> But > formatting may (although it's no guarantee) repair a glitch in an iffy > card and let you continue using it. > > -bmw
Some facts and common sense: SD memory is NAND flash which means the following things: 1) manufacturers ship it with errors already on the chip; 2) it deteriorates over time (with write/delete cycles); 3) it contains software and hardware to detect new errors on the fly and record information about the bad blocks; 4) said software isolates the card from the outside world - no program writes directly to the free space on the card. What formatting these does should be exactly nothing (or equivalent to deleting files) but formatting is done with a piece of software on the host computer (or camera) and therefore can introduce more writes/deletes than necessary. What people formatting cards usually think is that the whole card will be writeen full of zeros - which - although thankfully not the case - is actually what you don't want to do - ever (because of the wear and tear). Now whether cards become bad with time or not is mostly dependant on the hardware/software controller on the card itself - depending on how good it is at choosing places to write files and how good it is at marking the bad spots on the card - the card could either die very fast or live practically forever. So what card you buy really matters. Usage - whether you write large volumes of data or routinely "format" the card with a formatting tool that comes with your operating system and was never intended for formatting flash memory - comes second. With luck the controller on the card can deal with your formatting tool and fool it into thinking that the card has been formatted - although if we look at an empty card that you are formatting to the same file system it already has and with the same options, there should be no writes at all. So what this all comes down to is: if it aint broken, don't fix it. If it breaks, pray to god that you can actually do anything about it - chances are you can't - at least formatting can only stumble upon errors in a very limited space at the beginning of the card - and is very much like a blind man trying to walk into the only tree that's in the middle of a very large field. kris -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.