In the last post, I talked about scanning using desktop flat-bed scanners. There are alternatives. Camera technology has increased to the point where, in some instances, cameras can do the same job or better than a flat-bed scanner. This is particularly true with the higher resolution digital cameras that are now readily available.
The resolution of digital cameras is measured in pixels. Up to a point, the more the better. Over the past few years the resolution of digital cameras has steadily increased, the average low priced (under $300) camera will take very high resolution pictures. Cameras starting at below $100 have 7.0 Megapixel resolution. One Megapixel is a resolution of one million pixels. The higher the number, roughly speaking, the higher the resolution of the camera. However, cameras priced at the low end, have fairly cheap optics or lenses. In today's market (2008) higher end cameras, around $1000, have from 12 to 15 Megapixels. The number of Megapixels is also roughly comparable to the number of sensor units in the camera. The present upper limit is about 144 megapixels.
I have found that 10.1 Megapixel cameras take photos that are as detailed as scans from a flatbed scanner for documents and printed materials. However, for photos, you can still get a better image from a flatbed scanner. If you have a lot of family letters to scan, I might suggest using your camera on a tripod or other stand. Taking photos of the pages is tremendously faster than scanning and the resolution, if over 10 Megapixels, is comparable. If you have a camera already, you might try a few photos of documents to see if the resolution is acceptable or not.
Off the subject a little, you can take your camera to the library or other record repository and if the rules allow, take pictures of the pages of the book you are citing. Don't forget to take a picture of the title page and call number. Since there is no film involved, the pictures saved to your hard drive are certainly cheaper than paying for poor quality photocopies. You can also attach a copy of the document to your file for reference. (More on this technique later).
You can also use your digital camera to take pictures of actual physical objects, i.e. dolls, jewelry, guns, etc. The pictures can then be attached to your file to illustrate a family history.
Slides are a different matter. A lot of scanners sold today advertise that they can also scan slides. This is literally true, but the quality is really poor. I have yet to see a flatbed scanner produce an acceptable scan of a 35mm slide. To do slides, you should use a scanning service or, if you have a whole lot of slides, buy a dedicated slide scanner. Unfortunately, these devices are not cheap. Nikon makes a very good slide scanner called the CoolScan but it costs over $1000. If you read a lot of reviews, you will soon discover that this is about what it costs to get an adequate scan of a slide.