Astro-Physics introduced the redesigned 92-mm f/6.65 Stowaway at Northeast Astro-Imaging Conference on April 18, 2018. Long-time astronomers will recall that it previously offered f/5 and f/7 Stowaway refractors from 1999-2002, which are cherished today for their portability and performance.
Indeed, A-P’s own Stowaway has traveled with its team to star-gaze in far off places, as well as to watch whales, boats, birds and other wildlife. While observing the solar eclipse in August 2017 from Wyoming, they had so much fun with their original 92-mm Stowaways, they decided to make another production run.
This triplet lens scope has the same extraordinary quality that you have come to expect from Astro-Physics with a few new exciting features thrown in, including dramatic deep-sky imaging with its optional Prime Focus Field Flattener, a silky-smooth 2.5-inch Starlight Instruments Feather Touch focuser with dual-speed mechanism (the dual-speed feature is particularly advantageous for critically focusing at focal ratio this fast), and a digital focusing system is available for imaging.
The rotating focuser enables you to frame your photos for optimal, artistic composition, and the compact, lightweight tube assembly, augmented by the fully-retractable, felt-lined dew shield, assures an easy fit into your carry-on luggage.
The optics feature three air-spaced elements, with broad band multi-coatings on all surfaces. The design was made using the latest version of ATMOS lens design program. The optimization was chosen for the polychromatic Strehl ratio to be above 90 percent for the entire visual spectrum, with a peak value of 99.8 percent at the visual peak. The result is unprecedented color correction. Visually, the scope shows sharp, contrasty images without color fringing, with well-corrected high-power oculars.
The custom field flattener design achieves wide-band color correction that extends into the violet regions, with diffraction-limited performance designed for the most demanding modern astronomical cameras. This is especially important for the latest CMOS chips, which have their highest sensitivities in the violet part of the spectrum and will show large blue halos with lesser optical designs. The 92-mm, with dedicated field flattener, produces sharp images at all wavelengths without blue halos or bloated stars.