There's a total lunar eclipse to photograph on May 26–get prepared to photograph it with our ultimate guide
Have you ever seen a ‘Blood Moon’? The colloquial term for a total lunar eclipse, it’s something that’s visible from most places on Earth every few years. Totally safe to observe with the naked eye and to photograph, it’s a slow-burning celestial spectacle that most people wait to come to them, though at its peak it’s a dramatic sight as a full Moon shines red, orange and pink. It’s typically the highlight of the astronomical calendar.
A total lunar eclipse will next occur on 26 May, 2021 when a ‘supermoon’ will be visible from the entire night-side of Earth. In this case, that means Australia, parts of the western US, western South America and South-East Asia.
A total lunar eclipse occurs during a full Moon when the Earth is in between the Sun and the Moon. During the event, May’s ‘Flower Moon’ will transit through Earth’s shadow in space, something it does only occasionally. Its surface will turn a reddish-copper colour because all of the light on the Moon will have been filtered by Earth’s atmosphere. The physics is a bit like a sunset, and the effect is an eery sight indeed.
On 26 May, 2021 the ‘totality’ phase – during which the Moon turns its reddest – will only last for 14 minutes, giving photographers a narrow window. It will be visible in the west to everyone in the western states of the US (this Google Map shows you exactly where) in the early hours of 26 May, 2021 (11:11-11:25 UTC/04:11-04:25 a.m PST).
A ‘Blood Moon’ is much easier and safer to photograph than a solar eclipse, but there won’t be much time to get the shot. So here are some of our top tips so you can get prepared and ready for the ‘Super Flower Blood Moon’ total lunar eclipse…
1 Understanding the different phases of a ‘Blood Moon’
Although it may seem like a simple event there are several drastically different phases of the event that you need to know about in advance. Earth has two shadows; it’s outer, fuzzier penumbral shadow and its deeper, darker and more defined inner umbral shadow. So there will be a period of a penumbral lunar eclipse, during which the full Moon’s light dims, followed by a partial lunar eclipse as it begins to pass into the umbral shadow.
Once the whole of the Moon is within Earth’s penumbral shadow it is totality – and the moment the Moon turns reddish. Although totality is what everyone wants to see, the partial phases are also interesting and a good time to practice your technique.
In practice, eclipse-chasing is cloud-dodging because without clear skies you’ll see nothing. So have a few locations in mind beforehand and be prepared to travel according to where there are clear skies. Check and re-check local weather reports and change your plans accordingly.
2 What photography gear you’ll need
To successfully photograph the Moon up close you’ll need a DSLR or mirrorless camera that allows full manual control of all settings. Use a sturdy tripod. You’ll need a telephoto lens with a focal length of a minimum of 300mm, but preferably over 600m. Consider using a teleconverter to extend the effective focal length of the longest lens you have.
A shutter release cable will let you take photos without introducing vibrations. If you don’t have one then look for a self-timer or shutter delay mode on your camera so that it opens the shutter a few seconds after you’ve pressed the shutter button. The longer your lens is, the more critical it will be to have zero vibrations in the camera.
If you have access to a telescope you may be able to hook-up your camera using a T-adaptor, which are specific to brands and models of camera. It can be much more economical than purchasing a giant telephoto lens. However, the focal length of the telescope will affect your exact view, so do experiments with the Moon before eclipse night.
If your telescope is a ‘go to’ computerised product or has an equatorial mount it will track the eclipsed Moon, which can be very helpful.
3 Imaging the penumbral and partial lunar eclipse phases
The eclipse will begin with a penumbral phase, during which the full Moon will begin to dull. In itself, it’s not exactly an exciting shot, but this period – which on 26 May 2021 will last about an hour – is one of the easiest times to photograph the Moon. As a guide, you’ll need a lens at about f/4 and then set your camera to ISO 100 and a shutter speed of about 1/500 seconds, though as the Moon enters more of the Earth’s shadow you’ll have to up the ISO and increase the shutter speed.
Once the Moon begins to enter the Earth’s umbra you’ll see an almost straight line on the lunar surface that divides a darker, browny-orange side of the Moon from a brighter grey side. That’s the curve of Earth!
On 26 May 2021 this partial phase will last about 85 minutes and end with totality. In clear skies, you can use the initial stages of the penumbral, then partial, eclipses of the Moon to practice your technique in advance of totality.
Always shoot in the RAW format. Don’t rely only on compressed JPEG photos and don’t always believe what you’re seeing on your camera’s rear-view screen. By conserving as much data as possible as RAW images you’ll be able to use photo editing software after the event to tease out more detail and suppress noise.
4 Capturing a ‘Blood Moon’ during totality
While not technically challenging, photographing a total lunar eclipse does require some quick-thinking. The light on the Moon’s surface is reduced, but constantly changing during totality, and on May 26, 2021, it’s going be super-quick. In fact, it’s so quick that the lunar surface may only reach a subtle peach or copper colour. It’s impossible to know in advance.
During totality you’re likely going to need to work between ISO 200 and ISO 800 (though full-frame cameras can probably cope with up to around ISO 3200) and use the widest aperture your lens is capable of to cope with a darkened lunar surface. Shutter speeds will depend on your lens and its aperture, but you can calculate them in advance using the Lunar Eclipse Exposure Guide. Consider using the bracketing technique, which is the taking of three shots using different shutter speeds.
The key to taking close-ups of the Moon is retaining sharpness. A shutter speed of 1/100 will help you avoid blur, which may mean using a high ISO, but experiment; a slightly blurry ‘Blood Moon’ is better than none at all. And remember that even during the short totality you’ll need to make adjustments to keep the eclipsed Moon in your frame.
5 How to take wide-field shots of the ‘Blood Moon’ among the stars
Although taking a close-up shot of a ‘Blood Moon’ is an exciting moment, it’s not going to be a unique photo. Search social media and you’ll find millions of near-identical shots from previous eclipses.
If you want something unique go for a wide-angle shot of the ‘Blood Moon’ in a landscape with an original foreground. To capture that you’ll need a lens with a much wider focal length. With the lens set to its widest aperture (such as f/2.4), start at ISO 400 for totality and play with shutter speeds up to 30 seconds.
Although the Moon will feature only as a small object, you’ll capture it in a unique context. If you head to a dark sky site you’ll also have the chance to capture stars around a reddish Moon because during totality the moonlight is dimmed enough for the stars, and even the Milky Way, to become more easily visible to the naked eye.
If you want to plan a specific shot consider using apps like The Photographer's Ephemeris (TPE) and PhotoPills so you can see exactly where the eclipsed Moon will be at all stages of the eclipse. However, it’s better to fixate on finding clear weather that on a particular pre-planned shot.