Portable document scanner, where to start
Where portable scanners drop the ball a bit is with regard to the quality of the image. As useful and convenient as these devices are, they simply can't compare with larger models in terms of the clarity of the image. Nevertheless, they are sufficient for most casual uses, and their small size and portability makes up for any deficiency in image resolution. If you do want to get a better quality image, check for the dots per inch or dpi of the particular portable scanner that you are considering. If you intend to be doing a lot of photo scanning and want to resulting images of sufficiently high quality, you will want to get a portable scanner that offers 48 bit depth.