There are already enough great reviews to help you decide whether or not the Nikon FM10 is the camera for you, so I won't write another one. This one is a bit esoteric--it only discusses the suitability of the FM10 for astrophotography, an admittedly small subset of the camera market. Instead of giving a general review of the camera, I'll try to cover the pros and cons relevant to astrophotography.
Commenter "uniq" reminded me that much of what I say also applies to nighttime photography--that is, photos taken at night without benefit of flash of subjects other than the stars and planets.
Pros
1. The camera is completely manual and doesn't require battery power to operate.
One of the fancy new auto-exposure / auto-focus cameras is exactly what you don't need for astrophotography. All-manual is the way to go for several reasons:
First, auto-focus often doesn't work well in the dark or in low contrast situations, and you're more or less always focused at infinity anyway. Furthermore, there are techniques that involve manually changing focus for effect or to make the color of a star more obvious.
Second, exposure times tend to be very long, with many minutes to hours fairly common. Many--if not most--newer cameras use battery power to hold the shutter open, so battery life would be a serious problem. The FM10 works perfectly well for astrophotography even without a battery (which is used only to power the light meter).
Third, the FM10 accepts the inexpensive screw-in type of mechanical shutter release cable rather than an electrical shutter release, which again, would require battery power.
2. Nikon lenses.
Aside from their excellent quality, Nikon lenses offer compatibility across almost its entire product line: a 20-year-old Nikon lens will probably work on your new FM10. Furthermore, there is a huge supply of secondhand Nikon and Nikon-compatible lenses. A 50mm f/1.8 is a good starter lens for astrophotography. Faster is even better, but tends to get expensive. Furthermore, Nikon continues to develop new lenses that are compatible with its older cameras, unlike some other companies. [For technicalities about the Nikon AI mount, just search the web.]
3. Light weight.
The FM10 is relatively light compared to some (especially older) 35mm cameras. This is an advantage when you piggyback your camera on a telescope or mount it at the prime focus. It's also helpful if you are using a do-it-yourself barndoor drive mounted on a tripod.
4. Mirror prefire.
One source of camera vibration is the movement of the mirror to its retracted position just before the shutter is opened. The FM10 uses the prefire technique to move the mirror up enough in advance of the exposure so the vibration is pretty much gone by the time the shutter opens.
5. Allows double exposure.
The FM10 has a tiny lever that you can hold to prevent the film advancing when you operate the film advance lever. This is probably more useful for "art shots" than serious astrophotography. Unfortunately, the lever is very small and a bit awkward to operate, but at least it's available.
6. Availability of accessories.
For your astrophotography adventures, you'll eventually want to take pictures through a telescope. For this, you'll need a Nikon-compatible T-adapter and one or more screw-in T-mounts for different sized eyepiece holders. These accessories and many others are very readily available new from Nikon and other suppliers or at much lower cost (and completely acceptable quality) in the second hand market, most readily on eBay.
Cons
1. Lack of interchangeable focusing screens.
The objects you photograph in astrophotography tend to be small, and stars are dim, so you need all the focusing help you can get. For deep sky work you usually want a fine matte screen, and for lunar or planetary work, a clear central spot with crosshairs. Unfortunately, the FM10 does not allow replacement of its medium matte screen. Still, I've found focusing of bright objects like the moon is pretty easy, and focusing for stars is easy enough if you just find a bright one.
2. Some autofocus lenses are not fully functional.
You may be able to mount all Nikon lenses on the FM10, but that doesn't mean all the lens features are available. Some lenses lack an aperture ring, and so depend on the camera body to control aperture. In the absence of control input from the camera body, they just sit there at their smallest aperture. This is a serious limitation for astrophotography, where you want all the light gathering power you can get. Just keep this in mind when selecting lenses or considering compatibility with lenses you already own.
3. Starter package isn't exactly right.
The FM10 is most often sold in a starter package with a 35-70mm zoom f/3.5-4.8 lens. While this offers some flexibility in composing images, you'd be much better off in terms of light-gathering power with a 50mm f/1.8 or faster lens. If you can find the camera body and appropriate lens separately, you'll be better off. There seems to be no end to the supply of such used equipment on eBay.
Reader "uniq" points out in a comment that the 35-70mm zoom isn't even a great lens for this camera's intended market, beginning photography "students." Even they would probably be better off with a fast 50mm lens.
Useful Links
Nikon also makes some great binoculars for amateur astronomers. Check out my review of
Nikon binocular.
For great deals on Nikon and a huge variety of other photo, video and electronic stuff, check out my review of
BH Photo-Video.
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To see an image of the Milky Way I recently took with an FM10, check out
http://home.netcom.com/~jsquare/Pages/Milky%20Way.html
Abe's Of Maine
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