Rare Moon event coming up
Since humanity started to walk the planet, we had a fascination with the moon and continued to do so until this very day. We worshipped it as a god, we associated it with romance and werewolves, and we even visited it once to demonstrate humanity's abilities. Why this love affair with our nearest celestial neighbour? I am not sure, but a love affair it is indeed.
Wednesday, 31 January 2018 will present an opportunity to observe a total lunar eclipse from where we live in Australia. The last event of this kind was in 1866 and can best be described as a Super Blue-Blood Moon. Of course, it is a regular eclipse like all other. The term "super," relates to when the full moon is closest to Earth in its annual orbit around our planet, which is commonly known as the Super Moon. It makes its appearance about 7% bigger than usual. It is also the second full moon during the same month, which is otherwise known as the "Blue Moon," hence the expression "Once in a blue moon." And then when the Moon moves into the umbral shadow of the earth during the eclipse it turns a deep orange to reddish colour deriving the term "Blood Moon." The atmosphere acts like a filtered lens. It bends red sunlight into our planet's shadow and scatters out blue light. It's the same reason why sunrises and sunsets appear reddish. This red coloured Moon is the most beautiful part of a lunar eclipse.
PREPARATION
To observe the eclipse is easy. All you need to know is when and where to look out for it. When you plan to photograph the event, things get slightly more complicated, and therefore careful planning and preparation are essential.
An eclipse of the moon is newsworthy and will be announced in the media in the days leading up to the event, although detail is not always comprehensive. I use the website https://www.timeanddate.com as it provides most of the information required for the preparation. The advantage of this site is that it allows for an eclipse calculator that will calculate the date/time for your specific location and provide you with useful illustrations of when and where to look for the eclipse.
So once you are on the timeanddate.com website, navigate to the tab "Sun&Moon" then onto sub-tab "Eclipses." A list of eclipses will appear with the January 31 lunar eclipse at the top of the page. Next type in your town/city name in the top right-hand corner and press the "Go" tab.
I plan to be in my home city of Mount Gambier (South Australia) for the eclipse. The below table from for Mount Gambier shows that the eclipse starts at 9.21pm as the Moon climbs through the Eastern horizon after dark. The maximum of the eclipse will be at 11.59pm, and by 2.38am it will be all over. For the first two hours the eclipse is quite uneventful, but around 11.21pm the Moon will start to turn red. The little earth map in the top right-hand corner shows that only specific regions in the world (dark blue) will observe the full eclipse. Africa and most of South America won't see the eclipse at all. People in Asia and Europe will see part of it. In the eastern parts of Australia, we are lucky to see the full eclipse, weather permits.
The next planning stage is to research the weather conditions at the time of the event. No matter how good the predictions are, the weather will be what it is at the time of the eclipse, and we cannot influence the outcome. Just accept it and if you're serious about it, travel to a different region with better weather prospects. I experienced this first hand during the lunar eclipse of 15 April 2015. I hired an expensive 600mm lens and set up camp on the Mornington Peninsula, just to be frustrated by low cloud, while my mates 70km north enjoyed and unobstructed eclipse. With the October 8, 2014, eclipse, Mount Gambier was about the only big city in the entire Australia with a clear sky. Luck plays a significant role, and you can only hope the weather will be kind to us on the night.
If you are not planning to photograph the event, the next session will be too technical and I reccomend you skip and enjoy your eclipse through visual observation.
