A very good compact personal scanner

I bought this scanner to replace an older parallel port model. I like that it's very compact, and requires only a single USB connection for both power and data. You can even stand it on its side with the help of a little plastic stand that's included with the scanner, but it's not easy to use in that position - I prefer to store it in the vertical position and just lay it flat on my desk when I want to use it.

Scans of both documents and photos look great with the default settings. There are no apparent streaks or scan lines or any other defects. Color balance and contrast look good. The resolution is more than adequate for me at 600 x 1200 dpi. I can't imagine why anyone would want to scan documents or photos at resolutions greater than 600 dpi. A scan at that resolution generates an enormous file, and it's already fine enough to capture the grain in photo prints and the dots in printed documents. Software interpolation to higher resolutions is even sillier. The only possible reason to want a higher resolution would be for scanning film or slides, and this scanner doesn't have a film or slide holder.

As for speed, it's no speed demon, but it's fast enough - certainly faster than my old parallel port scanner. The connection is USB 1.1. A preview takes about 15 seconds, a monochrome document page or a 4 x 6 inch color photo at 300 dpi about 30 seconds, a photo at maximum resolution about 2 minutes. I wouldn't do a lot of bulk scanning with it, but for personal scanning it doesn't seem slow.

The scanner needs about 60 seconds for calibration when you first connect it. After that it seems to initialize in a few seconds when you first access it. It uses an LED light source that doesn't need to warm up. The computer is not locked up while it's scanning. It makes a bit of a whining noise when doing a fast scan or returning the scan head to the home position, but it's nothing too loud or obtrusive. I wish it had a couple of indicator lights on it, something like a Ready light and a Scanning light, but there's nothing. No power switch either. I guess it's not really necessary.

I should mention that although the scan surface glass appears to be 12 inches long, the scanner will only scan 11.69". That's enough for A4 paper, but not enough to scan four 4x6" photos at once.

Another minor problem I have noticed over time is that dust specks on photos are emphasized more than normal with this scanner. I think this may be a side effect of the lighting geometry forced by the thin case design. Perhaps the LED lighting is placed such that the light strikes the surface more from the side and is more directional than with a traditional cold-cathode lamp design, where the case is deeper and the light source is further from the scanning surface and more diffused.

In Windows the LIDE 20 appears as a TWAIN device in any photo or paint program. Canon's pop-up Scangear TWAIN software provides the usual preview window for selecting the specific scan area, and controls over resolution, color depth, and other adjustments. It has a "Simple" mode and an "Advanced" mode to make things easier for novices. Canon also installs a control-panel app in the "Scanners and Cameras" section in WinXP, but frankly it appears to serve no useful function other than to load yet another 3.1 Mbyte application into memory which sits around doing nothing all the time. I removed it with no ill effects.

Canon includes a pop-up program to respond to the 3 buttons on the front of the scanner, which are labeled Scan, Copy, and Email. While this type of thing is standard on most scanners these days, it's not very useful, and I removed it after a quick test. It's just another program sitting around in memory all the time doing nothing. I can copy a scanned image to the printer or into an email message without help, thanks.

Canon's Scangear TWAIN scanning software automatically applies color correction in photo scan mode. It usually works fine with photos that have a bit of a color cast, although of course it can be fooled by photos that are predominantly one color. It can be turned off if necessary. Scangear also applies an Unsharp Mask filter by default to sharpen up scans. The filter can also be turned off if you prefer.

Unfortunately the auto-rotation feature which attempts to straighten out crooked photos can't be disabled. It frequently malfunctions when multiple photos are scanned in one pass. This has been a known fault with Canon's Scangear software for over two years, and it still isn't corrected. It makes the theoretical capability to automatically scan multiple separate photos in one pass a bit useless.

Canon includes a couple of photo editing and photo management programs from ArcSoft on the installation CD. Better than nothing, but ArcSoft's software is not very advanced. The Adobe PhotoDeluxe software included with many other scanners is better. Canon's gear is fine, but I wish they would dump ArcSoft as their supplier of utility programs.

Oh, and the OCR program Omipage is included for converting scanned documents to text. It works about as well as these things usually do - adequate in ideal conditions, not usually practical.

A USB cable is included, which is more than Canon include with their printers!

There's a printed Quickstart guide in umpteen languages. The rest is on CD, but it's superficial at best - don't expect to find any answers to difficult questions there.

Canon's online support is usually good, but it could be better in the case of the LIDE 20. The "latest version" driver posted on the Canon USA web site is a year out of date compared to the one which came on the installation CD with the scanner.