When I first set up my mediawiki (1.5beta4), I didn't have ImageMagick installed. I then decided to add that capability, downloading and installing the binaries for ImageMagick 5.5.7 (dynamic) and php_imagick.dll. Note that Imagick does not work with the static version or version 6 of ImageMagick (PHP5.0.4 complains that it cannot find the dll).
So having successfully loaded imagick and having tested imagemagick to check that it resizes images from the command line, I then made changes to the LocalSettings file. However, what I find now is that while mediawiki creates folders for resized images and creates links to the resized images in those directories, the resized images do not exist. Can anyone give me guidance on where to look for error messages (I am using IIS6>0 webserver). If you have already had this problem and solved it, then I would be even more interested in hearing from you.
Incidentally, as part of my search, I came across a program called MagickWand which has had a PHP dll written for it that looks as though it will be a replacement for Imagick (which works with ImageMagick 6), although I am not quite clear yet on how it would be implemented. I realize that this is principally of interest to people running mediawiki on Windows machines.
As always, any help would be much appreciated. Once I have this sorted out, I shouldn't need to ask any more questions! Thanks!