How does altitude affect camera and lenses?

Question

This summer I'll be attempting to get to the top of Kilimanjaro. I'm bringing my Olympus E-30 and a couple of lenses. The instructions I've received mentions that you should check the height range with the manufacturers of any digital equipment you're bringing.

Kilimanjaro is 5895 meters tall (19341 ft).

How, if at all, will the height affect my digital camera?

Answer

Nothing will be wrong with your digital camera.

However, do not use a Microdrive or any device which includes ones. Those have a 10,000 ft maximum altitude. Microdrives as Compact Flash are rare these days but they are commonly (but not always) used in video cameras, iPods and media-players.

Once on a press trip with 11 other photographers we reached an altitude of 12,000 feet and every single iPod in the group failed. A number of people were expecting to use those devices to off-load their data. I was surprised to find out I was the only one who know about the altitude problem.

NOTE: It is actually not the altitude that matters but the air-pressure that is necessary to lift the HDD head off the platter. Still, manufacturers quote altitude. Where it matters is on a plane. Commercial aircraft are pressurized around 85kpa (as measured by me) which corresponds to a much lower altitude (roughly around 6000 ft) than their corresponding cruising altitude, so you can use a Microdrive on most such aircrafts.

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