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Showing 1–12 of 92 results
  • Astrodon 3 nm Narrowband Filter, 36mm, – HA3_36R-2000138 (2nd Quality Discount)

    $748.00 $654.00

    This individually serialized filter, HA3_36R-2000138, has been scored at 9.9 and has a 12.5% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

    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

     

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  • Astrodon 3 nm Narrowband Filter, 36mm, SII3_36R-2000151 (2nd Quality Discount)

    $748.00 $635.00

    This individually serialized filter, SII3_36R-2000151, has been scored at 9.8 and has a 15% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

    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

     

     

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  • Astrodon Photometrics Johnson-Cousins Filter, 1.25″ Mounted, edge-blackened- B***_31R-200097 (2nd Quality Discount) (Copy)

    $226.00 $199.00

    This individually serialized filter, B***_31R-200097, has been scored at 9.925 and has a 11.88% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

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  • Astrodon Photometrics Johnson-Cousins Filter, 31mm Mounted, edge-blackened- B***_31R-200097 (2nd Quality Discount)

    $226.00 $199.00

    This individually serialized filter, B***_31R-200097, has been scored at 9.925 and has a 11.88% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Read more
  • Astrodon Photometrics Johnson-Cousins Filter, 1.25″ Mounted, edge-blackened- B***_27R-200096 (2nd Quality Discount)

    $216.00 $193.00

    This individually serialized filter, B***_27R-200096, has been scored at 9.975 and has a 10.63% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Read more
  • Astrodon Photometrics Johnson-Cousins Filter, 1.25″ Mounted, edge-blackened- B***_27R-200095 (2nd Quality Discount)

    $216.00 $187.00

    This individually serialized filter, B***_27R-200095, has been scored at 9.875 and has a 13.13% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Read more
  • Astrodon LRGB Gen2 Blue Tru-Balance Filter 50mm Square, B2_50S-200094 (2nd Quality Discount)

    $403.00 $302.00

    This individually serialized filter, B2_50S-200094, has been scored at 9.4 and has a 25% discount (edge crack). Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Add to cart
  • Astrodon LRGB Gen2 Blue Tru-Balance Filter 50mm Square, B2_50S-200092 (2nd Quality Discount)

    $403.00 $363.00

    This individually serialized filter, B2_50S-200092, has been scored at 9.9 and has a 12.5% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Add to cart
  • Astrodon LRGB Gen2 Blue Tru-Balance Filter 50mm Square, B2_50S-200093 (2nd Quality Discount)

    $403.00 $357.00

    This individually serialized filter, B2_50S-200093, has been scored at 9.95 and has a 11.25% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Add to cart
  • Astrodon LRGB Gen2 Blue Tru-Balance Filter 50mm, B2_50R-200091 (2nd Quality Discount)

    $318.00 $286.00

    This individually serialized filter, B2_50R-200091, has been scored at 9.95 and has a 11.25% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Add to cart
  • Astrodon LRGB Gen2 Blue Tru-Balance Filter 50mm, B2_50R-200090 (2nd Quality Discount)

    $318.00 $286.00

    This individually serialized filter, B2_50R-200090, has been scored at 9.95 and has a 11.25% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Add to cart
  • Astrodon LRGB Gen2 Blue Tru-Balance Filter 50mm, B2_50R-200089 (2nd Quality Discount)

    $318.00 $286.00

    This individually serialized filter, B2_50R-200089, has been scored at 9.95 and has a 11.25% discount. Astrodon 2nd Quality filters are still covered by our warranty for longevity, but are otherwise sold “as is” and are not returnable.

    Astrodon 2nd Quality Filters are sold at a discount. 2nd Quality Filters are individually evaluated and graded for edge chips, scratches, pinholes and inclusions according to the standards set below:

    Edge Chips: Score 1 point for each edge chip. Score 1 additional point for each edge chip that extends into the filter more than 2mm from the edge.

    Pin holes: Score 1 point for each pinhole. Score an additional point for each pinhole that is “large”.

    Scratches: Score 1/2 point for each scratch.

    Inclusions: Score 1/2 point for each inclusion.

    Subtract the sum of the points from 100 and divide by 10. This is the filter score.

     

    Add to cart