Taking a photo of an eclipse is really more like looking through a telescope and recording what is coming down through the lens.
In fact a telephoto lens is nothing more than a telescope, albeit one that can be attached to a camera body.
When you look through a telescope at the heavens, you're going to get a much steadier view if it is mounted on a stand.
The same is true of a camera, which can be mounted on a tripod. It's also possible to use some other means to secure the camera, perhaps some heavy sandbags placed in such a way that the camera can be propped up against them.
The only problem here is that due to the inconvenient design of most cameras, it may be difficult to look through the lens and frame the shot.
If it's difficult to see through the viewfinder, it may be possible to hook the camera up to a laptop computer and see what the camera is seeing on screen.
At first I tried securing the camera by holding it against the wall of the house, but there was still a tiny amount of camera shake, magnified by the zoom lens, so I used a tripod.
The more powerful the lens, the better the view is likely to be. I used a 300mm zoom lens attached to my Nikon D100, equivalent to 450mm on a film camera. Even at this powerful focal length, the moon was only a small disc in the centre of the frame.
Once you've found the moon in the sky, you need to get the focus right. Your camera may be achieve this using autofocus, or alternatively, it may be necessary to adjust the focus manually. As a precaution, if it's possible to view the photos at large size on the laptop to check the focus is correct, it's worth doing.
First test shot, fuzzy, too dark, out of focus.
But we are not far off the right exposure. This is f5.6 and 3 seconds
Once the camera is secured in place, and the focus is set, you are ready to start taking photos.
You will need to take photos at a range of different exposures in order to find the optimum exposure. It is highly unlikely the camera's metering system will be able to find the right exposure. First set the exposure to manual, taking note of the aperture and shutter speed settings, and then do a series of bracketed exposures.
The shutter should be set to 'timer' so that you can press the button and wait a few seconds for the camera to take the photo. This ensures there is no camera shake. You could also use a cable release, but the moon isn't likely to make any sudden movements, so I'm happy to use the timer.
F5.6 and 3 seconds seems about the optimum exposure. Getting the image sharp can be difficult.
A little sharpening in Photoshop can improve things. Here, sharpening has been applied to the left half of the moon.
Start shooting and take a look at what comes out. Too bright, stop down the lens to a smaller aperture (lens opening) and/or adjust the shutter speed to a faster time to allow less light to enter.
Too dark, do the opposite. Capture a range of exposures, check on the laptop or continue.
By the way, if you don't have a laptop, then in my opinion you should get one, and preferably an Apple Macintosh iBook or best of all, the MacBook Pro. I consider a laptop to be absolutely essential when using a digital camera, as you need to download and check photos as you go along.
Lunar Eclipse Test Shot: At F32 and 2 seconds, the image is too bright, details are 'burnt out' to white.
By carefully adjusting the exposure you will find the optimum exposure. Ideally no part of the moon should 'burn out' or turn white. The brightness range from the brightest tone on the moon's surface should be within the exposure range the camera is currently set to. It's better to be a bit underexposed than a bit overexposed. You can lighten areas that are a bit too dark, but you can't darken areas where detail has been lost due to over-exposure.
There is an important difference in light intensity between the full eclipse phase and the phase where the moon is emerging from the earth's shadow. In the full eclipse phase it is quite dark. I calculate that the fully lit moon is around 8 times brighter than during the eclipse. When fully illuminated by the sun, the moon is as bright as daylight and requires a shutter speed and aperture comparable to what you'd use during the day in bright sunshine.
At a lower exposure level, the image is within the acceptable exposure range.
This is f32 and 1/2 second.
And that's all there is to it. Not difficult at all. Once you've downloaded the photos and selected the best ones you can mount them in a composite image as I've done.
There are few photographic subjects more majestic and captivating than the moon, especially during an eclipse. My composite photo brings back memories of seeing the first Moon landings in the late 60s, when NASA released many stunning images of the moon and earth.
It's very satisfying to be able to get a photo that looks every bit as impressive as those NASA photos using just a regular digital SLR and a zoom lens in my back garden in Manchester.