Someone advised me to allways reformat a compact flash card after downloading all pictures. Supposedly jsut deleting the images may result in some kind of errors. I need to know what to do because my wife recently bought me a nice camera and i dont want to mess up the memory card. Does any body know??
memory cards??
- Thread starter Oilpants
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reformatting cleans the memory out completely, just deleting leaves some junk behind. I've never experienced any errors.
Pandabear is the real expert here, but I thought that periodic reformatting was most beneficial on magnetic media. I wouldn't think I'd do it every time, but perhaps every third or fourth. I'm curious to see what Panda says.
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I reformat with it in the carmera. I heard that is better than doing it with the computer.
I am probably wrong, so I would like to know what's best?
I am probably wrong, so I would like to know what's best?
Formatting does not really erase any data either. It just cleans out the table that shows where files are at. Not really any better than just deleting. For long life you want to reduce the number of writes on flash media. Erasing == writing.
Originally Posted By: Onmo'Eegusee
Formatting does not really erase any data either. It just cleans out the table that shows where files are at. Not really any better than just deleting. For long life you want to reduce the number of writes on flash media. Erasing == writing.
Exactly, formatting doesn't do bupkes for erasing the actual data, it just unlinks the files from the allocation table. While flash media does have a limited number of writes, I suspect that most of us would never even approach those limits unless the drive were being used as a swap partition or to store logs on a busy server.
So the short answer is: just delete the files and forget about the extra format step.
Formatting does not really erase any data either. It just cleans out the table that shows where files are at. Not really any better than just deleting. For long life you want to reduce the number of writes on flash media. Erasing == writing.
Exactly, formatting doesn't do bupkes for erasing the actual data, it just unlinks the files from the allocation table. While flash media does have a limited number of writes, I suspect that most of us would never even approach those limits unless the drive were being used as a swap partition or to store logs on a busy server.
So the short answer is: just delete the files and forget about the extra format step.
Junk does get left behind, it's just that cards now are so big that we don't notice. I don't know what that junk is but after you've deleted a few hundred photos, then do a format you'll see a difference in memory. Maybe it's different for different types of memory, my experience is with CF.
Canon recommends formatting in the camera.
Canon recommends formatting in the camera.
There are several types of "format" out there, and depends on which type you talk about, the result could be different:
1) Erasing and recreating the file system, but leave the data intact, aka quick format
This type of format basically leave everything behind, but wipe out the possible corrupted portion of the FAT table assuming that you are using FAT32 for your memory card. You will have less chances of fragmented files and therefore in case anything happens (like running out of battery, the camera firmware crashes, etc), the chances of losing your photo is smaller. You get this type of format if you do it on your Windows PC and check the quick format box.
2) Wiping the entire card out with a bunch of blank sectors
This is on top of the format mentioned above. It really doesn't achieve much more in terms of the health of the card compare to above. If the card's internal design will replace writing zeros with NAND block erase command, then you may be getting faster write performance next time around. For SanDisk card, we do not replace continuous write zeros with erase block (sizes up to 4MB each), but at least the partially written fragment internal to the flash memory could be consolidated (garbage collect) and makes the next time you write/read the card faster. The down side is this type of format will reduce the life of the card.
3) SD/MS specific erase card command
This is the one I think most people are talking about. Some camera uses this command when receive a "format" and wipe the card out very quickly, and really just leave the card in an entirely erased state. It will wear out the card by a little
but not as much as writing zeros to the card.
In terms of wearing out the card:
Not a big deal for most, but in the near future, when they were talking about using 3 bit per cell rather than 2 bit per cell, the life of a card goes way down, to something in the scale of 100-500 cycles per cell at the moment, before wear leveling. If you format, the entire card is written / erased so wear leveling won't help.
Personal opinion:
I do it on a regular basis so that the file system fragmentation is minimum. Most of the lost file problem I see is fragmentation in combination with low power / camera firmware bug related, so keeping a clean card reduces the possibility. However, there is probably no benefit or loss if you download your photos on a regular basis.
