Compact Flash versus Micro Drives
Having written an article recently about how to carry your memory cards in the field, it seemed a good opportunity to touch on the age old question of compact flash versus microdrives.
For those unfamiliar with them, microdrives are tiny, spinning hard disc drives fit into the one-inch form factor of a Type II compact flash card. Compared to the hard drives found in desktop and laptop computers, microdrives are truly engineering marvels to behold. I mean, they're just so small.
In the early days of digital photography, compact flash cards were expensive and many users were tempted by the lure of microdrives which tended to cost less per megabyte. But the ever since they were first introduced by IBM back in the 1990's, there have been questions about their reliability.
Unlike a compact flash card which is a solid state device, a microdrive is comparatively fragile if dropped. While actually using it, you are unlikely to have a problem since most people tend to be fairly gentle on the cameras. It's once you take a microdrive out of your camera that the chance of a mishap increases. You are much more likely to drop the card than your camera. Or at least I hope so.
But if you drop a microdrive on a hard surface, you can damage its read/write heads, and if you do, its toast. Shock damage can cause you to lose all the images you shot on it if you aren't careful. I don't want to give the impression that such accidents are common — they're not. But if this happens to you, it doesn't matter how few other people it may have happened to. And it does happen. Studio shooters may be able to use microdrives without any problem, but nature photographers work outdoors where conditions are less predictable and gear has to be able to take at least some abuse. For this reason, I've stuck with compact flash cards since I started shooting digitally.
In order to spin their platters, microdrives also use up more battery power to operate than do compact flash cards. They also tend to have slower transfer rates since they have mechanical moving parts inside them. Both of these are real problems, but minor in compared to the issue of reliability.
Prices for compact flash cards have come down so much that there's less talk of microdrives these days, but in addition to the war on prices, there is also a healthy competition on card sizes. Hitachi who bought the original microdrive technology from IBM in 2002 has plans to introduce a 20 GB microdrive in the near future, so the temptation won't die off any time soon. Just be sure to give some thought to what will work best for you before you give in to that temptation.