GSO 2" Photo-Visual Coma Corrector for Newtonian Telescopes

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GSO 2" Coma Corrector for fast Newtonian Telescopes
- 3-piece modular design (i) Optics in 2" nosepiece with 48mm male filter thread (ii) 2" eyepiece barrel that attaches to optical nosepiece, and (iii) M48 - T2 adapter ring
- Design optimized for use at f/4.5 but will work well from f/3 - f/6
- Reduce coma and field curvature
- Designed for visual and photographic use
- Magnification factor of only 1.1x
- Fully multicoated optics (4 elements / 2 lens groups) with a clear aperture of 43.9mm / 1.73"
- 2" nosepiece features smooth barrel and is threaded to accept standard 2" filters
- 2" eyepiece barrel features brass compression ring and dual large thumbscrews
- Back-focus spacing requirement is 75mm with a tolerance of +/- 5mm.
- For visual use, connect the 2" eyepiece barrel to the main optical nosepiece (as shown in photo 1 above). Additional spacers might be required at the bottom of your eyepiece (not included) to place the focal plane of the eyepiece at the required back-focus distance.
- For photo use, unscrew the 2" eyepiece barrel and attach the included M48-T2 ring to the main optical nosepiece (as shown in photo 3 above). Then attach your DSLR camera to the male T2 thread via a camera-specific T-ring (not included). Additional spacers will be required (not included) between the corrector and your camera's T ring depending on the camera's CCD chip location to ensure that your CCD plane is set to the correct back-focus distance from the corrector.
- For Canon/Nikon DSLR cameras (with a 55mm backfocus including a standard thickness T-ring), you will require an approx. 20mm long spacer (not included).
Specifications:
- Weight:
- Lower barrel with lens elements: 7.4 oz
- Upper eyepiece holder: 4.1 oz
- Complete unit for visual use: 11.8 oz
- T thread adapter: 0.3 oz
- Complete unit for photo use: 7.7 oz
Other Information
- Country of Manufacture: Taiwan
GSO 2" Coma Corrector for fast Newtonian Telescopes
- 3-piece modular design (i) Optics in 2" nosepiece with 48mm male filter thread (ii) 2" eyepiece barrel that attaches to optical nosepiece, and (iii) M48 - T2 adapter ring
- Design optimized for use at f/4.5 but will work well from f/3 - f/6
- Reduce coma and field curvature
- Designed for visual and photographic use
- Magnification factor of only 1.1x
- Fully multicoated optics (4 elements / 2 lens groups) with a clear aperture of 43.9mm / 1.73"
- 2" nosepiece features smooth barrel and is threaded to accept standard 2" filters
- 2" eyepiece barrel features brass compression ring and dual large thumbscrews
- Back-focus spacing requirement is 75mm with a tolerance of +/- 5mm.
- For visual use, connect the 2" eyepiece barrel to the main optical nosepiece (as shown in photo 1 above). Additional spacers might be required at the bottom of your eyepiece (not included) to place the focal plane of the eyepiece at the required back-focus distance.
- For photo use, unscrew the 2" eyepiece barrel and attach the included M48-T2 ring to the main optical nosepiece (as shown in photo 3 above). Then attach your DSLR camera to the male T2 thread via a camera-specific T-ring (not included). Additional spacers will be required (not included) between the corrector and your camera's T ring depending on the camera's CCD chip location to ensure that your CCD plane is set to the correct back-focus distance from the corrector.
- For Canon/Nikon DSLR cameras (with a 55mm backfocus including a standard thickness T-ring), you will require an approx. 20mm long spacer (not included).
Specifications:
- Weight:
- Lower barrel with lens elements: 7.4 oz
- Upper eyepiece holder: 4.1 oz
- Complete unit for visual use: 11.8 oz
- T thread adapter: 0.3 oz
- Complete unit for photo use: 7.7 oz
GSO 2" Coma Corrector for fast Newtonian Telescopes
- 3-piece modular design (i) Optics in 2" nosepiece with 48mm male filter thread (ii) 2" eyepiece barrel that attaches to optical nosepiece, and (iii) M48 - T2 adapter ring
- Design optimized for use at f/4.5 but will work well from f/3 - f/6
- Reduce coma and field curvature
- Designed for visual and photographic use
- Magnification factor of only 1.1x
- Fully multicoated optics (4 elements / 2 lens groups) with a clear aperture of 43.9mm / 1.73"
- 2" nosepiece features smooth barrel and is threaded to accept standard 2" filters
- 2" eyepiece barrel features brass compression ring and dual large thumbscrews
- Back-focus spacing requirement is 75mm with a tolerance of +/- 5mm.
- For visual use, connect the 2" eyepiece barrel to the main optical nosepiece (as shown in photo 1 above). Additional spacers might be required at the bottom of your eyepiece (not included) to place the focal plane of the eyepiece at the required back-focus distance.
- For photo use, unscrew the 2" eyepiece barrel and attach the included M48-T2 ring to the main optical nosepiece (as shown in photo 3 above). Then attach your DSLR camera to the male T2 thread via a camera-specific T-ring (not included). Additional spacers will be required (not included) between the corrector and your camera's T ring depending on the camera's CCD chip location to ensure that your CCD plane is set to the correct back-focus distance from the corrector.
- For Canon/Nikon DSLR cameras (with a 55mm backfocus including a standard thickness T-ring), you will require an approx. 20mm long spacer (not included).
Specifications:
- Weight:
- Lower barrel with lens elements: 7.4 oz
- Upper eyepiece holder: 4.1 oz
- Complete unit for visual use: 11.8 oz
- T thread adapter: 0.3 oz
- Complete unit for photo use: 7.7 oz
Other Information
- Country of Manufacture: Taiwan

GSO 2" Photo-Visual Coma Corrector for Newtonian Telescopes
