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everest63
10th of March 2009 (Tue), 12:30
Hello,

I have an EOS 20D.
I use a SanDisk Extreme USB 2.0 card reader to copy images off the SanDisk Extreme III 4GB CF card. I then put the CF card back into the 20D and delete all the images using the camera. This as you know deletes the images but leaves the folders intact (empty). Is it best to delete images or use the format option? Will formatting the CF card delete the current folders and then create a new folder?
Delete or format?
:)

Oh, almost forgot, I have the camera file numbering set to "Continuous". File numbering option "Auto Reset" a better option?

gary88
10th of March 2009 (Tue), 12:33
I always format my card after I transfer my images to my computer. Completely wiping the card makes it much less likely that you'll ever get a corrupted file.

Brett
10th of March 2009 (Tue), 14:14
I've been wondering this myself. I use a card reader for both types of cards I have, and I usually just open the folder and select the images and drag them to a folder, then delete them off the card on the PC.

I've heard people say "format on the PC", "format in the camera", "never format", "always format", etc.

I still don't know what's "right".

gjl711
10th of March 2009 (Tue), 14:21
I don't think that there is a right or wrong. All techniques seem to work fine for those using them. I can state what I use and you can draw your own conclusions from that. I always move the pics over from the CF card, back them up, then re-format the card using a full format in PC. It has worked flawlessly for me.

silvrr
10th of March 2009 (Tue), 14:24
Intresting. I have noticed my new 40d doesnt have a delete all option like my 400D did. So I have been deleting large numbers of files in camera rather than one by one using the erase button (usually when I am experimenting or just goofing off).

I was wondering if this would have any undesired effects if its done alot. Ill have to check back on this thread.

gdl357
10th of March 2009 (Tue), 14:26
I just got my first SLR, 50D 3 weeks ago.

I don't like the idea of opening the camera door and pulling and inserting my $200 cards every 15 minutes when I do my test shots. I rather just plug the mini-USB cable in the camera instead. No chance of bending my pins inside my camera or wearing/losening the ones out in my card.

After the upload to PC, I format the card in camera options section.

I got use to that.

Orchid Crazy
10th of March 2009 (Tue), 14:34
I rarely take my CF card out; mainly to exchange it with an empty card if I fill one up. I use a USB cord and leave the CF card in the camera. After I am done uploading pics, I format the card in camera.

TITROY
10th of March 2009 (Tue), 14:36
Delete means the characteristics of the file are deleted from the MAP.
It works exactly in the same way on your PC. You can rescue the files with the appropriate program.

Format erases all the sectors of the MAP (it writes all the sectors) : you cannot retrieve the files.
From time to time, it is good to format the CF : it also check all the sectors.

Take also care not to delete a very big number of files followed by new shots between two 'delete all' or 'format' : when you delete a file, the space is available again only if the size of a new one is smaller or same: as a consequence, it could take time to write on the CF or the file could be corrupted.

Balliolman
10th of March 2009 (Tue), 14:44
Be consistent with you deleting/formatting practise and you will not likely have problems with cards.

Mark_Cohran
10th of March 2009 (Tue), 14:45
I'm of the "format" school of thought.

Thalagyrt
10th of March 2009 (Tue), 14:46
Delete means the characteristics of the file are deleted from the MAP.
It works exactly in the same way on your PC. You can rescue the files with the appropriate program.

Format erases all the sectors of the MAP (it writes all the sectors) : you cannot retrieve the files.
From time to time, it is good to format the CF : it also check all the sectors.

Take also care not to delete a very big number of files followed by new shots between two 'delete all' or 'format' : when you delete a file, the space is available again only if the size of a new one is smaller or same: as a consequence, it could take time to write on the CF or the file could be corrupted.

Most formats are just a quick format, which is done by wiping out the superblocks and creating a new filesystem. If it happens in a matter of seconds, no, it hasn't done any error checking, or any form of actual formatting aside from creating a new filesystem in place of the old one. A full format, which no camera does, and most computers will only do if you specifically ask them to, will write out a 0 to every block in the newly created filesystem, not the entire card, and yes, you'll get any blocks that might be going bad marked. But that's completely unnecessary as the cards do that with regular usage anyway, as I've pointed out below.

