How to Photograph a Lunar Eclipse (Blood Moon)

To photograph a lunar eclipse, use a tripod, manual exposure and manual focus, and change the exposure as the moon darkens. The full moon is sunlit, so start near f/11, 1/125 second, ISO 100. The totally eclipsed red moon is usually 12 to 14 stops dimmer: start near f/5.6, 1 second, ISO 1600 and bracket widely, because every eclipse has a different brightness. No filter or eye protection is needed.

How to photograph the moon covers ordinary lunar photography: lenses, focus and exposure by phase. This guide goes further into the one night when all of that changes minute by minute: the exposure for each stage of an eclipse, how to keep a dim moon sharp while it drifts, how to shoot a sequence, and how to edit the red colour truthfully. For the sun, which needs certified filters and a very different plan, see how to photograph a solar eclipse.

What happens during a lunar eclipse, and why exposure swings so far

A lunar eclipse happens at full moon, when the Earth sits directly between the sun and the moon and the moon passes through the Earth’s shadow. The shadow has two parts. The penumbra is the pale outer zone where the Earth blocks only part of the sun. The umbra is the dark core where it blocks all direct sunlight. The stages follow in a fixed order:

1. Penumbral phase. The moon enters the outer shadow. For most of this stage nothing seems to change; near the end, one side looks slightly dusky.
2. Partial phase. The umbra takes a curved, dark bite out of the disc, growing over about an hour.
3. Totality. The whole moon is inside the umbra and glows red, orange or brown. This can last from a few minutes to well over an hour.
4. The same stages in reverse as the moon leaves the shadow.

The moon does not go black in totality because the Earth’s atmosphere bends some sunlight into the shadow. That light has passed through a long path of air, which scatters away most of the blue and leaves red, exactly as it does at sunset. In effect the moon is lit by every sunrise and sunset on Earth at once. How bright and what colour it appears depends on how deep the moon passes into the umbra and how much cloud and dust is in the Earth’s atmosphere that day, so no two eclipses are alike.

For the camera the consequence is simple. The uneclipsed moon is a sunlit rock that needs a daylight exposure. The moon in totality is commonly ten thousand times dimmer. No single setting covers both, and automatic exposure is fooled at every stage by the black sky around the moon. You have to drive the exposure yourself.

Planning: timing, moon position and foreground

Unlike a solar eclipse, a lunar eclipse is visible from the whole night side of the Earth at the same moments, so there is no narrow path to travel to. What you need from an astronomy calendar or planning app is a short list for your location:

• The local times at which the partial phase begins, totality begins, totality ends and the partial phase ends.
• The moon’s height and compass direction at each of those times. A full moon is opposite the sun, so it rises around sunset, is highest around the middle of the night and sets around sunrise.
• Whether the moon is up for all of it. If it rises or sets during the eclipse you will lose some stages, but you gain the chance of an eclipsed moon near the horizon with a landscape.

The method for reading moon position and timing is in planning around the sun, moon and tides. Then choose a site with an open view in the right direction. City light matters much less than for stars, because the subject is bright enough to punch through skyglow, although a dark site gives a blacker sky and shows the stars that appear around the moon in totality.

Prepare for a long, cold stand: a full eclipse from first bite to last takes three hours or more. Charge two batteries, clear a card, and decide in advance which pictures you want (close-ups, a landscape, a sequence), because there is little time to improvise once totality starts.

Focal length: a close-up moon or an eclipse in a landscape

The moon is about half a degree across. On the sensor, its diameter in millimetres is roughly the focal length divided by 110, so it is small in almost any lens:

A crop-sensor camera gives a tighter view from the same lens (see crop factor), which helps here. So does a teleconverter for the bright stages, although the light it costs hurts in totality.

There are two different pictures to choose between, and they need different lenses.

The close-up uses the longest telephoto lens you have, 300mm or more, and shows the curved shadow edge and the colour of totality. Its difficulty is sharpness, covered below.

The eclipse in a landscape uses a wide to short telephoto lens and treats the red moon as one element of a scene. It is easiest when the eclipsed moon is low. A moon high overhead is hard to connect with anything on the ground unless you use a very wide lens, in which case it becomes a small dot. In totality the moon is dim enough that the moon, the stars and a dark foreground can sometimes be recorded in a single exposure of a few seconds, which is never possible at a normal full moon.

Exposure phase by phase, from full moon to totality

The starting point for the uneclipsed moon is the lunar version of the Sunny 16 rule: f/11 at a shutter speed of one over the ISO, so about 1/125 second at ISO 100. At f/5.6, two stops wider, that is 1/500 second. The table uses f/5.6 throughout so the numbers can be compared. If your lens is f/8, double every shutter time; at f/4, halve it.

