You have an open body cavity a foot or two from where you are standing, doctors and nurses surround and are hunched over the patient, their eyes seemingly shooting darts into you with the demand to take the shot, NOW! In particular, with cardiac patients, hearts visibly beating under the lights, I literally have seconds to take the shot(s). And these shots have to be well-exposed, in focus, and with very generous depth-of-field (which can be a challenge given the short shooting distance). There cannot be retakes/reshoots.
The equipment has to be light with ergonomics for the cramp space (mindful not to brush your scrubs against anything). Since it's next to impossible to use the viewfinder (this would necessitate leaning over the body cavity), I've come to rely on a flipping finder (so only the camera is over the body cavity) with my arms extended out. And when using a finder, i.e., Live View, I'll need to get in focus and maintain focus, fast!
Enter the Sony SLT camera, in this case, the a57 (could also use the a65, or the new a6000). The one thing these cameras have in common is their fast phase detect auto-focusing system using Live View. Small, light, and very inexpensive, these cameras also have flipping high resolution screens (and NOT articulated finders which make you view the scene away from the lens axis, e.g., Canon 70D). For my lens, I use a 30 year old Minolta 50f2.8 macro, which is as good as any modern macro for sharpness and chromatic aberration, and available on eBay or on Craigslist for $200 (mental note: buy the next one that comes up on craigslist for under $200). For my ring flash, I use the lightest, least expensive, and most power efficient (2 AAA's lasts a long time) flash available: the Metz 15 MS-1. It connects wirelessly, avoiding the cables and the flash body mounted on the hot shoe (see the Nikon with the Sigma flash, below).
Shown below are two setups used in the past that were the standard, until I "discovered" Sony's phase-detect Live View.
left: Nikon D90 with 120mm Medical-Nikkor and battery pack (6AA's)
right: Nikon D90, Micro-Nikkor 85f3.5, Sigma Ringflash (4AA's)
3 times the weight and volume of the Sony setup, primitive Live View, static LCD, manual focus
almost twice the weight of the Sony setup, top-heavy and awkward, static LCD with primitive first gen contrast detect autofocus. But this lens is very sharp! February 20th.