Honestly, almost everything you said is incorrect. Error checking on CF cards is done at write time. If there's any issue writing, that block is marked bad and the data is written elsewhere. Unlike a magnetic or optical disc, fragmentation is a non-issue as flash memory does not have any form of seek time, so your last point about possible longer write times is entirely moot.

Lastly, unlike regular write blocks, the superblocks on any storage device remain in the same locations no matter what. Repeated formatting will wear out the locations of the superblocks much more quickly than if you never format the card and just erase images, as those superblocks will not be touched aside from reads to determine the filesystem type. If that location dies, the entire card might as well be useless. Write distribution will occur for the filesystem's FAT entries, inodes, etc. depending on filesystem, but not for the superblocks.

For what it's worth, I am a computer engineer; you can trust me on this.

Side note: I'm baffled that people still use FAT for anything.

eosphotomanoftennessee
10th of March 2009 (Tue), 14:49
Canon recommends formatting in the camera, that's what I usually do. BTW you can "recover" images from a formatted card both in-camera format as well as PC. I have recovered files many many times for people who have through error formatted the wrong card and then started taking photos only to get done with session and find they had formatted wrong card. Lexar and San Disk both sell or give away the software. It is also available from other companies, I have used 3 different programs over the years, they all work.

Mark_Cohran
10th of March 2009 (Tue), 14:50
Just a quick question - How do you "wear out" locations on a flash memory device? I can understand it for magnetic media, but I'm not sure I quite understand how that would work for solid state.

Mark001
10th of March 2009 (Tue), 14:57
Lastly, unlike regular write blocks, the superblocks on any storage device remain in the same locations no matter what. Repeated formatting will wear out the locations of the superblocks much more quickly than if you never format the card and just erase images, as those superblocks will not be touched aside from reads to determine the filesystem type.

Since this is flash, you are going through a controller that translates writes from a logical sector to a physical sector. While a superblock may always be in the same logical sector, repeated writes to this sector will cause it to be rewritten to a new physical sector in the flash. Better controllers will even move static data to evenly wear the flash parts to extend their life.

CAL Imagery
10th of March 2009 (Tue), 14:58
Delete means the characteristics of the file are deleted from the MAP.
It works exactly in the same way on your PC. You can rescue the files with the appropriate program.

Format erases all the sectors of the MAP (it writes all the sectors) : you cannot retrieve the files.
From time to time, it is good to format the CF : it also check all the sectors.

Take also care not to delete a very big number of files followed by new shots between two 'delete all' or 'format' : when you delete a file, the space is available again only if the size of a new one is smaller or same: as a consequence, it could take time to write on the CF or the file could be corrupted.
Actually, you can recover formatted CF cards. I know from personal experience.:cool:

Thalagyrt
10th of March 2009 (Tue), 14:58
Just a quick question - How do you "wear out" locations on a flash memory device? I can understand it for magnetic media, but I'm not sure I quite understand how that would work for solid state.

Simple version: NAND RAM works very similar to normal RAM, aside from needing a constant voltage to refresh its state. Contrary to what seems logical, each cell (bit) has a certain threshold for what is 0 and what is 1. Much like on magnetic media, a tiny remnant of the last write remains. Eventually you hit a threshold where the voltage levels become indistinguishable to the controller - is it a 1 or a 0? - and at that point that block cannot be read properly. As you write to NAND RAM, the voltage levels on each block are checked. If they're starting to get into the dangerous territory, that block is marked bad (long before it actually would be bad) and the block is written elsewhere.

CAL Imagery
10th of March 2009 (Tue), 14:59
Intresting. I have noticed my new 40d doesnt have a delete all option like my 400D did. So I have been deleting large numbers of files in camera rather than one by one using the erase button (usually when I am experimenting or just goofing off).

I was wondering if this would have any undesired effects if its done alot. Ill have to check back on this thread.
Look under the left blue play tab under the menu for erase images.

Thalagyrt
10th of March 2009 (Tue), 15:02
Since this is flash, you are going through a controller that translates writes from a logical sector to a physical sector. While a superblock may always be in the same logical sector, repeated writes to this sector will cause it to be rewritten to a new physical sector in the flash. Better controllers will even move static data to evenly wear the flash parts to extend their life.

I'm aware of write mapping, however cheaper/older cards don't do this nearly as well. Either way, there still is a set of blocks that are used by the remapper to keep track of where the filesystem's start is, and that is the superblock that I was talking about. The superblock isn't the filesystem, it's the first 512 bytes of any media, and the controller needs that to initialize so it can find the media.