From a full moon to a typical totality is a change of roughly 12 to 14 stops. A bright eclipse may be only 10 or 11 stops down, and a very dark one 16 or more. Nobody can tell you in advance which you will get, so treat the totality rows as the middle of a search, not an answer.

How to work through the night

• Shoot raw in manual mode and judge each stage on the magnified image and the histogram, not on the brightness of the rear screen, which looks far brighter in the dark than the file really is.
• During the partial phase, expose for the bright part. Keep the sunlit sliver from clipping. The shadowed part will be black in these frames, and that is correct.
• As the sliver shrinks, add exposure in steps. Lengthen the shutter time first, then raise the ISO once the shutter time reaches the sharpness limit in the next section.
• Near the start and end of totality, shoot both versions: one exposure for the last bright edge and one several stops longer for the red disc.
• In totality, bracket. Shoot a run of five frames one stop apart around your best guess, look at the middle one, and shift the whole run if needed. Bracketing explains the automatic modes; manual changes of shutter time work just as well.
• Recheck during totality. The moon is dimmest at mid-eclipse and the side nearer the edge of the umbra stays brighter, so the best exposure changes while you watch.

Keeping the moon sharp when exposures get long

A bright moon allows 1/500 second and sharpness is easy. Totality asks for exposures near a second through a long lens, and three things then soften the picture.

The moon is moving. The turning Earth carries it across the sky by its own diameter about every two minutes. On a fixed tripod the image slides across the sensor at roughly 7 thousandths of a millimetre per second for every 100mm of focal length. That gives two practical limits:

These apply to the lens’s real focal length, and a higher resolution or smaller sensor shows the blur sooner. When the exposure you need is longer than the limit, open the aperture fully and raise the ISO to 3200 or 6400 before you let the shutter run long. A noisy sharp frame can be cleaned up; a smeared one cannot. A shorter lens is the other honest answer: 200mm at 1 second often beats 600mm at 1 second.

A star tracker removes most of this limit. Running at the normal star rate it follows the sky closely enough for exposures of several seconds at 400mm, since the moon drifts against the stars by only its own diameter in about an hour.

The camera is shaking. Use a solid tripod with the lens supported at its collar (see using a tripod with a big zoom lens), a remote release or a 2 second delay, and mirror lock-up or an electronic first curtain if your camera has one. Switch stabilisation off on the tripod unless the maker says otherwise.

Focus has drifted or was never set. Focus before the eclipse starts, on the edge of the bright moon in magnified live view, then switch to manual focus and tape the ring. Autofocus often fails on the dim, low-contrast disc of totality. If you must refocus then, use a bright star.

Finally, reframe often. On a fixed tripod at 400mm the moon crosses the whole long side of a full-frame sensor in about twenty minutes.

Shooting a sequence and assembling a composite

A row or arc of moons showing the whole eclipse is the classic result. There are two ways to make one, and they are different kinds of picture.

A true sequence on one fixed frame

Lock a wide lens on a tripod and never move it. The moon travels about 15 degrees an hour, so a three and a half hour eclipse covers roughly 50 degrees of sky. A 24mm lens on full frame sees about 74 by 53 degrees, which is enough if you aim it carefully. Work out with an app where the moon will be at the first and last moments and frame so both fit, with the foreground at the bottom.

1. Shoot one frame at a fixed spacing of 5 or 10 minutes. The moon moves its own width in two minutes, so 5 minutes leaves a clear gap between discs.
2. Change the exposure for each stage using the table above. An intervalometer can time the frames, but you still set each exposure by hand.
3. During totality or twilight, take one longer exposure for the foreground and stars.
4. In an editor, stack the frames as layers over the foreground frame and set the moon layers to the Lighten blend mode so each disc appears in its true position.

Every moon in this picture is where it actually was. The discs are small, about 1 percent of the frame height at 24mm.

An arranged sequence of close-ups

Shoot telephoto close-ups at regular intervals and later place them side by side on a black canvas. This shows the shadow’s progress in detail, and it is a designed graphic, not a view anyone saw. Keep the scale and orientation of every disc the same, keep the order true, and say in the caption that it is a composite. The same applies if you paste a large telephoto moon into a wide landscape: describe it as a composite, and do not enlarge the moon beyond what the lens recorded if you want to present the picture as a record of the event. Photography ethics covers where those lines sit.

Photographing a lunar eclipse with a phone

A phone can record the event, though not a detailed close-up. The lens is wide, so the moon is tiny, and automatic exposure burns the bright stages to a white blob.

• Fix the phone to a tripod and use the longest optical lens it has. Avoid heavy digital zoom, which only enlarges blur.
• For the partial phase, tap the moon to set focus and exposure, then drag the exposure control down until the shadow edge and surface markings appear.
• For totality, use night mode or a manual app with a shutter time of 1 to 4 seconds. Expect a small, soft, red disc.
• Go for the scene. A phone does best with the red moon above a skyline, trees or people watching.
• Borrow some magnification. Holding the phone’s lens to the eyepiece of binoculars or a small telescope on a steady mount gives a far larger moon than any phone zoom.

