The photos were taken with:
Various 35mm cameras and Kodachrome 64 transparancy film.
Minolta X-300 camera and Fujichrome or Fuji Sensia 100 transparancy film.
Mamiya 645 camera and Fuji Provia 100 or 100F transparency film.
Canon EOS-300D camera with EF-S 18-55mm lens (until April 2004).
Canon EOS-300D camera with Tamron SP AF 28-75mm XR Di (May 2004 to April 2006).
Canon EOS-350D camera with Tamron SP AF 28-75mm XR Di (May 2006 to October 2006).
Canon EOS-350D camera with Canon 24-105L (November 2006 - September 2008).
Canon EOS-350D camera with Canon 24-105L or 70-200L (September 2008 - December 2009).
Canon G11 compact camera (December 2009 - December 2013). I didn't acquire this camera for shooting trains, but it proved to be perfectly capable in most situations. The biggest problem was lack of dynamic range in contrasty light, and noise in low light situations. Otherwise it was fine.
Canon G1X compact camera (December 2013 onwards). This is basically a Powershot G-series camera (like the G11) with a DSLR sensor - specifically a slightly smaller version of the sensor used in the Canon 7D. In essence, all the advantages and disadvantages of a G-series compact, but with DSLR image quality.
In most cases the Fuji film was processed by Fuji (at Leamington). The K64 was processed by Kodak of course.
The 645 transparencies were scanned using an Epson 3200 flatbed scanner and the 35mm transparencies ones with a Minolta Scan Dual III.
RAW conversion of the digital images was mostly done with Adobe Camera Raw, as built into Photoshop Elements, or Canon's DPP software for some of the images taken with the G11. Post-processing of images was mostly done with various versions of Photoshop Elements.
It's been many years since it was possible to park yourself near any reasonably busy British railway line and be fairly certain that something interesting would pass by - unless multiple-units are your thing (and they're not mine). These days the good stuff is so thin on the ground that you need to know where it is. So here I should take a moment to express my thanks to various friends and acquaintances who share information when they have it, and also to the posters on various railway gen lists for their generosity. Access to good information is at least as important as cameras and software, and probably more so, when trying to take the sort of photographs found on this site. So thanks again to all who have helped, knowingly or not.