With the total lunar eclipse taking place on January 31 of 2018, you might want to experience watching and potentially photographing this rare and stunningly beautiful phenomenon. I previously had a chance to photograph both partial and total lunar eclipses, so I was able to document my experience and provide information on what challenges I had during the process. In this article, I will do my best to explain how to photograph a lunar eclipse in detail.
1) Basics of Moon Photography
Before reading the information below, I highly recommend reading my “how to photograph the moon” article, where you can find plenty of information (including camera settings) on how to photograph the moon. You will need that while capturing the beginning and the end of the eclipse, when the moon is partially lit by the sun.
2) Photographing the Sequence
One thing you need to decide on, is whether you want to shoot the entire sequence of the lunar eclipse, or just the middle of the process (period of totality) when the moon is orange/red in color. I would personally recommend to document the whole process from the beginning to the end, so that you have pictures of the full moon, then a partial eclipse, then a total eclipse, then a partial eclipse again, returning back to full moon when the eclipse ends. The nice thing about having the entire sequence in pictures, is that you can later combine images together like this:
You will have to be very patient though – it took me about four hours in total to capture the moon from the beginning to the end of the eclipse. The night was very cold (below freezing) where I live and although I wore very warm clothes, I had to run home back and forth to get warmer. Thankfully, I did everything right outside of my home and did not have to drive anywhere far. There was plenty of light pollution in the sky, but it did not seem to impact my images as much, so you can certainly do it from right where you live too.
If for whatever reason you cannot stay for the entire duration of the eclipse, I would just stay for the total eclipse to capture the moon when it is red.
3) Camera Equipment and Lenses
When it comes to photographing a lunar eclipse, the type of equipment you are using plays a huge role. Photographing a lunar eclipse is not the same as photographing the moon for one major reason – lack of light. When you photograph the moon while it is lit by the sun, it is typically so bright, that you can easily use fast shutter speeds at very low camera ISO, without having to worry about noise. Photographing a lunar eclipse is much more challenging, because the moon gets very dim when it is in the Earth’s shadow. Not only will you have to decrease your shutter speed, but you will also have to increase camera ISO to a much larger value, especially if you are shooting with long lenses above 300mm. Having a good DSLR or a mirrorless camera that can handle noise at high ISO levels will certainly help.
When it comes to lenses, longer lenses will magnify the moon more and provide some good details for your shots. So, unless you are planning to capture the moon with a large foreground element, I would recommend to use the longest lens in your arsenal. But a longer lens presents another problem for moon photography – you will have to use a fast shutter speed to get blur-free images of the moon, since it moves so fast (see below).
4) Camera Settings
When you shoot a bright moon, a good exposure is typically around 1/125-1/250th of a second @ f/11, ISO 100-200. When an eclipse starts, this exposure will work great to expose the bright part of the moon, while the dark side of the moon is not going to be visible at all. At some point, you will have to change your exposure to expose for the dark side, while overexposing the bright side of the moon, similar to this image:
I found out that the exposure difference between the bright and the dark sides was a whopping 8 full stops! What does this mean? It means that if you were getting a great exposure of the sun-lit moon at 1/250th of a second at ISO 200, in order to capture the part of the moon that is in earth’s shadow, you would have to shoot at 1 second @ ISO 200 (1/125 -> 1/60 -> 1/30 -> 1/15 -> 1/8 -> 1/4 -> 1/2 -> 1)!
This is the part where the focal length of your lens becomes your enemy. The longer the lens, the more you need to worry about two major problems – shutter speed and camera shake. A long lens (above 300mm) will make the moon larger in your picture, which at the same time means that the moon will move very quickly through your frame. Using a slow shutter speed is obviously unacceptable, because the moon features will all appear blurry. Therefore, your only choice (aside from getting a motorized equatorial mount) is to shoot at maximum aperture and increase camera ISO to a large number. In the above example, to increase my shutter speed to just 1/15th of a second, I would have to shoot at ISO 3200, which would result in a lot of grain, especially if I were shooting on a DX camera. So, what should your shutter speed be? It depends on the focal length of your lens. If you are shooting at 300mm on a DX body using a lens like the Nikon 70-300mm VR, shoot at shutter speeds faster than 2 seconds. If you are using a longer lens, you will have to use even faster shutter speeds to get a blur-free image of the moon. I was shooting at 560mm (Nikon 200-400mm @ 400mm + 1.4x TC) on a full-frame body (Nikon D3s) and I found that my limit was about a half a second (1/2) before the moon started to get blurry.
Take a look at the below crop shot at 2 seconds to see how blurry the moon got:
And that’s with me shooting on a tripod using a remote shutter release, plus Mirror Lock-Up with about 1 second interval after raising the mirror! Let’s talk about camera shake for a second. Whenever you shoot with long lenses over 300mm, you have to make sure that you have a very stable setup. It goes without saying that your camera needs to be mounted securely on your tripod and you should not be pressing the shutter with your hand. Either use a remote shutter release in combination with “Mirror Lock-Up” mode to reduce camera shake, or if you have a more advanced camera that supports features such as Exposure Delay Mode and Electronic Front-Curtain Shutter, you can use those features to reduce, or potentially even eliminate camera shake. Lastly, don’t forget to turn off Image Stabilization / Vibration Reduction when your lens is mounted on a tripod.
