Meade instruction sheet Astro-tech, Parts of the AT111EDT

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astro-tech

AT 111EDT from Astronomy Technologies

Thank you for choosing this Astro-Tech AT111EDT high-quality apochromatic triplet refractor.

The lenses in your scope’s 777mm f/7 air-spaced triplet optics use Ohara glass exclusively, from Japan’s finest glass manufacturer. They include an advanced ED (Extra- low Dispersion) element to give you images that are virtually color-free, even at very high powers. Thanks to its computer-optimized optical design, top quality ED

glass, and high transmission multicoatings, the optical performance of your AT111EDT is exceptional indeed.

This instruction sheet will provide you with information on how to get the most out of your new Astro-Tech refractor, and how to properly maintain it so it can give you a lifetime of observing enjoyment.

Please familiarize yourself with the parts and functions of your AT111EDT before using it for the first time.

PARTS OF THE AT111EDT

Locking knob for 360°

Mounting shoe for

 

 

rotatable focuser

optional finder

Focusing

 

 

 

 

Lock knob for

2”

 

scale on

 

focuser

focuser drawtube

eyepiece

 

 

drawtube

 

 

holder

1.25”

Retractable dew shield

 

 

 

 

 

 

 

eyepiece

 

 

 

 

 

 

 

 

holder

 

 

 

 

 

 

 

 

Fine

 

 

 

 

 

 

 

focus

 

 

 

 

 

 

 

knob

Dust cover

Brass compression ring

Left coarse

2”

 

 

 

Right

 

 

 

 

 

 

 

 

 

 

eyepiece

 

 

 

 

 

focus knob

 

 

 

coarse

 

 

holder

 

 

 

 

 

 

1.25”

 

focus

 

 

 

 

 

 

 

2” eyepiece

 

 

knob

 

 

 

eyepiece

 

 

 

 

 

 

lock knob

 

holder

 

 

 

1.25” eyepiece

1.25”

 

 

 

 

 

 

lock knob

 

 

 

1.25” eyepiece

 

eyepiece

 

 

 

 

 

holder

 

 

 

 

lock knob

 

 

 

 

 

 

 

 

Astro-Tech AT111EDT Apochromatic ED Triplet Refractor Specifications

Aperture

 

111mm (4.4”)

Finder

optional; mounting shoe provided for

Focal Length

 

777mm

Astro-Tech multiple reticle finder or similar finder

Focal Ratio

 

f/7

Lens Shade

 

retractable

Objective Type

 

air-spaced triplet

Lens Shade Outer Diameter

.......................

150mm

using all-Ohara glass, including an ED element

Objective Lens Cover

slip-on metal

Optical Coatings

 

fully multicoated

Tube Diameter

124mm o. d.

Resolving Power (Dawes’ Limit)

1.04 arc seconds

Tube Length (lens shade retracted)

23.75” (603mm)

Visual Limiting Magnitude

..............

12.7 maximum

Tube Length (lens shade extended)

........ 28” (711mm)

Light Grasp (versus the eye)

251x

Optical Tube Weight

14.65 lbs. (6.66 kg)

Field Stops

three knife-edge baffles

Case

aluminum-frame foam-fitted

Focuser

dual-speed rack and pinion

 

lockable hard case, with carrying handle

 

with 11:1 reduction ratio fine focus;

Case Dimensions

28” x 10.25” x 9”

360° rotating camera angle/observing angle adjuster;

Lowest Usable Power

19.4x (40mm eyepiece)

and 2” and 1.25” compression ring eyepiece holders

Highest Terrestrial Power

86x (9mm eyepiece)

Focuser Travel

 

5.4” (138mm);

Highest Practical Power

194x (4mm eyepiece)

millimeter scale on drawtube for repeatable focus

Theoretical Maximum

222x (3.5mm eyepiece)

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Contents Parts of the AT111EDT Astro-techAT 111EDT from Astronomy Technologies From Astronomy Technologies, 680 24th Avenue SW, Norman, OK

AT111EDT specifications

The Meade AT111EDT is a premium apochromatic refractor telescope that stands out for its exceptional optical performance and robust design, making it an excellent choice for both amateur astronomers and advanced astrophotographers. With a focal length of 850mm and a fast f/7.6 ratio, this telescope is particularly well-suited for capturing breathtaking images of a variety of celestial objects, from the moon and planets to deep-sky wonders.

One of the standout features of the AT111EDT is its advanced optics. It utilizes a triplet design incorporating two extra-low dispersion (ED) glass elements. This configuration minimizes chromatic aberrations, resulting in sharp, color-accurate images that are critical for both visual observation and astrophotography. The high-quality multi-coatings applied to its optics further enhance light transmission, offering improved brightness and contrast.

The telescope is built with a sturdy, yet lightweight aluminum tube that aids in portability, making it an excellent choice for those who enjoy traveling to darker skies. The mounting rings and Vixen-style dovetail plate ensure secure attachment to a variety of mounts, allowing for stability during observations and imaging sessions.

In terms of convenience, the AT111EDT features a 2-inch Crayford-style focuser with a 1.25-inch adapter, offering smooth and precise adjustments for fine focusing. This is crucial when working with delicate astrophotography setups, where even the slightest shift can impact the final image quality. The focuser also includes a compression ring, preventing potential damage to your eyepieces or cameras.

The telescope's design is not only focused on functionality but also aesthetics. It features a sleek and stylish appearance that appeals to the modern user. Additionally, the AT111EDT is compatible with a wide range of accessories, including field flatteners and reducers, allowing users to customize their setup according to their specific needs.

With its impressive features and high-quality construction, the Meade AT111EDT represents a blend of portability and performance, making it an ideal instrument for astronomers who seek to explore the cosmos in detail. Whether for deep-sky imaging or enjoying the grandeur of planetary views, the AT111EDT delivers a remarkable observing experience that is hard to match.