1) Erasing and recreating the file system, but leave the data intact, aka quick format
This type of format basically leave everything behind, but wipe out the possible corrupted portion of the FAT table assuming that you are using FAT32 for your memory card. You will have less chances of fragmented files and therefore in case anything happens (like running out of battery, the camera firmware crashes, etc), the chances of losing your photo is smaller. You get this type of format if you do it on your Windows PC and check the quick format box.
2) Wiping the entire card out with a bunch of blank sectors
This is on top of the format mentioned above. It really doesn't achieve much more in terms of the health of the card compare to above. If the card's internal design will replace writing zeros with NAND block erase command, then you may be getting faster write performance next time around. For SanDisk card, we do not replace continuous write zeros with erase block (sizes up to 4MB each), but at least the partially written fragment internal to the flash memory could be consolidated (garbage collect) and makes the next time you write/read the card faster. The down side is this type of format will reduce the life of the card.
3) SD/MS specific erase card command
This is the one I think most people are talking about. Some camera uses this command when receive a "format" and wipe the card out very quickly, and really just leave the card in an entirely erased state. It will wear out the card by a little
but not as much as writing zeros to the card.
In terms of wearing out the card:
Not a big deal for most, but in the near future, when they were talking about using 3 bit per cell rather than 2 bit per cell, the life of a card goes way down, to something in the scale of 100-500 cycles per cell at the moment, before wear leveling. If you format, the entire card is written / erased so wear leveling won't help.
Personal opinion:
I do it on a regular basis so that the file system fragmentation is minimum. Most of the lost file problem I see is fragmentation in combination with low power / camera firmware bug related, so keeping a clean card reduces the possibility. However, there is probably no benefit or loss if you download your photos on a regular basis.
Originally Posted By: tom slick
I don't know what that junk is but after you've deleted a few hundred photos, then do a format you'll see a difference in memory.
Do you mean a difference in size? If so, that's something to worry about (blocks get worn out and reallocated, shouldn't happen).
Quote:
Canon recommends formatting in the camera.
For a camera's perspective, it is always best to start with the same file system layout every time. There are odd cases when files were scattered and fragmented in various combination that the camera company may not have tested for, and therefore may have hidden bugs in the file system access code.
I got a card full of wedding photos from my friend. A Sandisk card that she said have lost the first half of the wedding's photos. I took the card in and use our in house diagnostic tool to check the card's condition: perfectly fine with no worn out blocks. Then I use a free file system recovery tool off the Internet to check the file system condition: the camera, or the HP printer she in her attempt to recover the photos, had a hiccup with the FAT table and retried writing the same file 100 times and overwrote all the previous files' FAT entry as well as the sectors that the files were located on. That's about 500MB worth of data wiped out.
A card does not operate on a file system basis and therefore the only conclusion is the Camera (a Canon or Nikon DSLR) or the HP printer has firmware bug. A reformatted card may not eliminate this, but the chances of stepping on these bugs would be greatly reduced if you start from a safe and known state every single time.
I don't know what that junk is but after you've deleted a few hundred photos, then do a format you'll see a difference in memory.
Do you mean a difference in size? If so, that's something to worry about (blocks get worn out and reallocated, shouldn't happen).
Quote:
Canon recommends formatting in the camera.
For a camera's perspective, it is always best to start with the same file system layout every time. There are odd cases when files were scattered and fragmented in various combination that the camera company may not have tested for, and therefore may have hidden bugs in the file system access code.
I got a card full of wedding photos from my friend. A Sandisk card that she said have lost the first half of the wedding's photos. I took the card in and use our in house diagnostic tool to check the card's condition: perfectly fine with no worn out blocks. Then I use a free file system recovery tool off the Internet to check the file system condition: the camera, or the HP printer she in her attempt to recover the photos, had a hiccup with the FAT table and retried writing the same file 100 times and overwrote all the previous files' FAT entry as well as the sectors that the files were located on. That's about 500MB worth of data wiped out.
