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Introduction to Meteor Photography
By Pierre Martin
 Basic meteor photography is a simple activity, requiring a rather
inexpensive setup. Meteor photographers love the Perseids, Leonids and
Geminids as they produce plenty of bright meteors and fireballs. It is by no
means easy. Meteors are too fast and they usually last less than a second,
which is too brief to try and "point and shoot".
A better method is to set a fully manual 35mm SLR camera (loaded with fast
film) on a solid tripod, aim it at the sky, use a time exposure of several
minutes and hope that a bright meteor will cross into the field of view of
your camera. Here is a list of what you need with tips to get you started on
meteor photography:
Camera Body
Use a fully manual 35mm SLR camera that does NOT rely on battery power to
keep the shutter open. Battery powered cameras will drain quickly as you
keep the shutter open for long periods of time. Choose a mechanical shutter
camera. A good inexpensive and reliable camera body is the Pentax K1000. It
is a bullet proof body. I had this camera drop on a hard surface and it
never failed despite that. Several great deals on other camera bodies can be
found in used camera stores.
Lens
The best lens for meteor photos are either 35mm f/2 or a 50mm f/1.4. The "f"
value refers to the lens opening or aperture. To record a fast streaking
meteor, you must open the lens as wide as possible. In other words look for
the smallest "f" number possible. Smaller number means larger lens opening.
A f/1.4 lens will show fainter meteors than what a f/2 lens is capable of.
The 35mm lens gives you a wider field of view, and gives you a greater sky
coverage to increase your chances of catching a meteor. The downside is that
most 35mm lens are of f/2.8, which will not record fainter meteors. On the
other hand, a 50mm lens gives you less sky coverage, but they generally have
more aperture (some as large as f/1.4 or f/1.2). I personally prefer to use
a 50mm lens, as the meteors appear as longer streaks. Most 50mm lens will
make meteors as faint as magnitude +1 or +2 (about as bright as an average
bright star) show up on the photo.
Guided or unguided
The more easy way is to simply set your camera on a solid tripod, and let it
expose the sky unguided. If you don't have a tripod, just prop the camera on
something solid, and have it point to the sky. Since the earth rotates, an
unguided exposure will show the stars as trails instead of dots. Star trails
will be all generally the same length. If you point your camera on Polaris,
you will get a series of concentric star trails, producing circles around
the north celestial pole. Polaris will be the star with almost no motion. If
you get lucky, a meteor will show up as a trail of different length and
brightness cutting across the star trails. Some people like stars to look
like stars, so they track their cameras to follow the motion of the sky.
There are different ways to track a camera, such as piggyback on a telescope
equipped with a motor drive, or a simple barndoor system.
Films
Because a meteor spends only a tiny fraction of a second on the emulsion of
the film, you will need high speed film to record it. Use fast films with
ISO speed of between 400 to 1600. In recent years, there has been a big
improvement with new better, faster and finer films. The faster films will
record more faint meteors but will also record sky glow and light pollution
much faster, which is not good. Colour film and slides are fine and will
give pleasant results. They are also widely available. On the other hand,
Black and White films are better for scientific study. When you get the
films processed, it is recommended that you ask to get the films uncut. The
developer may not know where the photo begins because of the dark sky, and
end up cutting all your frames right in half. It is also a good habit to
flood the very first exposure on your film with a bright light. Also, let
the processor know what type of photos they are dealing with. Most are not
used to seeing stuff like that. In my experience, I found that the quality
from the photos I get back can range anywhere from very poor to excellent.
Choose a reputable photo lab.
When's the best time?
Target your meteor photography attempts on nights when a meteor shower is
predicted to happen. This will increase your chances of "catching" one on
film. Favourite showers are the August Perseids, November's Leonids or
December's Geminids. Please refer to the list of showers for 1999 on the
links within our Meteor Section page. Also, more meteors will usually happen
after midnight and be at their highest levels the last hour before dawn.
Where to aim the camera?
Meteors can appear anywhere in the sky, so there is no best area to aim.
Meteors close to the radiant are short, and many dislike this effect.
Meteors very far from the radiant begin to spread thin and are more unlikely
to show up. Many astrophotographers feel that they increase their chance by
pointing the camera about 30 degrees away from the radiant and a little more
than half way up (between the horizon and the highest point in the sky).
Also take into account light pollution. Do not point your camera in the
direction of a city glow. This will probably wash out the sky on your photo.
Try to aim for the darker areas. It is also neat to frame a known
constellation such as Ursa Major or Orion. If meteors fail to show up, at
least you can get some nice constellations shots.
How long the exposure?
This depends on the darkness of your sky. From suburban locations, you might
want to expose for 3 to 5 minutes. A whole film's worth on a good night of
Perseids or Geminids might only show you a couple of photographed meteors.
You definitely increase your chances of getting more meteors by having
longer exposures. For best results, get as dark a sky as possible far away
from city lights of any kind. In dark skies, you could expose for over 20 to
30 minutes. When you see a bright meteor go across your field of view, stop
the exposure right away to avoid sky glow from ruining your meteor. Forget
about the fainter meteors going in the camera field. Most of them will be
too dim to show up at all on the photo.
Extra Gear
Here is a list of extras to make your photo sessions more enjoyable or
successful:
Cable release to go with camera body, so you can lock the shutter open and
walk away from the camera during its exposure. Hairdryer to keep dew away
from lens and keep yourself warm too. Also, consider chemical hand warmers
(available in most camping stores) as a good alternative to keep dew away.
Just stick them on the side of the lens. Pen and paper or recorder to keep
notes of your exposures and when you might have a possible meteor in the
camera field. Take notes of the date, beginning and end times for each
exposure, type of film used, type of lens used, sky conditions, locations,
etc...
Submit your photos
It is also possible to record meteors photographically for the purpose of
scientific study with minimum equipment required. Photography is a very
valuable method that may help to determine precise locations of shower
radiants, velocities with the use of shutter blades, etc... The
International Meteor Organization collects photographic data from amateur
astronomers from around the world. For more information on how to get
started on a photographic program, please visit the International Meteor
Organization (IMO) site. They have detailed information available on the
topic of serious meteor photography. |