Meade AT 127EDT instruction sheet Objective Lens Cover, Resolving Power Dawes’ Limit

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AT 127EDTfrom Astronomy Technologies

Thank you for choosing this Astro-Tech AT127EDT ED triplet refractor.

The lenses in your scope’s 950mm f/7.5 air-spaced triplet optics include an advanced ED (Extra-low Dispersion) glass element to give you images that are virtually color-free, even at very high powers. Thanks to its computer-optimized optical design, quality ED glass, and high transmission multicoatings, the optical

performance of your AT127EDT is very impressive for its very reasonable price.

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 AT127EDT before using it for the first time.

PARTS OF THE AT127EDT

Retractable

dew shield	Carrying handle/accessory mount
	Tube ring	2” star
	lock knob
Tube		diagonal
	(1 of 2)
rings
	Finderscope focusing ring
Finderscope focus lock ring
	Illuminator
	on/off/brightness	1.25”
	control
Vixen-style		eyepiece
dovetail	Finderscope	holder
8x50mm	collimating
finderscope	screw (1 of 3)	Mounting point
Carrying handle/accessory mount		for finder

Finderscope illuminator	Fine focus
Crosshair focus lock ring	knob
Crosshair focusing ring
Lock knob for
focuser drawtube

			Left coarse	2” accessory		2” accessory Right coarse
			focus knob	lock knob		holder	focus knob
	Astro-Tech AT127EDT ED Triplet Refractor Specifications
Aperture		127mm (5”)	Lens Shade Outer Diameter				156mm
Focal Length		950mm	Objective Lens Cover		.....................		thread-in metal
Focal Ratio		f/7.5	Tube Diameter				130mm o. d.
Objective Type		air-spaced triplet	Tube Rings .... dual split hinged rings with Vixen-style
Optical Coatings		fully multicoated	dovetail and carrying handle/accessory mount
Resolving Power (Dawes’ Limit)		0.91 arc seconds	Tube Length (lens shade retracted)				33.25” (845mm)
Visual Limiting Magnitude		13.0 maximum	Tube Length (lens shade extended)				37.25” (946mm)
Light Grasp (versus the eye)		329x	Optical Tube Weight			18.75 lbs. (8.52 kg)
Field Stops	two internal knife-edge baffles		Case		aluminum-frame foam-fitted
Focuser	dual-speed rack and pinion			lockable hard case, with carrying handle
	with 10:1 reduction ratio fine focus		Case Dimensions				36.5” x 14.5” x 10”
and 2” and 1.25” compression ring eyepiece holders			Lowest Usable Power		............	19x (50mm eyepiece)
Focuser Travel		4.25” (108mm)	Highest Practical Power			........ 238x (4mm eyepiece)
Finder	8 x 50mm with erect right-reading image		Theoretical Maximum		........	271x (3.5mm eyepiece)
and variable brightness illuminated crosshair reticle			Supplied Accessories			10mm and 20mm 1.25”
Lens Shade		retractable	eyepieces; enhanced 99% reflectivity 2” diagonal