The performance of this Astro-Tech 130mm FPL-53 ED (Extra-low Dispersion glass) triplet apochromatic refractor is superb, in keeping with Astro-Tech's well-deserved reputation for producing optically and mechanically excellent small optics. All of the lenses in the air-spaced triplet optics of the AT130 are fabricated from Ohara glass (Ohara is Japan's premier manufacturer of specialized optical glass), including the first-quality FPL-53 center element.
The result of using the best possible glass is the finest possible control of spurious color. The AT130 images are free of all vestiges of the annoying faint color halos around bright objects visible in lesser scopes - despite the Astro-Tech's fast focal ratio, and even at very high magnifications.
Those exceptional optics come in a finely-machined body with a newly-designed dual speed 2.7" Crayford focuser with a microfine 10:1 fine-focusing ratio. The focuser can rotate a full 360 degrees to put your camera or eyepiece in the most comfortable observing position. The supplied 2" and 1.25" eyepiece holders use non-marring brass compression rings that won't scratch your eyepiece barrels. The Astro-Tech AT130 has a retractable lens shade and comes in a locking aluminum-frame carrying case.
Features
- Collimatable apochromatic triplet refractor optics - 130mm (5.12") aperture, 780mm focal length, f/6 focal ratio. Three-lens air-spaced optical system using the finest quality FPL-53 ED (Extra-low Dispersion glass) element to reduce spurious color halos and fringing to vanishingly low levels. All three lens elements are made from the finest quality Ohara glass. Ohara is well-known as Japan's premier manufacturer of specialized optical glass. The lens cell is fully collimatable for peak performance.
- Fully multicoated optics - The triplet objective lens has the latest state-of-the-art antireflection multicoatings on all air-to-glass surfaces for high light transmission and excellent contrast. This can easily be seen by looking into the objective lens of the scope. Virtually no reflection of your face will be seen. It's a sure sign that the high transmission coatings are doing their job, by letting virtually all the light enter the scope, rather than reflecting some light back to your eye.
- Internal light baffles - Contrast-enhancing knife-edge light baffles in the lens shade and the optical tube provide truly dark sky backgrounds and high terrestrial contrast. The edges of the lenses are blackened to reduce internal reflections and further improve image contrast.
- Dew shield - A self-storing retractable dew shield slows the formation of dew on the lens in cold weather to extend your undisturbed observing time. It also improves the contrast, similar to the effect of the lens shade on a camera lens, when observing during the day or when there is excessive ambient light at night, such as a neighbor's backyard security light.
- Dual speed microfine 2.7" Crayford focuser - The precision-made focuser has dual-speed focusing. There are two coarse focusing knobs. The right knob also has a smaller concentric knob with 10:1 reduction gear microfine focusing ratio. This provides exceptionally precise image control during high magnification visual observing and critical 35mm or CCD imaging. The focus knobs have ribbed gripping surfaces so they are easy to operate, even while wearing gloves or mittens in cold weather.
The 2.7" focuser drawtube terminates in a built-in camera angle adjuster as standard equipment. It is not an optional extra-cost accessory, as it is with some other scopes. The camera angle adjuster lets you rotate the focuser to line up a camera in either a landscape or portrait orientation (or any orientation in between), as well as put a star diagonal and eyepiece into the most comfortable observing position. A knob on the camera angle adjuster lets you lock the focuser at whatever angle is most convenient for you.
The 80mm (3.15") travel 2.7" diameter focuser drawtube has a scale marked in 1mm increments so you can note individual focuser positions for easy return to the correct focus when switching between visual use and photography. The focuser has adjustable tension to accommodate varying equipment loads. A separate lock knob on top of the focuser lets you lock in your photographic focus.
- 2" and 1.25" compression rings accessory/eyepiece holders - The 2.7" drawtube terminates in a 2" accessory/eyepiece holder that uses a non-marring soft brass compression ring to hold a 2" star diagonal and accessories in place. The compression ring won't scratch the barrel of your star diagonal and accessories as an ordinary thumbscrew can. For 2" eyepiece use, an Astro-Tech guaranteed 1/10th wave peak-to-valley accuracy 2" quartz star diagonal (#AT2DQ) is recommended to deliver all of the scope's exceptional optical performance to your eye. A standard equipment 1.25" accessory/eyepiece adapter slips into the 2" accessory holder on the focuser drawtube to let you use a 1.25" star diagonal or image erecting diagonal. Like the 2" eyepiece holder, the 1.25" adapter also uses a non-marring soft brass compression ring to hold 1.25" star diagonals and accessories in place. If you are partial to 1.25" eyepieces and need an outstanding diagonal for this scope, consider the Astro-Tech 1.25" dielectric diagonal (#AT1D). It was named a Sky and and Telescope Hot Product for 2007.
- Tube finish - The optical tube and lens shade are finished in a durable high gloss automotive-style white paint, the same as that used on scopes double the price of the AT130. The focuser and trim are anodized gun metal grey.
- Other supplied accessories - A slip-on metal dust cap is standard. There is no finderscope provided, but a threaded hole on the upper left side of the optical tube permits the installation of an optional multiple reticle red dot finder (#ATF). The finder mounting hole is sealed with a slotted-head threaded insert to prevent the entrance of dust into the scope when no finder is installed.
- Shipping/ storage case - The scope comes in a foam-fitted aluminum-frame locking hard case with carry handle. Astro-Tech is one of the very few manufacturers to provide a case at no charge for protection during shipping and as a storage convenience when the scope is not in use. Unfortunately, FedEx, UPS, and the Postal Service are very good at treating packages roughly. Occasionally, your scope can arrive in perfect condition, but with the walls of the shipping case dented in transit from rough handling, or the aluminum frame sprung, rendering the appearance of the case less than pristine. Damage to the shipping case in such instances is not covered by warranty.
