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Published: Sunday, 21 July 2024 at 07:33 AM


Have you ever been observing the night sky through your telescope and wondered whether you could photograph what you see with your smartphone camera?

In this guide we’ll look at smartphone telescope astrophotography and reveal some of the best ways to achieve this, plus the best targets to aim for.

First, let’s look at the logistics of using a smartphone-telescope combo to photograph the night sky.

Find out more in our guide to smartphone astrophotography

Pointing your smartphone through your telescope eyepiece

Afocal imaging

Afocal imaging is the technique of manually pointing your smartphone camera through your telescope eyepiece, and can be tricky to get right. Credit: Cavan Images / Getty Images

One of the simplest ways to do smartphone astrophotography through a telescope is to use the afocal technique, where a picture is taken while the camera is held up to the eyepiece.

Improvements in mobile phone camera technology and apps that allow manual camera settings mean that it’s now possible for phones to capture really good astro photos at the eyepiece. 

The advantage of the afocal technique is that it can be done with any telescope used for visual observing.

Pointing smartphone camera down telescope afocal imaging

You don’t need to remove the eyepiece to take a photo, so it’s very easy to switch between visual observing and imaging.

The camera’s zoom function also allows you to digitally increase the magnification through the same eyepiece.  

Although you can manually hold the phone up to the eyepiece, trying to keep the camera lens perfectly lined up with the light cone of the eyepiece while also adjusting the telescope/focuser and navigating the camera settings is much more difficult than it sounds!

Smartphone adaptor

Altair Astro Self-Centering Smartphone Telescope Adaptor. Credit: Altair Astro
Credit: Altair Astro

The easiest solution to lining up your smartphone’s camera with your telecope eyepiece is to buy a smartphone telescope adaptor.

This clips on around the telescope eyepiece and holds the phone firmly in the correct position, leaving your hands free to concentrate on adjusting the focus and camera settings. 

There are many smartphone telescope adaptors available that will keep the camera lens perfectly lined up with the eyepiece.

When choosing one, check that it will fit the eyepiece you’re using, as not all adaptors expand far enough to fit around eyepieces larger than 1.25 inches in diameter.

When you first set up the adaptor for your phone, make sure you’re lined up with the correct lens, because most modern phones have multiple camera lenses and may suddenly switch between them as you zoom in and out.

telescope smartphone holder

Photographing with your smartphone-telescope combo

Once your smartphone is attached to your telescope eyepiece, the most important step is gaining manual control of the camera so you can do real astrophotography

You need to be able to focus the telescope and not have the phone constantly auto-adjusting focus, exposure and ISO.

In low light, the camera will probably get the focus wrong and either over- or underexpose images to cope with the dynamic range.

Fortunately, native camera apps often have additional controls hidden in the ‘Pro’ menus that allow you to manually adjust focus, exposure and ISO settings. 

The Moon Sonia Turkington, North Reddish, Stockport, 25 June 2023 Equipment: Google Pixel 6 smartphone, Sky-Watcher Classic 250P Dobsonian reflector, integrated mount
The Moon Sonia Turkington, North Reddish, Stockport, 25 June 2023 Equipment: Google Pixel 6 smartphone, Sky-Watcher Classic 250P Dobsonian reflector, integrated mount

Shorter exposures work well on bright objects like the brighter planets, the Moon and the Sun (with the addition of a solar filter or Herschel solar wedge) and so these targets are a good place to start when finding your way around the camera settings.

You can then try more challenging, fainter deep-sky objects which may require longer exposures than the native camera app can provide.

M13 taken with NightCap. Stars mode, 30.05 second exposure, 1/3s shutter speed. Credit: Paul Money
M13 taken with NightCap. Stars mode, 30.05 second exposure, 1/3s shutter speed. Credit: Paul Money

There’s an app for that

If the camera is compatible, apps like NightCap or AstroShader (iPhone) and Open Camera or DeepSkyCamera Beta (Android) will allow longer exposures and better settings control, and they can capture at the highest resolution. 