The biggest challenge, however, was not when I was taking pictures of the half-lit or quarter-lit moon – it was when I was photographing a total eclipse, when the moon was in Earth’s umbral shadow. Depending on how bright the moon appears during this phase, you will have to adjust your exposure accordingly. Keeping my aperture between f/5.6 and f/8.0 and shutter speeds above 1/2 second, I had to increase my camera ISO to 1600 and sometimes even 3200, which added plenty of grain to my images, but at least the images were not blurry.
If you have a high resolution camera, you might need to use even longer shutter speeds to avoid blurring the moon. Ideally, get a proper motorized tracker such as the Sky Watcher, so that you can use longer exposures and lower ISOs without blurring the moon.
5) Focus Accuracy and Sharpness
No matter what lens you are using, getting a very accurate focus on the moon is extremely important. I know that some of you might suggest to shoot at infinity, but since many lenses now allow focusing “beyond infinity”, getting a true infinity focus is not that easy – a slight inaccuracy in focus will make the moon appear blurry. While using your center focus point to acquire focus might work fine when the moon is lit by the sun, your autofocus will most likely cease to function or might be grossly inaccurate when the moon is very dark. If you have a camera that has a LiveView mode, then certainly use it to get a much more accurate focus. I had some challenges with AF when using LiveView on my camera though – LiveView was severely overexposing the moon, which made it impossible to autofocus, even though I was shooting in Manual Mode. The workaround was to press the “OK” button on the Nikon DSLR (which switches LiveView to true manual mode), then rotate the back dial to increase my shutter speed. This way, I was able to properly expose the moon and AF worked great after that.
Instead of dealing with refocusing every time you take a picture, I highly recommend to switch off autofocus once you get an accurate focus on the moon (preferably before the lunar eclipse). Take a picture and use the LCD screen of the camera to see how sharp the moon is. Zoom in all the way and make sure that the moon appears sharp. If it is not, go back to LiveView mode and retry. If you cannot manage to get your camera to autofocus in LiveView mode, try manually focusing with your hand while zoomed in all the way in LiveView. If you get a good focus before the Moon goes into the Earth’s shadow, you won’t have to touch your focus until the end of the eclipse.
One more thing I would like to point out, is if you are using a lens with a teleconverter, or if you are using a consumer zoom lens, the optics are probably not very sharp when shooting at large apertures. Stopping down the lens aperture to f/8-f/11 should give you the sharpest results. Don’t use apertures smaller than f/11 (such as f/16 or f/22) – diffraction will kick in and make the moon appear even softer.
6) Moon Movement Speed
So far I mentioned several times how fast the moon moves when using long lenses. Take a look at this video and see for yourself where the moon starts in the frame, and then ends up at the end of the 2 minute video. If you are impatient, simply look at the beginning of the video, then the end and compare the location of the moon in the frame:
Now just think how many times I had to move my camera to photograph a 4 hour long eclipse!
Unless you are shooting at short focal lengths with a foreground object or some sort of a scene, don’t worry about composition – place the moon anywhere in your frame. The location does not matter, since you can easily crop the moon out in post-processing, as long as the moon is exposed properly. I often tried re-centering the moon in my frame, but as you saw from the above video, it was rather difficult to recompose every time. At the end, I ended up starting with the moon on my top left corner frame and let it move towards the right bottom corner. When it approached the bottom, I would move it back to the top left again.
If you want to have stars with the moon in the final picture, the best way is to shoot starts separately at several seconds, then combine both images together. If you want to have a composite image like the vertical one I posted in this article, then your best bet is to photograph a night scene separately with a wide-angle lens, then use Photoshop to copy-paste the moon into the image.
The post-processing method I use for the moon is described in detail in my “how to photograph the moon” article. For the total lunar eclipse, the bigger problem is going to be dealing with the noise due to high ISO levels. If noise is an issue, see my “noise reduction tutorial” that I posted a while ago – there are plenty of tips in that article on how to clean up noise in Photoshop and Lightroom.
As for doing composite images (combining the various phases of the moon with other images), the process is not that difficult. Here is how I recommend doing it:
- Pick a couple of photos with a dark sky, obviously shot at night.
- Open your moon photos and using the “Magic Wand” tool, select just the moon by itself. Play with the “Tolerance” level and make sure that you are grabbing the whole moon, not just parts of it.
- Copy the moon by pressing CTRL+C / Command+C
- Paste it into a corresponding image with a dark sky.
- If the moon you copied has some black edges to it and your sky is not totally black, then try this trick: select the moon once again with the Magic Wand, then right click the moon, choose “Select Inverse”, then right click again, choose “Feather” and give it 2-3 pixels. Next, click on the “Add a Mask” button on the layers palette. Once this is done, click on the Mask itself in the layers window, then click “Apply Mask”. Repeat this process several times, if necessary, to make the edges of the moon smooth.
- Experiment with copy-pasting several phases of the moon and see how you like the final image.
- Don’t forget about sharpening the moon. Do it before selecting the moon with the Magic Wand, otherwise the sharpening tool will also sharpen the edges of the moon.
Photographing a total lunar eclipse was a great experience for me. I highly recommend getting out and trying it next summer!