Doug Kerr
Well-known member
Often, we see one or the other of these pieces of advice regarding CF cards:
1. It is better when wishing to clear all image files from a CF card to reformat the card than to delete all the image files.
2. Even if not using reformat to clear the card, one should periodically reformat it retain best performance, possibly even to avert some misbehavior.
3. One should always reformat a new card in the camera in which it is to be used before actually using it for shots.
4. One should not use the same card first in one camera and then in another without reformatting it.
(There are clearly some overlaps among these axioms.)
Almost always when I see one or the other of these written, I invite the author to help me by explaining what actual technical phenomena are being averted by following it. The results have never been satisfying.
Among the responses I get are (I will give the key number of the pertinent recommendation in parentheses):
A. (1) Clearing all the files by reformatting is faster than by deleting all files. (Sometimes this is said in the context of doing it in the camera; other times, it is in the context of doing this with the card in a card reader, and of course various tools are discussed.)
B. (1) Clearing all the files by deletion vs. reformatting uses up more of the card's finite life of read-write cycles.
C. (1, 2) Doing this gets rid of file fragmentation, which will otherwise accumulate over time, and which can degrade the performance (notably write and/or read speed) of the card.
D. (3, 4) If you don't, you will expose yourselves to the possibilities of corrupting the card, losing files, or getting cooties. (Details of the actual presumed potential technical mechanisms for such are never forthcoming.)
My take on these has always been as follows for the different cases:
A. Yeah, probably, although I'm not really sure.
B. Yeah, I guess. I'm sure I'll wear out the connector long before.
C. Hard to believe. If we periodically clear all files from the disk (even by bulk deletion) of individual files, the FAT is all set to "available") (except for defective clusters), and presumably the O/S will then write each file added in contiguous clusters. And we don't normally "re-write" the same file. (I actually don't understand why even the presence of fragmentation on a static memory would cause performance degradation, but I understand that it will, although certainly not to the degree it would in a hard disk drive.)
D. My mother said that cooties were only a problem at the end of town were the factory was.
So, what can those of you who know more than I about mass storage management tell me about the reality here?
For my own part, I only once in my life ever reformatted a CF card, and that was for testing of the effect of different cluster sizes on the ability of a Fuji S602 to write "streaming video" to the card. I take new ones out of their blister packs and, after adding my "owner information" text file, bang 'em into the camera. I move them between cameras (normally cleaning off all the files and directory structures before I do, by deletion, to prevent folder and file numbering derangement).
The cootiephobes point out that my entire data recording life is on borrowed time and that God will strike me down as soon as He gets around to it.
A recent horror story (told on dpr, of course) is of a 5D that always writes corrupt .CR2 files. It is believed to be because it once was penetrated by an impure CF card.
Thanks, gang.
1. It is better when wishing to clear all image files from a CF card to reformat the card than to delete all the image files.
2. Even if not using reformat to clear the card, one should periodically reformat it retain best performance, possibly even to avert some misbehavior.
3. One should always reformat a new card in the camera in which it is to be used before actually using it for shots.
4. One should not use the same card first in one camera and then in another without reformatting it.
(There are clearly some overlaps among these axioms.)
Almost always when I see one or the other of these written, I invite the author to help me by explaining what actual technical phenomena are being averted by following it. The results have never been satisfying.
Among the responses I get are (I will give the key number of the pertinent recommendation in parentheses):
A. (1) Clearing all the files by reformatting is faster than by deleting all files. (Sometimes this is said in the context of doing it in the camera; other times, it is in the context of doing this with the card in a card reader, and of course various tools are discussed.)
B. (1) Clearing all the files by deletion vs. reformatting uses up more of the card's finite life of read-write cycles.
C. (1, 2) Doing this gets rid of file fragmentation, which will otherwise accumulate over time, and which can degrade the performance (notably write and/or read speed) of the card.
D. (3, 4) If you don't, you will expose yourselves to the possibilities of corrupting the card, losing files, or getting cooties. (Details of the actual presumed potential technical mechanisms for such are never forthcoming.)
My take on these has always been as follows for the different cases:
A. Yeah, probably, although I'm not really sure.
B. Yeah, I guess. I'm sure I'll wear out the connector long before.
C. Hard to believe. If we periodically clear all files from the disk (even by bulk deletion) of individual files, the FAT is all set to "available") (except for defective clusters), and presumably the O/S will then write each file added in contiguous clusters. And we don't normally "re-write" the same file. (I actually don't understand why even the presence of fragmentation on a static memory would cause performance degradation, but I understand that it will, although certainly not to the degree it would in a hard disk drive.)
D. My mother said that cooties were only a problem at the end of town were the factory was.
So, what can those of you who know more than I about mass storage management tell me about the reality here?
For my own part, I only once in my life ever reformatted a CF card, and that was for testing of the effect of different cluster sizes on the ability of a Fuji S602 to write "streaming video" to the card. I take new ones out of their blister packs and, after adding my "owner information" text file, bang 'em into the camera. I move them between cameras (normally cleaning off all the files and directory structures before I do, by deletion, to prevent folder and file numbering derangement).
The cootiephobes point out that my entire data recording life is on borrowed time and that God will strike me down as soon as He gets around to it.
A recent horror story (told on dpr, of course) is of a 5D that always writes corrupt .CR2 files. It is believed to be because it once was penetrated by an impure CF card.
Thanks, gang.
Last edited: