Sony – Sony makes fine camera, especially their mirrorless camera bodies, which could be very useful for photomicrography and macro work.
Extreme Macro is an exhaustive Internet resource for techniques in macrophotography. While this site is mainly devoted to entomological subjects, the techniques are applicable to geologic subjects as well. This site is maintained by Johan J. Ingles-Le Nobel.
Helicon Focus – This is a great and widely used program for stacking photograph images. Helicon has add-ons that work with StackShot focusing rail hardware to automate the stacking photograph process.
Photomatix – Not for everyone, high-dynamic range (HDR) photography techniques solves the problems of extreme contrast in photographic scenes. Mastered, this technique produces amazing results. Use judiciously, though.
Stackshot focusing rail – Made by Cognisys, the Stackshot focus rail is an automated rail for stacking photography.
Zyrene Stacker – Another fantastic stacking software package for processing stacked images.