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Here are some pointers to help you capture great close-up photos of Sunday’s big show.
SkyNews editor Gary Seronik recorded this view of the April, 2015, total lunar eclipse with an 8-inch reflector telescope and Nikon D5100 DSLR camera. The 2-second exposure was shot at ISO400.
A total lunar eclipse is a wonderful sight to behold—and if you have clear skies on Sunday night, you’ll be able to take in the event with your eyes alone or with binoculars. (Eclipse details can be found in the January/February issue of SkyNews and here.) But some will want to capture a photographic souvenir.
There are many ways to record the eclipse, but if you want to get a close-up shot, the best approach is to attach your camera to a telescope. If you have a digital SLR (DSLR) or “mirrorless” camera and a scope with a motorized tracking mount, you can employ prime-focus photography to get a lunar-eclipse image like the one shown above. Here’s how to do it.
The ideal telescope is one with a focal length that allows the Moon’s disc to very nearly fill the short axis of the image sensor. For a “full frame” DSLR camera, something around 2,200 millimetres is nearly perfect. That means an 8-inch scope working at f/11, or a 10-inch f/9. If your DSLR has a “cropped” or “APS-C sized” sensor (as most do), then a telescope with a 1,500 mm focal length fits the bill. An 8-inch f/7 or 10-inch f/6 is a good choice.
For the photographs shown here, I used a home-built 8-inch f/4.5 Newtonian with a focal length of around 820 mm. The image scale was a bit small, so I attached a 1.5× teleconverter to my camera, which boosted the effective focal length up to 1,370 mm.
If your telescope’s focal length is less than ideal you can still get pleasing results, though you may have to crop your photos a bit to compensate for the smaller image scale.
To attach a DSLR camera at the prime-focus of a telescope, you need a T-ring (left) and a prime-focus adapter tube.
For photography with your telescope, you need two extra pieces. First, a T-ring-adapter for your specific make of camera. This is a simple fitting with female T-threads in front and a bayonet flange on the rear to match your camera’s lens mount. T-rings are available for most popular camera brands and models. You’ll also need a prime-focus adapter tube. This piece screws into the T-ring and allows you to attach your camera to your telescope’s focuser.
Depending on the specifics of your camera and telescope combination, and the brightness of the eclipsed Moon, the optimum exposure time will vary considerably. Expect your exposure to be several seconds long, depending on the ISO setting you’ve chosen. That’s why you will most likely need a motorized mount capable of tracking the Moon to prevent the image from blurring during the exposure.
As this pair of images demonstrate, the brightness and colour of the eclipsed Moon can vary considerably. You will have to compensate by using different exposure times. Courtesy Gary Seronik
DSLRs have improved greatly in the past few years, so if your camera is of recent vintage, you can probably use ISO 1600 or greater without fear of introducing a lot of image noise. Older cameras will likely need to stay at ISO 800 or lower. As you increase the ISO, you can reduce the exposure time, and vice versa.
Set your camera for daylight white balance (usually a Sun symbol on your camera’s menu display). “Auto,” or any other setting, will give your images an unnatural colour cast.
Firing your camera’s shutter is likely to introduce image-blurring vibration. If your camera is equipped with a mirror lock-up feature or exposure delay mode, here’s where it comes in handy. In any case, you want to be sure to use a remote shutter release if you have one.
If your camera lacks these features, here’s a handy trick. Get a piece of black cardboard bigger than the front opening on your telescope. Set your camera’s shutter speed for one or two seconds longer than required for the correct exposure. Hold the card in front of the scope so that no light makes its way down the tube. Now, fire the shutter and wait a second or two for vibrations to die out, then move the card out of the way to begin your exposure.
