To correct the field of view on their N-Series Astrographs, ASA uses correctors designed by Philipp Keller. All correctors have sufficient backfocus to connect to all popular camera systems.
ASA 2" Reducer Corrector
Depending on the corrector, systems can be used at f/3.6 or shortened to f/2.75. Alternatively, N-Series Astrographs can be extended to f/6.8. The photographer can decide which focal length to use, depending on the object they are imaging, the seeing conditions, and other considerations such as wind.
For example, an ASA Astrograph N 8"/f3.6 with a focal length of 730 mm can also be used at 558mm (f/2.75) or as a 1380mm, f/6.8 system. All ASA correctors are available separately and can be used with other Newtonian telescopes.
ASA 2" Reducer Corrector Specifications...
- Corrected Field: 22mm
- Backfocus: ca. 65 mm
- Additional Information
SKU A2-2KORRR Manufacturer ASA Barrel Size 2" Warranty Not Supplied By Manufacturer
- Included Items
- ASA 2" Reducer Corrector
- Questions & Answers
Product QuestionsI've seen this used with GSO/TPO newts. However looking at ASA's datasheet it doesn't give any info on the back focus for a 8"/200mm scope. Is there formula for figuring the correct back focus respective size of the scope?Question by: Jonathan on Nov 4, 2014 8:26:02 AMASA notes a nominal back focus of 65mm for any size fast Newtonian around f/3.5-f/4. A slower or smaller scope will do better a smidge closer (undercorrected) and a larger and/or faster scope will do better with the camera a bit farther (overcorrected), but 65mm +/- 1mm should give acceptable results with most 8" Newts.Answer by: Chris (Admin) on Nov 6, 2014 8:47:43 AM
- Support / Downloads
- Related Blog Posts