Celestron Astro Fi 6 Schmidt-Cassegrain telescope review

The Celestron Astro Fi 6 is an enjoyable and lightweight setup that can be controlled via your smartphone or tablet

Our rating 
4.5 out of 5 star rating 4.5
Price correct at time of review
Celestron Astro Fi 6 Schmidt-Cassegrain telescope. Credit: BBC Sky at Night Magazine

With the advent of modern smartphones it wasn’t long before Celestron brought out its Astro Fi range where, using Celestron’s free SkyPortal app, you can fully control an altazimuth Go-To computerised telescope without the need for the traditional handset.


The Astro Fi 6 is an SCT with a focal length of 1,500mm that gives a focal ratio of f/10. The optics have Celestron’s proprietary StarBright XLT coatings, giving better contrast for planetary and lunar observations, along with higher light transmission for deep-sky targets.

The long focal length fits neatly into a compact, lightweight tube. This is easy to lift onto, and attach to, the mount.

Complementing the optics is a ‘visual back’, allowing the supplied 1.25-inch star diagonal to be used along with two Kellner eyepieces, 25mm and 10mm, giving a good range of magnification of 60x and 150x.

A StarPointer finderscope (red dot finder) and a basic, but useful, smartphone holder that can accommodate most smartphone brands is also provided.

Celestron Astro Fi 6 Schmidt-Cassegrain telescope. Credit: BBC Sky at Night Magazine

Child friendly

The mount is a single arm, computerised Go-To altazimuth mount with a Vixen- (or CG-5-) style adaptor. It’s easily fitted to the aluminium tripod via the captive knob under the top of the tripod.

A battery pouch for 8xAA batteries is provided (although batteries are not included) and the mount can also be powered by a power tank.

The tripod has extendable legs, providing a good range of adjustment and making it ideal for children when it’s positioned at a low height.

As with other telescopes in the Astro Fi series, the Fi 6 is not supplied with a handset. Instead, the mount incorporates the Astro Fi Wi-Fi network to allow control via a smartphone or tablet.

By downloading the Celestron SkyPortal app (android and iOS) and connecting to the mount’s Wi-Fi signal, you can connect and align with your smart device.

We used our iPhone 7+ and iPad Pro to connect with no difficulty, using SkyPortal which is based on the SkySafari app.

Once aligned there is plenty to explore each night, with 120,000 stars and over 200 deep-sky objects to choose from, along with planets, moons, asteroids and comets.

We also found we could connect using SkySafari Pro 6,
so if your system supports these apps then you should be able to connect and operate the scope.

Celestron Astro Fi 6 Schmidt-Cassegrain telescope. Credit: BBC Sky at Night Magazine

Bright ideas

Optically, we enjoyed crisp views of Jupiter and Saturn despite their low altitudes, with the Cassini Division just discernible and the belts of Jupiter and its Galilean moons seen easily.

Our Moon was detailed, with the 10mm eyepiece giving good views as we explored the waning gibbous Moon replete with craters, including a view of Theophilus, Cyrillus and Catharina.

Using the app we took a tour of the brighter Messier objects, including the stunning Great Globular Cluster, M13, the Ring Nebula, M57, the Dumbbell Nebula, M27, the Wild Duck Cluster, M11 and the Omega Nebula, M17.

We could catch a view of M81 and M82 – the galaxy pair in Ursa Major – just fitting in the view of the 25mm eyepiece. We also enjoyed a good colourful view of Albireo, and with the 10mm eyepiece we could make out the three components of Iota (ι) Cassiopeiae.

We also explored what the smartphone holder could capture with the 25mm eyepiece. We imaged deep-sky targets, mainly star clusters that were bright enough to capture with our iPhone using the NightCap Camera app.

We found it was best to connect the mount using our tablet, as this left the smartphone free for imaging.

If you don’t wish to use a smart device to control the system, you can buy the optional handset, but we found it was a very enjoyable experience controlling the Astro Fi 6 with our smart devices.

In fact, it proved itself as the next step in smart telescope control.

Lightweight and versatile

We were impressed with how easy the Astro Fi 6 SCT was to assemble, set up and use for a variety of purposes.

With a tube weight of just 2.17kg, mount weight of 2.3kg and tripod at 2.3kg, each is just over a couple of bags of granulated sugar in weight.

The optical tube is just 406mm long with a diameter of 155mm, making it compact for an f/10 system.

This makes it an ideal setup for youngsters while giving a decent size of aperture to allow good views of so many objects.

An altazimuth Go-To system is traditionally best for visual observations, especially of the planets and the Moon, but the brighter deep-sky targets were also seen well in our tests.

Throw in the smartphone control, and basic but useful smartphone holder, and the system takes on a new role for astrophotography.

We captured short exposures with our smartphone of the Moon and brighter deep-sky objects too, showing just how versatile it really is.

Celestron Astro Fi 6 Schmidt-Cassegrain telescope. Credit: BBC Sky at Night Magazine

Single arm Go-To alt-azimuth mount

The single arm mount is well made, solid and fits neatly into the tripod base, being held in place by a large plastic knob. The mount has a Vixen-style saddle for attaching the telescope, with a good chunky retaining bolt giving a solid grip to the scope.


The simple but effective tripod has aluminium telescopic legs that can be extended to give a range between 86cm and 137cm. The mount attaches easily with a single underside bolt from the tripod which holds it firmly in place. The spreader tray can hold two 1.25-inch eyepieces and there is an integrated rubberised smartphone holder.


The Astro Fi 6 SCT comprises a primary mirror and a corrector plate (with the secondary mirror attached to the corrector) and StarBright XLT coatings for improved light transmission. It has a ‘long’ focal length of 1,500mm, giving a focal ratio of f/10, making it ideal for both planetary and deep-sky viewing.


The StarPointer red dot finder is useful for the initial alignment. Two eyepieces are provided, 25mm and 10mm, giving magnifications of 60x and 150x, along with a 90° star diagonal. A useful extra is the basic but functional smartphone holder, adding a new dimension to the setup.

Ports and Wi-Fi

The mount incorporates two aux ports; one can be used for an optional hand controller and the other is spare. Above them lies the integrated Wi-Fi for connecting to the SkyPortal app. At the front is an on/off switch and a 12V DC power connector is provided.

Vital stats

Price £649

Optics 150mm (6-inch) SCT compound telescope with StarBright XLT coatings

Focal length 1,500mm, f/10

Mount Wi-Fi computerised altazimuth single fork arm

Ports Power connector, two aux ports, integrated Wi-Fi adaptor, on/off switch

Tracking rates Sidereal, lunar and solar

Tripod Adjustable with accessory tray, including smartphone holder

Extras StarPointer red dot finder, 25mm and 10mm 1.25 inch eyepieces and star diagonal, battery pouch

Weight 6.71kg

Supplier David Hinds Limited

Tel 01525 852696