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THE BASICS OF ASTROPHOTOGRAPHY

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ASTROPHOTOGRPAHY FOR THE BEGINNER

Getting Started: The Equipment

The Camera: To do astrophotography, it is obvious that you will need a camera. What is not so obvious is the type of camera that is best suited to astrophotography. Point and Shoot automatic
do everything cameras are not suitable for this purpose. The best camera to use is a manual 35mm everything cameras are not suitable for this purpose. The best camera to use is a manual 35mm SLR (single lens reflex) camera. The following features are a must for any camera which is to be used for Sky shots.

1. The camera must have the ability to do long time exposures (the "B" setting)
2. The camera should have removeable/interchangebale lenses
3. The camera should not require the battery for operation
4. The camera should have the ability to accept a remote shutter release cable
5. The camera must have a tripod mount threaded hole on the bottom

If you have a camera where the light meter no longer works, no problem (you won't need it for night sky)

There are many cameras available with meet this criteria. One good camera for astrophotography is the Pentax K1000. It's very basic but a quality camera that fits the bill. Other cameras that are good for astrophotography are the Pentax ME super, Canon FT and Nikon FM and the Olympus OM 1. The best cameras for astrophotography are often the low end models.

The Lens: The standard 50mm lens is a good one to start with basic astrophotography. Most 35mm cameras come with this lens. The quality of lenses can and does vary. Astrophotography is one of the most demanding tests anyone can give a lens. Most lenses are of decent quality. . Higher quality lenses will have a faster "F" ratio (F1.4 or F2), they will have premium optical glass and special coatings. All this is fine if you are willing to spend the money, but most of the standard 50mm lenses that are supplied with the basic SLR Kit will take decent astrophotographs.
Another lens that is good for the beginner is a 28mm wide angle lens. This lens will permit you to photograph a larger area of the sky.

The Tripod: Even the most basic astrophotographs require a sturdy tripod. It does not have to an expensive one, it just has to hold the camera steady. Many Astrophotos require exposures of 30 seconds to hours. The tripod should have enough motion to allow you to point the camera to any position in the sky.

The Shutter Release Cable: Very Important! In order to take photos without moving the camera, a locking cable release is a must. Prices range from $10-40. Remember, you only get what you pay for.

The Film: Choosing the proper film is the most important aspect for the Beginner. Best Films to use are: Fuji colour 400, Fuji Super G800 , Fuji colour 1600 and Konica 3200.
Remember: The higher the number - the more sensitive the film is to light
requiring a short exposure

Your First Astrophotograph
Your first picture should be an easy target such as a constellation. A good starting point would be the Little Dipper with the North Star. This type of astrophotography is call "Wide Field ". With these types of shots you do not need a telescope, just the items listed. Load the film into your camera and advance it to the first shot. Mount your camera on a tripod and attach the cable release. Set the F stop on your lens to its largest opening usually F/2 and be sure to set the focus to infinity! Aim your camera at the desired region. Be careful not to aim the camera in a direction where there is a lot of sky glow or street lights as this will fog the film.
Now open the camera's shutter and begin to time your exposure. Try one for 15 seconds, 30 seconds and 1 minute. Then try 1/2 hour and a 1 hour exposure of the North Star. When the film is developed you will notice the the stars have trailed in circles around Polaris. This is due to the rotation of the Earth.

10 minute exposure Other objects of interest you may capture are man-made satellites, these appear as diagonal lines across the film and meteors that appear as a bright short streak.

Once you have finished your roll of film the best place to have it developed is a "One Hour Photo Finisher" The reason being that you can personally give instructions for processing to the person that does your film. Mention that many of the shots, if not all, will be dark compared to regular shots and to print them all regardless what the machine says. Tell them not to cut the film as the borders between frames of astrophotos are hard to detect. The prints you receive may not be perfect the first time around. Some will need darkening or lightening and others, colour correction. Save the best prints so you can have a reference to show the photo operator what the photos should look like in general.

To keep stars from trailing when using a fixed camera, be sure to keep your exposure times short. Because you have a limited exposure time with a fixed camera,
Use the fast ISO 800 to 3200 film to capture as many stars as possible during that exposure.

Lens Focal   Celestial   Approx. 45°      Celestial
Length      Equator     Declination        Poles
   28mm       25 sec        40 sec           90 sec
   50mm       12 sec        20 sec           45 sec
135mm        5 sec         7 sec           16 sec

Using this method, you'll be able to pick up stars fainter than you can see with your unaided eye. To
record even fainter stars you require exposures of several minutes. To prevent the stars from trailing one inexpensive technique is to use a camera tracker.
You can buy them commercially but one design, the Barn Door tracker, is easy to build yourself.

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