Astro-tech ED Triplet 106mm f/6.5 Refractor Telescope OTA w/2.7" Gray Focuser, Case-white, AT106
Item No. 658-12110
Manuf. No. Astro-Tech AT106
Astronomy Technologies Astro-Tech OTA 106mm f/6.5 FPL-53 ED triplet apochromatic refractor telescopes, AT106
The performance of this Astro-Tech 106mm FPL-53 ED (Extra-low Dispersion glass) triplet apochromatic refractor is outstanding, in keeping with Astro-Techııs well-deserved reputation for producing optically and mechanically excellent optics at sensible prices. A nearly four-page review of the AT106 in the September 2009 Sky & Telescope concluded simply ııthe Astro-Tech AT106 provides all the benefits of a first-class 4-inch apo but without the premium price. I highly recommend it."
All of the lenses in the air-spaced triplet optics of the AT106 are fabricated from Ohara glass (Ohara is Japanııs 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 AT106 images are free of all vestiges of the annoying faint color halos around bright objects visible in lesser scopes - despite the Astro-Techııs fast focal ratio, and even at very high magnifications.
Features of this Telescope
Apochromatic triplet refractor optics: 106mm (4.17") aperture, 690mm focal length, f/6.5 focal ratio three-lens 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 Japanııs premier manufacturer of specialized optical glass.
Collimatable lens cell: The push/pull lens cell is fully collimatable in the field for peak performance. A simple optional Cheshire eyepiece and your own eyes are all you need.
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. Itııs 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 within 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 neighborııs backyard security light. The tube measures a compact 24" long with the dew shield retracted, and only 27.5" long with it extended. A lock knob under the dew shield locks it firmly in place when fully extended.
Dual-speed rotating 2.7" Crayford focuser: The precision-made Crayford 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 DSLR 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 focuser can be rotated 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. Simply loosen a knob on the top of the focuser, rotate the focuser to whatever angle is most convenient for you, and then tighten the knob to lock the focuser at the desired angle.
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 under 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 wonııt 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 scopeııs exceptional optical performance to your eye.
A standard equipment 1.25" accessory adapter slips into the 2" eyepiece holder 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" 99% reflectivity 46-layer dielectric coated diagonal (#AT1D). It was named a Sky & Telescope Hot Product for 2007.
Camera angle adjuster: In addition to the entire focuser rotating, the focuser drawtubeııs 2" eyepiece/accessory holder is itself a built-in camera angle adjuster that lets you quickly make final small adjustment tweaks to the angle of your camera or star diagonal without having to disturb the heavier focuser proper. This camera angle adjuster is standard equipment, not an optional extra-cost accessory, as it is with some other scopes. A knob on the 2" eyepiece/accessory holder lets you unlock the accessory holder, rotate it to the desired final angle, then lock it in place at whatever angle is most convenient for you. Many observers will find this camera angle adjuster to be even more convenient that the focuser rotation system and will use this method of adjusting the viewing angle exclusively.
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 AT106. The focuser and trim are anodized gun metal grey.
Tube rings: No tube rings are supplied for the 114mm o. d. optical tube, as some observers may already have rings for this popular tube size. If rings are needed, however, optional 114mm Astro-Tech #AT114R hinged tube rings are readily available.
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.
This Astro-Tech AT106 refractor has:
- 106mm f/6.5 fully multicoated air-spaced triplet apochromatic optics using an FPL-53 ED element and all Ohara glass
- collimatable lens cell
- rotating dual-speed 2.7" Crayford focuser with 10:1 ratio fine focusing
- both 2" and 1.25" brass compression ring eyepiece holders
- retractable lens shade/dew shield
- long-lasting white paint finish with anodized grey trim
- aluminum-frame foam-fitted hard case
- excellent Sky & Telescope review
- two-year warranty
- Highest Useful Magnification 215x
- Visual Limiting Magnitude 12.6
- Focal Length 690 mm
- Focal Ratio f/6.5
- Resolution 1.09 arc seconds
- Aperture 4.17"
- Weight 11 lbs.