How to Photograph The Moon with a Telescope

The Moon is undoubtedly the easiest celestial object to photograph owing to its brightness and huge angular size. In the early days of plate camera photography, it took decades for decent photographs of the Moon to be achieved; early lunar imaging was comparable in difficulty to deep-sky astrophotography due to the low sensitivity of daguerreotype and collodion cameras, which required exposures of at least several minutes, and it wasn’t until the 1870s that decent results were achieved. Today, you can hold your smartphone up to the eyepiece of any telescope and take photos that would have blown away someone back then.

Cameras for Lunar Photography

Imaging the Moon can be done quite well with three types of cameras: your smartphone, a DSLR/mirrorless camera, or a CCD/CMOS video camera. All have advantages and disadvantages, as well as requiring different hardware to attach to your telescope. We recommend at least trying smartphone photography before getting into other types of cameras, since odds are that you already have a decent smartphone camera and suitable eyepieces for your telescope.

Smartphone lunar photography is undoubtedly the easiest method. You can get decent single shots with your phone held up to the eyepiece. Getting an adapter like the Celestron NeXYZ adapter can help you get better pictures. It will let you carefully centre your phone on an eyepiece for less aberrations and vignetting, and it will usually let you use a higher magnification than you could with a hand-held smartphone camera. A remote shutter release further improves the situation. In most cases, the best images are taken with an eyepiece providing an exit pupil of around 1-2 mm, or 12–25x magnification per inch of telescope aperture. Smaller and you’ll get vignetting; larger and you might get more of the Moon at once or have an easier time centering things, but you lose resolution.

It’s even possible to take video and stack it in the manner of a planetary camera, though the decrease in resolution of video mode with some phone cameras may ruin any advantage in doing so. Taking burst shots and then stacking them like video frames is sort of a middle ground between single shots and video and tends to be the best way to get sharp images with your smartphone if you are willing to put in the effort.

Besides the inconveniences of extracting the files from your phone (particularly if you are using an iPhone, where it is extremely difficult to transfer the images/video over a physical USB connection), the biggest issue of smartphone photography is that the number of optics involved needlessly degrades the image. Your eyepiece adds aberrations of its own, as does the lens of your phone camera. This, combined with the limited frame rate and resolution compared to a dedicated camera, means that smartphone photography is not nearly as capable as a true planetary camera. However, you can still get great results with remarkably little equipment, time, or effort.

DSLR and mirrorless cameras used to outclass smartphones for lunar and planetary imaging and allow you to put the camera directly in prime focus. This is a relatively simple affair – though most cameras will require you to use a Barlow lens to get the image to focus, which also improves the image scale anyway. However, the large pixels of these cameras limit your resolution, and shooting video may result in even worse under-sampling to the point that a smartphone/eyepiece might produce sharper photos.

Lastly, the third and most capable option for lunar imaging is a dedicated CMOS camera like the ZWO ASI224MC. You can shoot at over 60 FPS to take high-resolution videos and then stack them in a program like RegiStax or AutoStakkert to compensate for atmospheric seeing and noise, then do post-processing in any program you wish to use. A Barlow lens can be used to increase the focal length and image scale up to the limits of your telescope’s resolving power, but it will require you to take several videos of different areas of the Moon and combine them into a mosaic if you want to image its whole disk at once.

We highly recommend taking videos with at least 2,000-3,000 frames on your smartphone or with a planetary camera and then stacking them with AutoStakkert for the best possible images. AutoStakkert will allow for the best possible alignment between frames, and if you’re shooting only a small area of the Moon, it can create a “mosaic” of all of the area you capture in all of the frames if your telescope slightly drifts around during the length of the capture. Registax will just crop it.

It’s important when processing your photos of the moon to make sure to remove any residual colour (or simply shoot in black and white) and remember to set the black point correctly. There are no grey shadows on the moon. Dark craters and shadows behind mountains should be jet-black, period. Likewise, you should make sure that lighter features such as the Moon’s limb or crater rays are not blown out when shooting and processing.

Imaging Lunar Eclipses

Total solar eclipses are covered in our separate article and require additional precautions and gear to image or observe. However, lunar eclipses can be photographed with the same gear as the Moon can normally, but with key differences in settings as well as general limitations.

Lunar eclipses during the partial phase create the problem of an extreme brightness difference; the eclipsed part of the Moon is thousands of times dimmer than the remaining sunlit area. Even during the total phase, in some instances, the brighter areas may completely blow out your sensor if you optimise the exposure/gain for the eclipsed part. Thus, you will probably need to take multiple shots of the Moon at different exposure/gain settings and combine them for a high dynamic range, or “HDR” composite shot. 

It should also be noted that the dimness of the Moon may create a lot of noise if you try to image it with a smartphone, and you may have to use a DSLR to get a shot of the full disk despite its normally sub-optimal resolution characteristics. The best shots are often those of the eclipsed Moon with a DSLR/mirrorless camera and short focal length telescope or camera lens, showing the eclipsed Moon and normally-invisible stars around it in the background.

An amateur astronomer and telescope maker from Connecticut who has been featured on TIME Magazine, National Geographic, Sky & Telescope, La Vanguardia, and The Guardian.

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