Celestron Technology Explained

Here’s how Celestron telescope technology can help your astronomy and astrophotography


All Star Polar Alignment technology


In order to do long-exposure astroimaging, an equatorially aligned telescope is necessary to properly track the motion of the sky. Precise tracking depends on an accurate polar alignment. Even with a visible star very near the North Celestial Pole (NCP), the true celestial pole can be very elusive to find without assistance.

That’s where All-Star Polar Alignment comes in. All-Star is Celestron’s exclusive, innovative polar alignment procedure – available on select Celestron computerised telescopes – that allows users to choose any bright star (not just one near the NCP) while the software calculates and assists with polar alignment.

Here’s how it works:

Once your telescope is aligned with two or more bright stars, All-Star allows you to choose any bright star listed in the NexStar hand control. This star will assist the software in correctly aligning your telescope’s mount with the North Celestial Pole.

Using the telescope’s Sync function, the mount will point to and centre a bright star with a high degree of accuracy. Once centred the mount will point the telescope to the exact position that the star should be, if the mount was precisely polar-aligned. When you adjust the mount’s altitude and azimuth controls to re-centre the star in the eyepiece, you are actually moving the mount’s polar axis to the exact position of the North Celestial Pole.


Here’s how Celestron telescope technology can help your astronomy and astrophotography

Celestron Advanced VX 11 Schmidt-Cassegrain Telescope


The Hibernate function


The sophisticated Hibernate function allows the telescope to maintain its star alignment night after night without needing to be re-aligned, thus making it an ideal instrument for a permanent observatory or for an observation periods over several nights whereby the telescope tripod isn’t moved.





With SkyAlign, setting up and using a computerised telescope is faster and easier than ever before. Point the telescope at three bright objects in the sky, and the telescope tells you what the objects are. You don’t need to know the names of the stars—you can even pick the Moon or bright planets!

SkyAlign is the simplest method to align a computerised telescope, providing ease of use for beginners while retaining the accuracy demanded by experienced users.

Input the date, time, and your location (GPS-equipped telescopes obtain all this information automatically) and then point the telescope at any three bright objects. There is no need to point the telescope north or to level the optical tube as in previous alignment methods: the initial position of the telescope is irrelevant.


Here’s how Celestron telescope technology can help your astronomy and astrophotography

Celestron CPC 925 GPS (XLT) Computerised Telescope


Internal GPS


Internal GPS receivers automatically download the date and time from orbiting satellites and pinpoint exact locations on Earth, eliminating the need for you to manually enter the date, time, longitude and latitude, allowing for a faster accurate setup procedure.


StarBright XLT coatings


StarBright XLT is Celestron’s revolutionary optical coating system that outperforms any other coating in the commercial telescope market. Celestron’s most popular Schmidt-Cassegrain telescopes come standard with this high-quality optical coating.


StarBright XLT Optical System Design:

One of the most important factors in the evaluation of a Schmidt-Cassegrain telescope’s optical system performance is its transmission, or the percentage of incoming light that reaches the focal plane. The design of the StarBright XLT system accomplishes a crucial objective: develop a coating system optimized for both visual use and for CCD/photographic imaging.

There are three major components that make up our StarBright XLT high-transmission optical system design:

Unique enhanced multi-layer mirror coatings made from precise layers of aluminium, SiO2 (quartz), TiO2 (titanium dioxide), and Si02 (silicon dioxide). Reflectivity is fairly flat across the spectrum, optimizing it for both imaging and visual observing.

Multi-layer anti-reflective coatings made from precise layers of MgF2 (magnesium fluoride) and HfO2 (hafnium dioxide). Hafnium—a rare element that costs nearly $2,000 per kilogram—gives us a wider band pass than the titanium used in competing coatings.

High-transmission water white glass is used instead of soda lime glass for the corrector lens. Water white glass transmits about 90.5% without anti-reflective coatings; that’s 3.5% better transmission than uncoated soda lime glass. When water white glass is used in conjunction with StarBright XLT’s anti-reflective coatings, the average transmission reaches 97.4%: an 8% improvement.

These three components of our StarBright XLT coatings result in one of the finest coatings available. The peak transmission for the systems is 89% at 520 nm. The overall system transmission is 83.5% averaged over the spectrum from 400 to 750 nm.


Here’s how Celestron telescope technology can help your astronomy and astrophotography

Celestron CGEM 1100 Computerised Telescope


EdgeHD optical Technology


EdgeHD is an aplanatic flat-field Schmidt optical system designed to produce aberration-free images with pinpoint stars all the way to the edge of the field of view of today’s largest imaging sensors and wide field eyepieces. EdgeHD virtually eliminates both field curvature and off-axis star coma, providing an astrograph-quality system at a fraction of the price of competitors.


True Astrograph Quality:

Many optical designs advertise themselves as “astrographs,” but only produce pinpoint stars across a curved focal plane. Even when focused sharply in the centre of the field of view, this curved plane cannot bring stars at the edges into focus. The wider the field of view, the more pronounced this defect becomes. This may be acceptable for some visual observing, but when a curved plane is paired with the flat sensor of a digital camera, stars become noticeably out of focus at the edges.

EdgeHD optics produce a focal plane more than three times flatter than a standard Schmidt-Cassegrain telescope and dramatically flatter than other competing coma-free designs, guaranteeing you visibly sharp stars all the way across the imaging sensor.


Mechanical Features of the Edge HD System:

The EdgeHD tube features an innovative mechanical design to ensure you get the most from your optics each and every night.

Mirror support: Flexible tension clutches hold the primary mirror in place and reduce image shift. The flexible rods hold the mirror in place without putting any force or pressure on the mirror assembly, keeping your target centred in the eyepiece or chip.

Tube vents: Cooling vents located on the rear cell allow hot air to be released from behind the primary mirror. Each vent has integrated micromesh filter guaranteed to let warm air out without letting dust in.

Fastar versatility: EdgeHD is the most versatile imaging telescope available today. At its native f/10, you can achieve the image scale necessary to capture the smallest of deep-sky objects. To increase your field of view without sacrificing performance, add the optional EdgeHD reducer lens. Each one is custom-made for your size EdgeHD optical tube and brings your focal ratio down to f/7. A Barlow lens provides additional magnification for high-resolution planetary, lunar, and solar imaging. And, of course, all EdgeHD optical tubes are Fastar-compatible for ultra-fast f/2 wide field imaging. Each EdgeHD tube is fitted with a removable secondary mirror and is Opto-mechanically aligned on a laser bench to ensure it is axially symmetric in any configuration.

Easy collimation: Guarantee ideal performance every time. Edge HD’s precision-machined mechanics and a spherical secondary mirror make collimation simple and accurate.


Here’s how Celestron telescope technology can help your astronomy and astrophotography

Celestron Advanced VX 11 Schmidt-Cassegrain Telescope



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