Night photography with a smartphone has the general low-light method.

Editing the red moon without overcooking it

Start with white balance. Set it to daylight, around 5200K, for every frame of the eclipse. The moon is lit by sunlight throughout, and the red of totality is a real colour, not a cast. Automatic white balance tries to neutralise it and turns the moon a muddy tan. This is one more reason to shoot raw, as raw versus JPEG explains.

• Set brightness by memory, not by the histogram. In totality the moon looked dim. A totality frame pushed up to full-moon brightness looks false.
• Go easy on saturation. The colour is usually a soft copper, rust or brick red. If the red channel clips, the disc turns into a flat orange circle with no surface markings. Add contrast first and see whether saturation is needed at all.
• Keep the gradient. One side of the totally eclipsed moon is normally brighter and yellower than the other. Sometimes a thin blue or turquoise band shows along the edge of the shadow, produced by light that has passed through the ozone layer. Both are real, so do not even them out.
• Reduce noise before sharpening. Totality frames are high-ISO files with soft detail, and strong sharpening mostly sharpens noise.
• Blended partial phases need a label. Combining a short exposure for the bright sliver with a long one for the red shadow (see exposure blending) shows more than a single frame or the eye could. It is a legitimate technique. Say you used it.

Common mistakes

• Leaving the camera on automatic. The meter sees a black frame and overexposes the moon to white. Fix: manual mode at every stage.
• Keeping the full-moon exposure into totality. The frames are black. Fix: add exposure step by step as the sliver shrinks, to around a second at f/5.6 and ISO 1600.
• Long exposures at long focal lengths. A 4 second frame at 400mm is a smear. Fix: stay near the limits in the table, and raise ISO or open the aperture instead.
• One exposure in totality. If the guess is wrong there is no second chance. Fix: bracket five frames a stop apart, more than once.
• Refocusing in totality. Autofocus hunts on the dim disc. Fix: focus on the bright moon beforehand and tape the ring.
• Losing the moon out of frame. It drifts its own width every two minutes. Fix: reframe every few minutes on a fixed tripod.
• Automatic white balance. The red goes brown. Fix: daylight white balance.

Try this

Rehearse on any clear night with a bright moon. It takes about 15 minutes and answers the two questions that matter before an eclipse.

1. Set up your longest lens on a tripod. Focus on the moon’s edge in magnified live view and tape the ring.
2. In manual mode, shoot the moon at f/11, 1/125 second, ISO 100. Then try one stop either side. Note which gives the best surface detail from your location.
3. Time the drift: centre the moon, start a timer and see how long it takes to reach the edge of the frame. That is how often you must reframe.
4. Now test the totality problem. Point at a bright star near the moon, set f/5.6 (or your widest aperture) and ISO 1600, and shoot at 1/4, 1/2, 1, 2 and 4 seconds.
5. Magnify each frame. Find the longest time at which the star is still a point and not a dash. That is your real shutter limit at this focal length, on this tripod.

Frequently asked questions

What camera settings should I use for a blood moon?

For the red moon in totality, start at your widest aperture (f/4 to f/5.6), ISO 1600 and about 1 second, then bracket from 1/4 second to 4 seconds. Brightness differs from one eclipse to the next, so check the image and adjust.

Do I need a filter or eye protection for a lunar eclipse?

No. A lunar eclipse is no brighter than an ordinary full moon and is safe to look at and photograph with any lens, binoculars or telescope. Only solar eclipses need certified solar filters.

What lens do I need to photograph a lunar eclipse?

For a close-up, 300mm or longer, with 400mm to 600mm giving good detail. For a landscape or a sequence across the sky, anything from 24mm to 100mm works, with the moon as a small part of the scene.

Why is my eclipsed moon blurry?

Usually because the shutter time was too long for the focal length and the moon moved during the exposure. Other causes are tripod shake, focus that was set by autofocus on the dim disc, and unsteady air when the moon is low.

How long does a total lunar eclipse last?

The partial phases take about an hour each, and totality lasts from a few minutes to about an hour and three quarters, depending on how centrally the moon crosses the shadow. Allow three to four hours for the whole event.

Related guides

• How to photograph the moon: lenses, focus and exposure for every ordinary phase.
• How to photograph a solar eclipse: filters, safety and the stages of the other kind of eclipse.
• The Sunny 16 rule: where the f/11 moon exposure comes from.
• Planning around the sun, moon and tides: finding where the moon will be at each stage.
• How to photograph a meteor shower: another night-sky event that rewards a rehearsed plan.
• Astrophotography for beginners: trackers, stacking and the wider night sky.
• Bracketing: setting up a run of exposures quickly.