This isn't going to be a scanner review, but I will say this: If you're in the market for a new scanner, do your homework. Whether you're a pro or an amateur, keep in mind that there's no one scanner that can do it all.
I like to scan my film using a pretty high-quality film scanner, like the Nikon LS-4000. This scanner offers up to 4000dpi, and results in a 45MB file when used at its maximum potential for a 35mm frame. It also has a feature that removes dust and scratches. However, there's a good deal of prep work to make sure each scan is done perfectly.
At lower settings, the time is reduced significantly. The trouble is, high-end film scanners like these can be pricey. The latest 35mm model from Nikon sells for about $2500.
This setup is great for scanning my best work. A 45MB scan from the LS-4000 printed on a decent ink jet printer can make an amazing enlargement—far better than I could ever make in the darkroom.
For speedy scanning of just about anything, I turn to flatbed scanners. Most flatbed scanners these days make a pretty decent scan from 35mm or medium-format slide or print film. Many will even allow you to mount up to 12 frames at a time, making batch scanning a breeze.
If you have boxes of old prints whose negatives have long been discarded, a good flatbed scanner is essential. If you really have to make a choice between buying a flatbed or a film scanner, I'd suggest starting out with a decent flatbed that scans film. You can always have your best images scanned professionally at a lab, which brings me to my next point.
You may want to have your film archive scanned by a professional. If you don't have the time or can't justify spending the money for a scanner, there are many labs out there on the Internet (and possibly right in your own home town), who will take your collection of film and, for a hefty fee, offer to make printable scans of whatever you want. The fee may be nearly the cost of a good scanner, but you won't have to invest any of your time doing the dirty work.
Another option you have for quickly digitizing a film and print archive is a duplicating setup. For slides, you can buy a pretty inexpensive gizmo that fits on the end of your digital SLR's lens. All you do is stick the slide in the other end and point it toward a nice, even light source. The digital camera records the image at a 1:1 ratio and you have your digital duplicate at your camera's resolution. The quality of this type of setup depends on a few factors though, so some tests may be in order. First, there's the quality of the lens. A good macro lens might be necessary to provide the flattest field of view (also good to have for copying flatwork). Your camera's ability to record a fairly linear tone curve will also come into play.
For digitizing prints, you can also try to set up a copy stand with your digital SLR and a macro lens. The trick to a good copy stand image is in making sure the flatwork is flat, and the lighting is perfectly even. The supplies are relatively cheap and if you're inventive, you can build a decent setup out of cheap high-wattage lamps, a few high-back chairs and a coffee table. Make sure to flatten your work with a piece of high-quality picture framing glass, and tape up the edges so you don't cut yourself.
Duping setups are great for speed since they're mainly restricted by how quickly you can change out the artwork, but the quality will suffer here and there, especially if you don't have a nice macro lens. For ultimate quality, you'll still need a film scanner, but for speed and easy set up, a slide duper or copy stand is a great way to go.
Once you have your scanner or duping setup picked out and you've set up and installed the necessary software, it's time to get scanning. Before you begin though, take a little time to think about your workflow.
For my project, I wanted to have my entire film collection digitized with reasonably good preview images in Aperture. I wanted to be able to edit and organize my photos as if they were all digital originals. In fact, in some sense, I wanted the two collections to become one.
For this, I turned to Automator and the folder action I had set up in the Tethered Shooting with Aperture article. I was basically performing the same task, so why not reuse the setup? For the slides that I wanted to scan with the Nikon LS-4000, I set my scanning software (Nikon Scan) to save each file in a "hot folder." This meant that every time a new image was added to the folder, Automator would run, and the file would automatically get imported into Aperture. The Tethered Shooting setup can also come in really handy if you're working with a duping setup as mentioned above. For more information on how to set up a Hot Folder, see my previous article on Tethered Shooting here.