If you plan to photograph the event, then your next planning step is to get your gear ready. I usually do this a day in advance. It is best to develop your own checklist to make sure you tick all the items required. You will be surprised at how many times photographers rock up at a photo shoot only to have <15% battery life left, or they forgot their tripod. I have the following essential items on my check list:
CAMERA
It is not possible to prescribe a specific camera type or brand for this kind of work. Today's cameras are all good, and most will do a reasonable job. Most DSLR's and high-end micro four third cameras and rangefinders are suitable. Unlike common belief, lunar work doesn't require a full frame camera with high pixel and high ISO ranges. When I first started photographing the Moon, I overexposed continuously, as it is the second brightest object in the sky besides the Sun. Make sure your camera is capable of the following: (Check out your camera's manual or ask someone knowledgeable to help you)
Able to switch to the manual ("M") mode
manually control shutter speed in the M mode,
manually set lens apertures in the M mode
change ISO settings
manual focus
white balance control
switch off anti-vibration control
timer shutter release or remote shutter release
LENSE CHOICE
As with cameras, you don't need fast expensive lenses with low apertures. The standard >4 f-stop lenses are excellent for the job. The choice of lens diameter is essential. In the composite photo below taken on 8 October 2014, I used both a wide angle and a telephoto lens to capture the different elements of the composite image. A composite is an image that consists of a combination of pictures or photos, put together with software like Photoshop. For example, the composite below is a combination of 16 individual photos taken on the same night. A wide-angle (14mm focal length) landscape for the canola field background and 15 individual moon images, shot with a telephoto lens. (200mm focal length)
For wide angle work, use a lens with a range between 12mm and 35mm (35mm equivalent)
For telescopic work use a lens with a range between 200mm and 600mm (35mm equivalent)
If you don't contemplate doing a composite for special effect, it is okay to use either a wide angle or a telephoto lens to shoot single images. Extreme wide angle and telescopic lenses are expensive to purchase. There are two solutions to overcome this. First, consider renting your gear. Camera retailers in the bigger cities and towns have renting departments, where you can rent equipment at a reasonable price. If your camera is limited, rent one and experiment with it until you find out what works best. If you don't have a telephoto lens, rent one. Handy to first rent, before you make a buying decision. In Mount Gambier, we don't have camera rentals, but in cities such as Melbourne and Sydney, they are commonplace.
The other solution is to use a teleconverter. A teleconverter is a low-cost option (looks like a narrow ring) designed to be fitted in front of a standard lens to increase its effective focal range. It, for instance, change a 200mm focal range into a 400mm field, using an x2 teleconverter. They are cheap and effective. You lose a bit of definition and clarity in the process, but it won't even be noticeable. Non-full frame cameras with smaller sensors also help with cropping and don't require expensive lens gear to obtain a reasonable close-up image.
TRIPOD
It is always good to invest in a good quality tripod. You don't need a $1,000 one, but $200 will buy you something that will last a lifetime if looked after properly. The modern day carbon fiber tripods are light in weight and are sturdy enough to keep your camera steady, ensuring a crisp and clear image. As the moon's traject can span across 180 degrees, its best to buy a ball head that will allow the camera to swivel through the entire span with ease. I don't own a ball head, and it becomes difficult to aim at the moon, the higher the moon moves above the horizon. With frustration I had to adjust the tripod leg heights to achieve the same outcome, resulting in a less stable configuration. Once again if you don't own a tripod, borrow or rent one.
SMALLER ITEMS
A small torch to navigate around in the dark. Cover the front lens with red cellophane, as your eyes are not sensitive to red light and you will not be blinded.
A Dry lens cloth - Throughout the evening condensate might start to build upon your lens surface and need to be wiped dry.
A Remote shutter release is useful to help reduce camera shake. It is a small receiver device that attaches to the camera's hot shoe (where the camera flush mounts onto) and receives signals from a small handheld remote control panel, to open or close the camera shutter. If you don't have one, you can also use the shutter release timer, to trigger the shutter. It is as effective, and I use it all the time. With a telephoto lens allow 6 -12 seconds on your timer to open the shutter.
THE SHOOT
It is custom for me to do a test shoot the night before the eclipse. I recommend it, in particular, if it's your first attempt. You obviously won't have the eclipse, but you will familiarise yourself with your surroundings and can do trial and error work with your exposure settings. It will increase your confidence levels and iron out out all the technical stuff. It also gives you the opportunity to research exciting background options in the landscape if you decided to do wide angle or composite images.
On the evening of the eclipse, make sure you arrive half an hour before the eclipse is due to begin and do your last minute preparation. Make sure you have a clear line of sight to the horizon and that trees or other objects don't block your view. Make sure you have a level area to park your tripod. Unlike with deep sky astrophotography, a complete dark site is not a requirement. You can shoot within the city boundaries without loss of image quality. Just make sure you don't have a direct light such as from a streetlight that can cause lens flare and shadow effects. Dark sites will result in better image quality, but it is not essential. When shooting wide angle, city lights naturally becomes more critical as they can flood out the moon's light, although many photographers prefer to have a city skyline as background.
