Microdrives

2006.05.13

Microdrives are perhaps the most controversial form of digital camera memory. For their capacity, they are extremely cheap but people worry that these miniature drives are not as solid as their solid-state counter-parts. No doubt, Microdrives are not as sturdy as flash memory due to moving parts and their holow structure. Nethertheless, these drives can take the place of flash memory quite successfully.

Experiences vary, with some people experiencing problems and some people completely satisfied. Note that some people also reported problems with poor quality flash memory cards as well. Having acquired a 1 GB IBM Microdrive 4 years ago and a 6 GB Hitachi Microdive last year, I count myself among satisfied Microdrive owners.

The only certain disadvantage of Microdrives is their altitude limit. According to the specifications on the IBM Microdrive, it has a maximum operating altitude of 10,000 ft. Some people never wander past that limit, but there are many beautiful places which can be photographed passed that altitude. Since I've been at those altitudes several times, I was curious if the Hitachi Microdrive has the same altitude limit. Strangely, there was no mention of operating altitude in the specification of the 6 GB Hitachi microdrive. Not being certain whether this was an omission or not, I contacted Hitachi support. A few days later, I got the following very clear answer:

Thank you for contacting Hitachi Global Storage Technologies.

Microdrives like all hard disk drives do require a certain amount of air pressure to work correctly. The Hitachi drives are designed to run at between an altitude of "300 meters ("1,000 ft) to an altitude of 3048 meters (10,000 ft).

The specification is set by the allowable spacing between the head and disk. The 'fly height' of the head above the disk is determined by the number of air molecules available to provide lift on the air bearing features. At extreme low altitudes, there will be too many molecules so fly height will be high and head signal strength will decrease resulting in poor performance. At extremely high altitudes, there will be too few molecules and there may be mechanical contact between head and media.

Please let us know if we can be of further assistance.

Well, it could not be clearer: Hitachi Microdrives are still limited to 10,000 ft of altitude. Despite their limitations, the current prices of Microdrives are hard to ignore. Last week, Tiger Direct had an 8 GB Microdrive for 203 CDN (182 USD). An 8 GB Compact Flash solid-state memory card, on the other hand,went for 458 CDN (410 USD), giving Microdrives a clear advantage in price. Since solid-state memory has no operating altitude limit and are available in much higher speeds, there are defintely reasons to get those too.

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