Hi,
A recent thread on the Support forum ("PM, Nikon D90, Windows 7 and Ingesting") brought up a something I'm curious about. Please let me quote some text from that thread:
...downloading is usually faster, and safer, with a card reader anyway...
(vs a direct cable connection to a camera)
My question is WHY is it safer?
I've heard/read this numerous times but I do not understand why. I tend to think the opposite.
I tend to think there is a greater risk in the camera not working if, through repeatedly removing/inserting the card, I were to damage the internal card<->camera contacts, than if I were to damage the external USB connection. I figure there would be a near 100% chance of camera failure if the internal card contacts are damaged or worn down (as the camera uses this connection for normal operation), and something less than 100% chance of camera failure if the external USB connection is damaged or worn down (e.g. perhaps I just lose the USB cable connect function). Does this go against conventional wisdom?
Now I understand that using a card reader gives (a) better speed and (b) allows use of PM's ingest capability direct from card (e.g. for cameras with no "mass storage" mode like D90), but I do not understand the "safer" argument.
Why is using a card reader safer?
Chris, as I was the one hinting at a card reader being more safe, I'll give you some reasoning for this statement.
The way I look at it (and this is something that is agreed upon by many), one of the design aspects of memory cards was their intended use, this includes inserting and ejecting them frequently. If you take a at an SD or CF card for instance, you can see how this design aspect is implemented.
An SD card has very large contacts. Inserting/ejecting them is easy and actually well guided; there is no way of bending anything without real force.
A CF card contains many more and uses pins to make the connection. This does sound fragile, but inserting a CF card is again guided, making it impossible to insert them wrongly without force. Ejecting a CF card from the camera is (usually/always?) done using an eject key which again makes it impossible to bend the contacts. So all in all, this again is a very robust and safe implementation. (Note: I have heard of and actually seen people with bent pins, but this was invariably after applying force when insert the card (wrongly), and/or with badly designed card readers where the CF card guides aren't "deep" enough).
Now take a look at the design of the camera USB connector, you can image it breaking off with only little force (the connector actually works as a lever) as everything is pretty fragile looking (much more so than the SD/CF card slot where the whole card is kept quite firmly)
Oh, and then I haven't even mentioned the fact that it is so easy to bump your camera off your (crowded) desk when off loading your images. If this happens, the connector inside the camera will almost definitely have broken off (perhaps even worse). A card reader is much smaller and lighter, and even if you bump this off your desk, it is highly unlikely anything bad happening.
So yes, using a card reader is safer (IMHO)