Image de-warping tool, and Multics/GCOS panels

Hey all, I've been doing research on Multics front panels, which it turns out are slightly different from those on the Honeywell 6000 series machines which ran GCOS, and are often confused with them. So, I've put together a Web page about them: Multics and Related 6000 Series Front Panels http://ana-3.lcs.mit.edu/~jnc/tech/multics/MulticsPanels.html and I've taken some new images, so make sure the captions are all readable. I'm having an issue with the images, though: taking a picture of a flat, rectangular panel with a camera usually produces distortion (even with the lens set to the narrowest angle possible). Does anyone know of any freeware which will fix this? The image tool I normally use (ImagePals, sort of a poor man's Photoshop) does have a 'warp' function, but it requires setting up a grid of points, and is a pain to use: optimal would be something where you mark the 4 corners, and few intermediate edge points, and the image is automagically fixed. I did find this: http://guides.library.illinois.edu/c.php?g=347882&p=2345440 but it's even hairier than the warp function in my image tool; it's very powerful (and thus complex, sigh) and can straigten out badly warped old book pages. I'm hoping there's a simpler tool, for the simple case of distortion of rectangles by a lens - does anyone know of anything? Thanks! Noel