giordano Posted January 20, 2011 Share #21 Posted January 20, 2011 Advertisement (gone after registration) It also must write an empty root directory; otherwise everyone would be extremely unhappy about file entries pointing to reclaimed free space. You're right. I'd assumed that a quick format simply marked everything in the root directory as deleted, but investigation shows that a quick format zeros (at least the first cluster of) it. Link to post Share on other sites More sharing options...
Advertisement Posted January 20, 2011 Posted January 20, 2011 Hi giordano, Take a look here SD Card Formatting. I'm sure you'll find what you were looking for!
mjh Posted January 20, 2011 Share #22 Posted January 20, 2011 I'd assumed that a quick format simply marked everything in the root directory as deleted, but investigation shows that a quick format zeros (at least the first cluster of) it. Probably because the latter is faster. Of course all the image data is still intact even after a quick format, and maybe large parts of the directory as well. Who cares about directory entries pointing to free space when those entries will never be accessed. Link to post Share on other sites More sharing options...
dewittehd Posted January 20, 2011 Share #23 Posted January 20, 2011 How many times does one re-format the hard disk on one's computer? Or a floppy (what's that again?). Or a RW-CD? Why should a storage card be different? In my 10 years of digital I have never reformatted a card, and I have lost exactly zero images. :-) Jean Link to post Share on other sites More sharing options...
250swb Posted January 20, 2011 Share #24 Posted January 20, 2011 How many times does one re-format the hard disk on one's computer? Or a floppy (what's that again?). Or a RW-CD? Why should a storage card be different? In my 10 years of digital I have never reformatted a card, and I have lost exactly zero images. :-)Jean Could it just be that you don't want to delete everything off your PC hard disk as you do with an SD card? As regards ten years of successfully saving images, its rather like the driver who says while being carried off after an accident 'but I've driven around that corner every day for ten years on the wrong side of the road so I don't understand why I hit another car now'. Its not a way of life to copy. Steve Link to post Share on other sites More sharing options...
mjh Posted January 21, 2011 Share #25 Posted January 21, 2011 As regards ten years of successfully saving images, its rather like the driver who says while being carried off after an accident 'but I've driven around that corner every day for ten years on the wrong side of the road so I don't understand why I hit another car now'. The superstition about regularly formatting cards for some supposed benefit reminds me of the joke about the man walking down the street, clapping his hands every ten seconds. When asked why he does this, he explains: “To drive away the elephants.” “But there are no elephants here!?” “You see? It works!” Link to post Share on other sites More sharing options...
pop Posted January 21, 2011 Share #26 Posted January 21, 2011 You're right. I'd assumed that a quick format simply marked everything in the root directory as deleted, but investigation shows that a quick format zeros (at least the first cluster of) it. That's what is commonly understood by "formating" a device, placing an empty file system structure on the medium. In the case of the FAT file system, it mainly consists of the FAT and the root directory being reset to indicate an empty medium. As you and others have pointed out, the contents of the files still reside on the medium until you start writing new stuff to the medium. It will then be overwritten by the new data. In terms of writing operations a quick format tends to be faster than erasing a number of files, even if erasing the files just consists of marking their entries in the directory as "deleted". The reason why I personally choose to delete files rather than to format the card is twofold: (1) Deleting requires fewer manipulations on the PC; my OS prompts me to empty the garbage bin after moving the files from the card to the computer. (2) I use my cards in several cameras and even in my mobile phone. I don't trust any of those devices to do it properly, so I don't format in-camera if I can help it. However, at the first sign of trouble the card gets thoroughly reformatted, and not by any quick formats. I also carry a spare one in my purse, even when I don't happen to have a digital camera with me. Link to post Share on other sites More sharing options...
k-hawinkler Posted January 23, 2011 Share #27 Posted January 23, 2011 Advertisement (gone after registration) From M9 Instructions: "Formatting the memory card It is not normally necessary to format (initialize) a memory card that has already been used. However, if a card that has yet to be formatted is inserted for the first time, it muss be formatted. In such cases the Format SD card sub-menu appears automatically. The LEICA M9 allows you to select whether you only want to format the memory card or to actually completely delete all data on the card, e.g. to protect against misuse, by overwriting. Notes: • Simple formatting does not irretrievably delete the data on the card. It merely deletes the directory, which means that the existing data is no longer directly accessible. The data can be accessed again using appropriate software. Only the data that is then overwritten by saving new data is actually completely deleted. Nevertheless, you should get into the habit of transferring all your pictures onto a secure bulk storage medium, e.g. the hard drive on your computer, as soon as possible. • Depending on the type of memory card being used, formatting may take up to 2 minutes. • Depending on the capacity and read/write speed of the card, overwriting can take up to 60 minutes." I never format a memory card in my Mac. I find formatting regular memory cards without overwriting in the camera a fast and easy way to get back to a defined state for the memory card. Having played with Eye-Fi memory cards a bit in the M9 as well, one finds that extra information is stored on the card that's not visible if one checks image files in the camera. The Eye-Fi card comes with (old) software installed on the card. It also stores there wi-fi information it needs to transmit the images to the correct computer, iPad, iPhone, etc. I used one Eye-Fi card on several different cameras, namely M9, D40, D3, D300. As I didn't want to format this particular card, I deleted image directories from different cameras on it on the Mac and, of course, then emptied the trash. Images that have been stored, say by the D40, don't seem to be visible in the M9 and can't be deleted by the M9, but I would think can be effectively dealt with by formatting. I haven't yet tried out what happens when I format the Eye-Fi card in the camera. My suspicion is I also would lose files other than images that I still need. K-H. Link to post Share on other sites More sharing options...
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