Celestron NexStar 4SE Maksutov

Celestron's NexStar 4SE 125mm f/13 Maksutov-Cassegrain GoTo Telescope is a powerful, versatile, and user-friendly catadioptric-style scope that can be used for observing everything from the Moon and planets to bright deep-sky objects like stars, galaxies, and nebulae. Using Celestron's proprietary StarBright XLT multi-coating system, light transmission is increased throughout the entire optical path with anti-reflection multi-coated lenses, highly reflective multi-coated mirrors, and crown optical glass elements. Similar to their Schmidt cousins, the Maksutov design exchanges the conventional front corrector plate with a convex meniscus lens, which results in a smaller secondary mirror—limiting obstruction and increasing contrast, while eliminating the need for periodic collimation. While the focal ratio is a relatively slow f/13, the scope's optical performance, added to the mount's precision tracking system and integrated equatorial wedge, allows it to be a competent astrophotography/imaging platform for the Moon and planets.

Driving the dual servo motors on the mount is the brain of the NexStar 4SE: the iconic NexStar+ computer hand controller. Packed with 40,000+ celestial objects, it can hold up to 100 additional user-defined destinations and is updatable via the Celestron website. It has multiple alignment procedures to get you observing fast—including the super-easy SkyAlign system. Capable of being used in the Northern or Southern Hemispheres, the NexStar has sidereal, lunar, and solar tracking speeds to accurately follow near- and deep-sky objects, plus nine slew speeds and the ability to automatically trigger a camera's shutter release for Fastar or piggyback wide-field photography or conventional prime-focus astrophotography.

Performance

4" (102mm) aperture

f/13 focal ratio

1325mm focal length

Maksutov-Cassegrain optical system

Front convex meniscus lens corrects spherical and chromatic aberrations and comas (off-axis aberration) across the entire field of view

Smaller secondary mirror versus Schmidt-Cassegrain reduces obstructions and increases the contrast

BK7 optical glass primary mirror

StarBright XLT optical coatings: Multi-layer aluminum/SiO2 (quartz)/TiO2 (titanium dioxide) mirror coatings with flat reflectivity across the light spectrum for both astrophotography/astroimaging and visual observation

Multi-layer MgF2 (magnesium fluoride) and HfO2 (hafnium dioxide) anti-reflective lens coatings

High-transmission water white glass corrector lens with 97.4% light transmission

Resolution: Rayleigh: 1.36 arcsec / Dawes: 1.14 arcsec

Secondary mirror obstruction: 1.25", 34.4% by diameter, 11% by area

Internal 90° flip mirror: With the mirror flipped up, the 90° angle puts the head in a comfortable viewing position when the scope is pointed at or near the zenith; lay the mirror down to direct light to the visual back for astrophotography/imaging

NexStar+ Computer Controller

2-line, 16-character LCD display

19 fibre optic backlit red LED buttons

Database of over 40,000 celestial objects plus 100 user-defined

Automatically slew to planets, stars, constellations, and a variety of catalogues

Camera control: For piggyback wide-field or conventional astrophotography through the optical tube assembly, the controller can automatically trigger the shutter release to capture the image

Anti-backlash compensation programs out play between gears for more precise tracking

Tour Mode: Shows a selection of the most popular objects for the time and date you are observing

Constellation Tour: This allows you to take a tour of all the best objects within a particular constellation

Alignment procedures: SkyAlign, Auto 2-Star, 1-Star, 2-Star, and Solar System

SkyAlign alignment: Takes minutes, with minimal effort or experience—point the telescope at three bright objects in the sky, and the telescope does the rest

Nine slew speeds: 4°/sec, 2°/sec, 1°/sec, 0.5°/sec, 2x, 4x, 8x, 16x, and 32x

Sidereal, Solar, and Lunar tracking rates for observing the fast-moving Moon, to slower-moving deep-space subjects

Tracking modes: Alt-Az (default, for general GoTo use), EQ North (use for long-exposure astrophotography in Northern Hemisphere with EQ wedge engaged), EQ South (use for long-exposure astrophotography in Southern Hemisphere with EQ wedge engaged), Off (no tracking when using as a terrestrial spotting scope)

RS-232 communication port allows for computer control

Flash updatable via the Celestron website

Database Details:

Solar system objects including the Sun, Moon, and planets

Named objects

Stars: Asterism, variable stars, double stars, named stars

Caldwell catalogue

Messier catalogue

NGC catalogue

SAO catalogue

Constellations

Mount & Tripod

Mount:

Single-fork alt-az

Dual-axis servo motors allow for precise tracking with virtually no vibration

Motor resolution: 0.26 arcsec

Optical encoders track mount movement to improve tracking and GoTo accuracy while allowing the mount to maintain alignment when moved manually

Communication ports: Autoguider port, Aux port, hand controller

Runs on eight user-supplied AA batteries or an optional 12 VDC power supply

Tripod:

Stainless steel legs

Adjustable height accommodates a variety of observation positions or users

Built-in equatorial wedge enables more precise tracking accuracy during long-exposure astrophotography

The tray holds accessories such as eyepieces and filters and adds stability and vibration reduction

Weight: 10 pounds

Included Accessories

Eyepiece:

1.25" diameter barrel

25mm focal length produces 53x magnification

Anti-reflection multi-coated glass improves colour rendition and contrast

Threaded barrel accepts most 1.25" astronomical filters

Fold-down rubber eyecup for use with or without eyeglasses

StarPointer Finder

Projects a single red dot in line of sight

Unmagnified to make finding objects faster and easier

Used primarily for the alignment process