Experimentation is Key
This trio of images from the February 20, 2008, eclipse shows the Moon’s passage through the umbra, the darkest part of the Earth’s shadow. Courtesy Gary Seronik
Fortunately, a lunar eclipse lasts for a long time—photographing one is nowhere near as frantic as with a solar eclipse. That means you have time to try different exposure and ISO combinations until you find the one that works best for your set up. How will you know if your exposure is correct? The most reliable way is to check your camera’s histogram display—especially the graph that corresponds to the camera sensor’s red channel. Watch for “clipping” — the histogram data crowding up against the right side of the graph.
Finally, to maximize your chances for success, it’s a good idea to setup your gear a night or two before the eclipse and perform a dry run session photographing the Moon. There’s nothing like actually going through the entire process to ensure that your gear is working properly and that you know how to use it.
For many Canadians, the season’s typically inclement weather makes seeing the Sun on the date of the winter solstice something of a rare treat. Getting to see its complete arc across the sky—from sunrise to sunset—is rarer still. Indeed, Edmonton, Alberta, photographer Luca Vanzella had to combine images captured over two consecutive days to create the image presented above. However, as Luca notes, “There is a window of about nine days centred on the winter solstice, when the Sun rises and sets within a tenth of a degree of its most southerly positions.” And though he didn’t get his much hoped for clear day, Luca was able to record the afternoon half the solar path on December 18, and the morning portion on the 19th, for a seamless composite.
Luca used a Canon EOS Rebel 3Ti DSLR camera and a Canon EF 8-15mm f/4L Fisheye USM lens (at 12mm) to obtain a combination of Sun images shot through a solar filter (spaced roughly 15 minutes apart) and unfiltered foreground shots.
The famed Orion Nebula, M42 (and its companion M43), has been imaged countless times. M42 is one of the most popular deep-sky targets for obvious reasons: it’s big, it’s bright and it’s beautiful. Each winter we receive a new crop of impressive photos, but in spite of that, no two are exactly alike. Different equipment yields different results, but much of a shot’s final appearance is determined in the processing stage. What happens there reflects the tastes and intentions of the imager. Some try to show every last wispy detail in the nebula, while others aim for something more closely resembling the telescopic view. Either approach can yield breathtaking results.
Yanick Bouchard recorded this portrait of M42 from the light-polluted environs of Mirabel, Quebec. He used a Celestron EdgeHD 925, 9¼-inch telescope with HyperStar (for a focal ratio of f/2.3) to capture a total of 198 minutes exposure with a ZWO ASI1600MC cooled colour CMOS camera.
Lac du Caméléon Storm Cloud by Jean François Fortin
Last August, Quebec photographer Jean François Fortin set out to capture the Milky Way from Lac du Caméléon. His plans were temporarily thwarted by a lightning storm that illuminated the sky every five to ten seconds. The storm eventually quieted down and he was able to get his Milky Way shot, but arguably the photo presented here is the catch of the night. “I took many pictures of the storm, but this one is the best. I particularly like the blue halo on the top of the storm, and the tiny lightning bolt on the top left side,” he says.
Jean-François used a tripod-mounted Sony Alpha a6000 digital camera at ISO 3200 for this single, 15-second exposure made with a 24mm f/1.4 lens. To see more of his photography, turn to page 46 of the January/February 2019 issue of SkyNews.
The night sky is full of wonderful, mysterious and beautiful sights. And as familiar as many deep-sky denizens are, there are plenty more to discover. Take NGC7129 in Cepheus. It’s rarely photographed despite being a fantastically interesting object. The nebula’s blue-tinted dust haze is illuminated by a clutch of newborn stars (perhaps only a few million years old) while the tiny, crescent-shaped red strands are Herbig-Haro objects energized to luminescence by ultraviolet light.
Roger Ménard photographed NGC7129 from his backyard observatory in Sainte-Sophie, Quebec. For the final image he combined a total of six hours exposure data (shot through red, green and blue filters) captured with a ZWO ASI 1600MM cooled CMOS camera and a Celestron Edge HD 14 telescope working at f/7.7 (with focal reducer).