A card does not operate on a file system basis and therefore the only conclusion is the Camera (a Canon or Nikon DSLR) or the HP printer has firmware bug. A reformatted card may not eliminate this, but the chances of stepping on these bugs would be greatly reduced if you start from a safe and known state every single time.
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Allright thanks!!! Im somewhat confused though. As I understand it formatting does not really erase the data it just doesn't allow the data to be found. Eventually the existing data may be over written. Formatting can help elimante bugs from the card. Because formatting counts as writting does formatting reduce the lifespan of the card? Also lets say i took a private picture of my wife and i delete this picture from the card. If I go to Walgreen's and give them the card to make prints can they possibly find the deleted Private pictures of my wife!!? Not that those would ever be dirty images but private nevertehless!!
There are two types of formatting: quick and full.
With the quick, you're just erasing the file allocation table, so that the operating system does not know where to find the files. It's kind of like removing the table of contents from a book. It makes it tough to find what you're looking for, but not impossible. So, a skilled computer nerd can theoretically recover such data, unless it has been already overwritten with new data.
If you do full format, you are actually erasing not just the file allocation table but also all data.
Not sure if this concept applies to flash memory, but I think it does.
With the quick, you're just erasing the file allocation table, so that the operating system does not know where to find the files. It's kind of like removing the table of contents from a book. It makes it tough to find what you're looking for, but not impossible. So, a skilled computer nerd can theoretically recover such data, unless it has been already overwritten with new data.
If you do full format, you are actually erasing not just the file allocation table but also all data.
Not sure if this concept applies to flash memory, but I think it does.
How do I do full formatting?? The manuel doesnt say what kind of formatting the camera is doing? Can I do it on the computer and if so what software do I need?? Thanks!!!!
I don't know what kind of format the camera does.
But if you have the card in the computer, just right-click on its letter (in "My Computer" if you're using Windows) and choose "Format..." It'll give you an option whether you want to do quick format. If you don't select quick format, it'll do full format.
But if you have the card in the computer, just right-click on its letter (in "My Computer" if you're using Windows) and choose "Format..." It'll give you an option whether you want to do quick format. If you don't select quick format, it'll do full format.
That worked!!! Thanks Qauttro Pete i can sleep better now that i know my wife isnt going to be OUT THERE!!
Originally Posted By: Quattro Pete
There are two types of formatting: quick and full.
With the quick, you're just erasing the file allocation table, so that the operating system does not know where to find the files. It's kind of like removing the table of contents from a book. It makes it tough to find what you're looking for, but not impossible. So, a skilled computer nerd can theoretically recover such data, unless it has been already overwritten with new data.
If you do full format, you are actually erasing not just the file allocation table but also all data.
Not sure if this concept applies to flash memory, but I think it does.
Flash memory (more specifically, flash memory card that is accessed on a sector basis) does not know anything about file system. You can say it is a blank piece of paper.
Format is a process of laying out the file system on a storage device. It is like laying out the lines and punching holes on a piece of paper you use.
When you write a file, in addition to writing the content of the file to the storage (i.e. the paper), it puts down a path on how to find the file, or pieces of the file if it is fragmented.
Quick format erase all the links, so you couldn't find the written files.
Full format wipe the links and the zero out the file contents, so you couldn't recover them, and the write process will expose any bad sectors.
Flash memory works the same as above, but the memory card's interface (i.e. SD and MS, for example) have additional commands that if used, will wipe out the entire card in one shot, rather than writing zeros to each sector, then garbage collect, then having to erase the sectors next time when you write it. The reason for all the additional work of writing zero and erase is that flash memory has an additional state outside zero and one, called erased. If you write all zeros or all ones to the sector, it needs to be erased before you can write it again. So it is more efficient to erase when you want to just blank it out. So the firmware does not have to zero it out next time around.
After wiping out the contents, then some initial values (FAT table, etc) are written to define the file system (the official format). It is up to the camera manufacture to decide whether to zero out the card or to use the card's erase card command when wiping out the original content before use. All I can say is even I wouldn't know which camera uses what.
