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Hi Trent & Julie,
if you are thinking of trying out some basic film astrophotography firstly you need the right sort of camera. A fully manual (no batteries required) camera, which tend to be the older models from the 60's and early 70's, that have a "B" and or a "T" setting enable you to do long exposures. If the camera has a B setting then you will need a cable release to hold the shutter open.
If the camera has a T setting then a cable release is not required (see the picture of the top of my old Nikon F, made in 1967, which has both settings on the exposure dial). Because the mirror flip in a single lense reflex (SLR) camera is quite aggressive and creates a large vibration at the start and end of an exposure, it is best to cover the front of the lense with a dark card prior to the start and finish of an exposure. With the T setting you just push the firing button to start, and turn the exposure dial to another point such as 1000th of a second to finish the shot.
Some of the later automatic cameras do have a manual override when it comes to doing time exposures so that the batteries aren't worn out at all.
A simple test of the film and camera is to do a few trailed shots on a tripod. I've attached an example here taken with a 50mm lens at f/2 (the lense wide open to get the most light) and let go for one minute showing the Pointers, Crux and Eta Carinae using FSX 400. To cut the star trails down you could shorten the exposure to say 45 seconds. Nearer to the equator you have to make it no more than 25 seconds to keep the stars close to round. Always record what you are doing so that you can learn from each session. Camera details, lense, f/ stop, exposure , subject, location, sky conditions etc. Give it a go sometime. You will be surprised at what you get
Bassnut,
I hadn't gone into it to that extent so I find that very interesting indeed! After 35 + years of doing this I find I still use the old (with the emphasis on old!) eyeometer. If it looks good then I am happy. If it looks coarse then I try to figure a way to overcome that. Even the grainiest of films can come up with a good result as long as the film is really saturated, i.e. exposed properly. No good doing short exposures with coarse grained films, unless you like that sort of effect.
Cheers
Coops
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