Once again, no single camera type or brand is the same, and it is therefore impossible to provide you with specific camera settings. During your trial shoot, you can leave your camera to determine it's own settings and see what results you get. I prefer to switch the camera to its manual setting and find the result is usually much better. I apply the following camera settings:
Switch to the manual "M" mode, as this allows you to control the shutter speed and lens aperture
Switch ISO to a constant 200 setup, once again the moon is bright, and you don't require a high ISO setting
Switch your White Balance to daylight; this keep WB constant across a series of photos
Switch your camera or lens to the manual focus setting
If your lens has anti-vibration control, switch it OFF
Put your camera on a timer shutter release mode or connect a remote control shutter release to it.
Make sure your camera is mounted on a tripod
A lunar eclipse only happens when the moon is full and therefore very bright. As the moon enters the eclipse, the brightness starts to drop, and the moon changes colour at the same time going from white to red to almost dark. By the time the maximum of the eclipse is reached, the Moon is dark and emits very little light. As a telephoto lens (> 200mm) gathers much more light than a mid-range focal length, you will have to make dramatic setting changes to achieve a balanced exposure. I keep my camera ISO setting constant at 200 and my f-stop at 8 for the duration of the shoot, and therefore the only variable is the shutter speed to control the exposure.
Once again there is no magic formula or settings that I could prescribe. I found a useful guide developed by Fred Espenak at http://www.mreclipse.com/LEphoto/LEphoto.html can be of help. Let's use my settings as an example. I told you I use a constant ISO of 200 and f-stop 8. Go to the table and find ISO 200, 4th row from the top. Move your eye horizontal three columns where you will find f-stop 8. Drop down in that same column and read off the shutter speed setting. No eclipse = 1/1000sec; Partial eclipse = 1/500 to 1/15sec and total eclipse = 2sec to 8min.
With my camera on the above settings and mounted on its tripod, I open the "Live view" mode. I prefer to use the "live view" mode to the viewfinder. That way I can make sure the image of the moon is in the middle of the frame, but most importantly, I can apply manual focus to make sure the moon is in sharp focus. In "live view" you can magnify the moon up to 10x's, which helps to obtain crisp/sharp focus. As the moon is bright and big, you can also use autofocus to guide you, but I found that when the moon goes into the last phase of the eclipse, the autofocus mode fails most of the time and will frustrate you. A third important reason for using "live view" is that the camera's mirror is already in the up position and don't cause any vibration when the mirror flips up.
The secret of lunar eclipse photography is to use a quality telephoto lens, high f-stop to obtain a depth of field, to focus sharp, to avoid camera shake and not to over or under expose with the variable brightness during the eclipse. It takes time and practice to achieve a good outcome, but it is undoubtedly quite rewarding.
With my 200mm focal length, I will do an exposure every 10 minutes to get a good spread of images across the entire eclipse cycle. If a particular image is not in focus or something went wrong with the exposure, I can use the next image in the sequence. For most people, it is rewarding to capture the moon when it turns into that deep red colour when it moves into the earth shadow.
POST PROCESSING
These days a lot can be achieved through post-processing of images. If you so choose, you can use post-processing software to enhance your moon images further. If you are exposed correctly, there is usually very little you have to do in post-processing. In the sequence below you will note the moons to the right is more yellow in colour to the ones on the left. The eclipse began when the moon was just over the horizon, and the light had to travel through more significant layers of the atmosphere causing the yellow tint. You see this every time the full moon comes up, going from yellow to white as it climbs away from the horizon. If you want to make a composite image to illustrate the sequence of the eclipse, you will have to have a good knowledge of software like Photoshop. I don't have the skill an outsource it to a company in the Philippines.
Photographing a lunar eclipse require quite good knowledge of your equipment and high technical skills to achieve a good outcome. You can obtain reasonably good results with most hardware and cameras if you put a bit of effort into your preparation. Good luck with the upcoming event and I wish you a clear sky on the day. If it all sounds too technical to you, sit back and just enjoy the eclipse.
