTER
    • <0.01%T 285-305 nm; <0.1%T 420 – 1100 nm
    • Image the cloud structure of Venus and Jupiter with CCD cameras on a telescope.
    • Use for general UV photography (flowers, insects, forensics).
    https://youtu.be/t5NAIbV1l8o  
  • Carrying Handle with Farpoint D size Quick Mount Adapter

    This convenient Carrying Handle with included Farpoint Dovetail Accessory Adapter (FDA) provides a easy way to carry your telescope or other FDA mounted accessories.  
  • Carrying Handle for Farpoint D size Quick Mount Adapter

    Add this convenient handle to your Farpoint Dovetail Accessory Adapter (FDA) to provide a easy way to carry your telescope or other FDA mounted accessories.  
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    Closeout Pricing! $50

    Classic Lumicon 1.25 Inch Oxygen III Filter helps faint objects become much more visible against the blackened background of space.
  • Farpoint 1.25 Inch Cheshire Collimator is a simple tool that helps align the optical axes of the mirrors of a telescope, a process called collimation.  This precision-machined alignment tool for 1.25″ apertures is practically indestructible and requires no batteries.
  • Farpoint 1.25 Inch Collimation Kit includes a 1.25" stepped barrel 650nm laser collimator plus 1.25″ cheshire. These tools help align the optical axes of the mirrors of a Newtonian Reflector.  
  • Moisture is a menace to fine optics. Alleviate this threat with Farpoint 1.25 Inch Desiccant Cap for closed tube telescopes with 1.25" focusers.  
  • Farpoint 1.25 Inch Nosepiece-to-C/CS Mount Male Adapter is designed for imaging through telescopes using a video camera.
  • Farpoint 1.25 Inch T-Ring Prime Focus Adapter standard 1.25″ t-adapter fits on any telescope that uses a 1.25″ eyepiece focuser for prime focus photography.
  • Farpoint 1.5 lb Magnetic Bag Weight sticks securely to the steel optical tube assembly of many solid tube Dobsonians and is perfect for making fine balance adjustments. https://youtu.be/r-lrlETQfG0  
  • Farpoint 10 Inch Metric Universal Dovetail Plate
    Safely attach telescope optical accessories with Farpoint 10 Inch Metric Universal Dovetail Plate.  Machined of sturdy aluminum with a blue anodized finish, this Metric Universal dovetail bar is 10″ long with 60mm wide hole spacing for William Optics (and similar) scope rings and other general use purposes. Losmandy compatible.
  • Safely attach telescope optical accessories with Farpoint 108mm D Style Dovetail Rings. Includes two "D" Losmandy style 108mm rings.
  • Safely attach telescope optical accessories with Farpoint 108mm Vixen Dovetail Rings with Dovetail. Two 108mm Rings mounted on 8" long Vixen dovetail bar.