My primary photographic setup is a bellows based system. This gives me the most flexibility to image a variety of different sized coins in the highest resolution possible. My equipment is described below.
I shoot with a Canon T2i digital single lens reflex (DSLR) camera body. The camera has a 17.9 Megapixel APS-C sized CMOS sensor (22.3 x 14.9 mm, 5184 x 3456 pixels). Images are captured using a wireless remote shutter release, a 2-second timer delay, and with the camera mounted on a copy stand to ensure the sharpest image quality.
My primary bellows is a single-rail dovetail precision system manufactured in Japan by Asahi Optical Co. Limited (now known as PENTAX), and imported and sold in the USA by Honeywell as the Pentax Autobellows. It has M42 universal mounting threads at each end.
I use a variety of lenses depending on the need. Most of my lenses are enlarging lenses or duplicating lenses mounted to my bellows system using a simple M39 to M42 mounting threads adapter. My primary full-coin lens is a 6-element APO-Rodagon-D 75mm f/4 duplicating lens, optimized for flat field work and exhibiting superbly sharp detail.
I use primarily LED lighting for full-coin images, with custom adjustment for white balance performed after any changes in camera settings or lenses. To bring out both luster and tone, I use a combination of direct and diffuse light depending on the metal composition of the coin and the extent of toning. I also occasionally use axial lighting for toned or proof coins, to highlight the surfaces and colors. My ultimate goal is to accurately represent the coin digitally as closely as possible to its appearance in hand.