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A stationary camera can be used to photograph manmade satellites and rockets, comets, meteors, eclipses, star trails and more.
unmanned satellites...
At any given moment there are satellites galore passing overhead. Though they are quite easy to recognize, casual observers of the night sky may fail to distinguish them from high-flying commercial airliners. Airplanes are equipped with lights visible to ground observers; satellites merely reflect sunlight. Thus, they appear as a single, quietly-moving pinpoint of white light. Satellites do not blink or (ordinarily) pulse. Their paths through the sky are often somewhat arched. Moving in and out of the Earth's shadow, they may appear and disappear unexpectedly. No manmade satellites reveal their presence more spectacularly than the Iridium mobil civil communications satellites first launched in May of 1997. As of June 1999, 88 Iridium satellites had been launched. The operational system consists of 66 satellites in low, 420-mile orbits. There are 11 satellites in each of six orbital planes. Original plans called for 77 satellites in 7 orbits, thus the name Iridium, an element designated by atomic number 77. Iridium satellites look like three-bladed ceiling fans pointed at all times toward the Earth. Their door-sized antennae "blades" are fixed at 40 degree angles from the axis of the satellite body which measures some 13 feet in length. When the angle with the sun is just right, the antennae reflect sunlight as a brief "flare" which is bright enough for naked eye observations—sometimes even in daylight. Photographing Iridium satellites is quite easy. The challenge is knowing where to aim the camera and when to release the shutter. The link that follows is excellent satellite site. It provides extremely reliable predictions for when and where Iridium and other satellites will appear. Predictions typically pinpoint satellites in degrees of elevation (the height or altitude which they will appear above the horizon) and azimuth (generally, degrees from due north measured clockwise along the horizon).
A point straight overhead, the zenith, is considered to be 90 degrees above the horizon. If a satellite prediction indicates 45 degree elevation and 135 degrees azimuth, look for it half way between the horizon and straight overhead while facing to the southeast. Any common compass will indicate degrees azimuth. Estimating altitude is a little trickier. For a crude measurement, a fist held at arm's length is approximately 10 degrees. A sky map which indicates altitude is helpful. A 50mm lens provides a fair margin of error when it comes to anticipating a flare's whereabouts. A wider lens is even more forgiving, the trade off being that the flare will appear smaller on the film. Using a cable release, and with the camera mounted on a tripod and aimed towards the anticipated flare, attempt to capture the entire event on film; that means opening the shutter just before the flare erupts and closing it only after it fades. Doing otherwise will result in bluntly cutting off the flare's leading or trailing edge. As an aesthetic consideration and to give a sense of scale and location, it is good to shoot from a spot where it is possible to get a treeline, rooftop or other recognizable feature on the horizon into the frame.
To precisely anticipate the satellite's flare, it is important to have a clock which is accurately set (see the Universal Time link below). With the lens set at a half f-stop above maximum aperture (between f2.8 and f4 with a f2.8 lens), open the camera shutter about 30 to 45 seconds before the predicted burst. The flare takes several seconds to reach maximum brightness; it then simply fades away. At that point, close the shutter. The entire exposure will have taken about a minute or so, less if you chose to "cut it close" under brighter skies or with a "faster" (that is, smaller number) f-stop setting. For the record, I've had nearly identical results using 400 or 800 ISO film.
Photo of Iridium satellite 24 (above, top) was taken at 9:28 p.m. April 25, 1999, with a 135mm lens set at f2.8-4. It appears to wobble. An interesting composition resulted when Iridium satellite 55 (above, bottom) appeared by chance to slip between Altair and the fainter Tarazed in the constellation Aquila. Photographed in 8 p.m. twilight with a 50mm lens set at f4-56. An exposure of about 40 seconds on Fuji 400 ISO film. Estimated magnitude of -7.
My technique for photographing other satellites is similar although there are some additional considerations. For one, the magnitude (apparent brightness) of typical satellites is much dimmer than that of Iridium flares. Thus, it is more important to shoot beneath a darker sky to maximize the satellite's visibility. Longer exposures, though, come at the risk of "fogging the film," thus over exposing the sky—possibly obscuring the satellite—or creating objectionable, elongated "trailing" of adjacent stars. The SL-16 rocket shown below was exposed about 30 seconds under a rural sky at f2.8-4 using 800 ISO film. The negative was very thin but printable. An f2-2.8 setting may have been a better bet.
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