Some apps provide live stacking, others can capture a sequence of images, darks and flats which you can manually stack to improve results for fainter objects.

Remember that your maximum exposure time is governed by whether or not your telescope mount is static or tracking.

Deep-sky objects often don’t show up so well on screen, so like all astrophotography it takes practice to really perfect the technique for these challenging objects.

You can improve your images with some basic image processing too.

Sunspots, taken with the Bresser ISA Space Exploration NASA 70/700 AZ telescope on an iPhone 5s using the solar filter, 20mm eyepiece and smartphone adaptor. Credit: Steve Richards
Sunspots, taken with the Bresser ISA Space Exploration NASA 70/700 AZ telescope on an iPhone 5s using the solar filter, 20mm eyepiece and smartphone adaptor. Credit: Steve Richards

Best targets for your smartphone-telescope combo

There are a dazzling number of night-sky objects that make great targets for smartphone astrophotography, but you’ll get the best results if you choose ones that suit the type and aperture of your telescope.

Different objects need different ISO and exposure times, so keep checking your live view to refine your settings.

Stacking multiple images will reveal more faint details.

Small telescopes

The Moon is a great place to start astrophotography with a smartphone and telescope. Fairphone 4 on a 70mm refractor. Credit: Mary McIntyre
The Moon is a great place to start astrophotography with a smartphone and telescope. Fairphone 4 on a 70mm refractor. Credit: Mary McIntyre

Large, bright objects are better suited to smaller-aperture telescopes.

The Moon and Sun (with a certified solar filter/Herschel solar wedge) are a great place to start, because they’re easy to see on the screen.

The Beehive Cluster. Fairphone 4 on a 70mm refractor. Credit: Mary McIntyre
The Beehive Cluster. Fairphone 4 on a 70mm refractor. Credit: Mary McIntyre

You can use your digital zoom to magnify further, but be aware that some images get very grainy at full zoom.

Big open clusters, such as the Double Cluster, the Beehive Cluster, M44, and the Pleiades, M45, are good choices, as are brighter nebulae such as the Orion Nebula, M42, or brighter galaxies such as the Andromeda Galaxy, M31.

A superb Lagoon Nebula. Samsung S22 Ultra, ED80 with 24mm TeleVue and L-eNhance filter. ISO 3200, 410x 55”. Credit: @astropunk
A superb Lagoon Nebula. Samsung S22 Ultra, ED80 with 24mm TeleVue and L-eNhance filter. ISO 3200, 410x 55”. Credit: @astropunk

You can also photograph Jupiter and its Galilean moons, although you probably won’t see surface detail on Jupiter.

Medium and large telescopes

Close-up of craters with a Fairphone 4 on a budget 102mm refractor. Credit: Mary McIntyre
Close-up of craters with a Fairphone 4 on a budget 102mm refractor. Credit: Mary McIntyre

Larger-aperture telescopes allow closer photographs of lunar craters, lunar mountains and sunspots, and more detail on the larger planets Jupiter, Saturn and Mars

Smaller and fainter open clusters, globular clusters, galaxies and comets can be captured.

Even planets are feasible. Saturn with a Google Pixel 6 and 10-inch Dobsonian. Credit: Sonia Turkington
Even planets are feasible. Saturn with a Google Pixel 6 and 10-inch Dobsonian. Credit: Sonia Turkington

Experiment with eyepiece filters that enhance objects with low surface brightness.

The additional resolving power of larger apertures will also allow photos of double stars.

Andromeda Galaxy with an iPhone 13 on a Sky-Watcher Skyliner 250P Dobsonian. Credit: Jon Adams
Andromeda Galaxy with an iPhone 13 on a Sky-Watcher Skyliner 250P Dobsonian. Credit: Jon Adams

We regularly showcase readers’ images in the magazine and online. Whether you’re a beginner or experienced astro-imager, send us your images – we’d love to see them.