There are two types of formatting: quick and full.
With the quick, you're just erasing the file allocation table, so that the operating system does not know where to find the files. It's kind of like removing the table of contents from a book. It makes it tough to find what you're looking for, but not impossible. So, a skilled computer nerd can theoretically recover such data, unless it has been already overwritten with new data.
If you do full format, you are actually erasing not just the file allocation table but also all data.
Not sure if this concept applies to flash memory, but I think it does.
Flash memory (more specifically, flash memory card that is accessed on a sector basis) does not know anything about file system. You can say it is a blank piece of paper.
Format is a process of laying out the file system on a storage device. It is like laying out the lines and punching holes on a piece of paper you use.
When you write a file, in addition to writing the content of the file to the storage (i.e. the paper), it puts down a path on how to find the file, or pieces of the file if it is fragmented.
Quick format erase all the links, so you couldn't find the written files.
Full format wipe the links and the zero out the file contents, so you couldn't recover them, and the write process will expose any bad sectors.
Flash memory works the same as above, but the memory card's interface (i.e. SD and MS, for example) have additional commands that if used, will wipe out the entire card in one shot, rather than writing zeros to each sector, then garbage collect, then having to erase the sectors next time when you write it. The reason for all the additional work of writing zero and erase is that flash memory has an additional state outside zero and one, called erased. If you write all zeros or all ones to the sector, it needs to be erased before you can write it again. So it is more efficient to erase when you want to just blank it out. So the firmware does not have to zero it out next time around.
After wiping out the contents, then some initial values (FAT table, etc) are written to define the file system (the official format). It is up to the camera manufacture to decide whether to zero out the card or to use the card's erase card command when wiping out the original content before use. All I can say is even I wouldn't know which camera uses what.
I know this is minor, actually tiny, but I just deleted about 1 gig off of a CF card by using the "erase all" function in the camera. It showed 64k on the card. I then formatted in the camera and it now shows 32k.
Like I said its tiny but at least with Canon cameras there is a difference.
Like I said its tiny but at least with Canon cameras there is a difference.
Originally Posted By: tom slick
I know this is minor, actually tiny, but I just deleted about 1 gig off of a CF card by using the "erase all" function in the camera. It showed 64k on the card. I then formatted in the camera and it now shows 32k.
Like I said its tiny but at least with Canon cameras there is a difference.
It is probably some residue hidden file that Canon kept on the card.
I know this is minor, actually tiny, but I just deleted about 1 gig off of a CF card by using the "erase all" function in the camera. It showed 64k on the card. I then formatted in the camera and it now shows 32k.
Like I said its tiny but at least with Canon cameras there is a difference.
It is probably some residue hidden file that Canon kept on the card.
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Thank you So much for all that inforamtion. So is my wifes honor reasonably safe after formating the card in the computer?? I also notcied there are more than one format options. For PC and Mac does it matter in case of a memory card for a camera?
Originally Posted By: Oilpants
Thank you So much for all that inforamtion. So is my wifes honor reasonably safe after formating the card in the computer?? I also notcied there are more than one format options. For PC and Mac does it matter in case of a memory card for a camera?
For a typical camera card that is designed right, it should not be any reliability or durability difference regardless of what types of format you use. Unless you buy a card that has a reputation of losing data, or slow to a haul after being used for a short period of time, you don't need to worry about it.
No difference between PC and Mac in format; it is a 15-20 year old standard that everyone should know how to do it right by now.
Thank you So much for all that inforamtion. So is my wifes honor reasonably safe after formating the card in the computer?? I also notcied there are more than one format options. For PC and Mac does it matter in case of a memory card for a camera?
For a typical camera card that is designed right, it should not be any reliability or durability difference regardless of what types of format you use. Unless you buy a card that has a reputation of losing data, or slow to a haul after being used for a short period of time, you don't need to worry about it.
No difference between PC and Mac in format; it is a 15-20 year old standard that everyone should know how to do it right by now.
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