It's been a while since I've worked with I/O controllers, so superblock might be the wrong word for this, however my point is that the first 512 byte block must remain in a place where the controller always knows where it is, and with remapping, well it still needs to remain in the same place so the controller knows where to start when it's powered on.

gdl357
10th of March 2009 (Tue), 15:03
Lastly, unlike regular write blocks, the superblocks on any storage device remain in the same locations no matter what. Repeated formatting will wear out the locations of the superblocks much more quickly than if you never format the card and just erase images, as those superblocks will not be touched aside from reads to determine the filesystem type. If that location dies, the entire card might as well be useless. Write distribution will occur for the filesystem's FAT entries, inodes, etc. depending on filesystem, but not for the superblocks.



This I don't believe. Sorry. :cry: This is not a card that has a mini mechanical HDD in it that writes and erases with magnetism. We are talking about MEMORY here, right?

I think I will end up getting grey before I wear out a CF card by formating.

Most memory type chips have 150 000 hours of use...that's about 20 years. Even the boot sectors on HDD's don't wear out that fast. I have hdd's working great loading windows every day after 12 years of use. WD80GB to give you an idea.

They would not give a Limited lifetime warranty on my Lexar Pro cards if this was the case. It would be more like a 2 year warranty. All the power to formatting!

Thalagyrt
10th of March 2009 (Tue), 15:06
This II don't believing. Sorry. :cry: This is not a card that has a mini mechanical HDD in it that writes an erases with magnetism we are talking about here, right?

I think I will end up getting grey before I wear out a CF crd by formating.

Most memory type chips have 150 000 hours of use...that's about 20 years. Even the boot sectors HDD's don't wear out fast. I have hdd's working great loading windows even after 12 years. WD80GB to give you an idea.

They would not give a Limited lifetime warranty on my Lexar Pro cards if this was the case. It would be more like a 2 year warranty. All the power to formatting!

Either way the cards will last a very long time. NAND memory isn't rated in hours of use, it's rated in write cycles. To be completely honest, you could do about 100k formats before you'd notice problems. By that time you'll probably have replaced the card anyway. And regarding hard drives, I have a 5.25" drive from back in the late 80s that still works. :)

fiorano94
10th of March 2009 (Tue), 15:10
Whenever I clear my card I format.

Mark_Cohran
10th of March 2009 (Tue), 15:11
Either way the cards will last a very long time. NAND memory isn't rated in hours of use, it's rated in write cycles. To be completely honest, you could do about 100k formats before you'd notice problems. By that time you'll probably have replaced the card anyway. And regarding hard drives, I have a 5.25" drive from back in the late 80s that still works. :)

So, from a user's practical standpoint, formating wouldn't be anymore destructive than erasing the files.

Thalagyrt
10th of March 2009 (Tue), 15:13
So, from a user's practical standpoint, formating wouldn't be anymore destructive than erasing the files.

Yea, after some further thought I realized that, and feel like a total idiot for getting into a debate about it. Haha. :o

I'm so used to seeing embedded devices where logfile writes and such can kill flash memory very quickly, that it made me bring that school of thought over to photography.

mrkgoo
10th of March 2009 (Tue), 15:22
Intresting. I have noticed my new 40d doesnt have a delete all option like my 400D did. So I have been deleting large numbers of files in camera rather than one by one using the erase button (usually when I am experimenting or just goofing off).

I was wondering if this would have any undesired effects if its done alot. Ill have to check back on this thread.

I believe the delete all is now a function in the menu (with the lock and unlock images).

bohdank
10th of March 2009 (Tue), 15:32
I transfer my cards using an external reader. Since I have been using digital cameras, 2000, I just delete from the PC. I may, once in a blue moon format, in camera, but that's usually because I forgot to delete the images from the card before putting it into the camera. An extremely rare event.

toxic
10th of March 2009 (Tue), 15:37
Actually, you can recover formatted CF cards. I know from personal experience.:cool:

data can be recovered from reformatted disks until the data has been overwritten. In other words, a full format, where everything is overwritten with a zero, makes it extremely difficult to recover data. Places like the CIA will overwrite all of their data multiple times.

Thalagyrt
10th of March 2009 (Tue), 15:39
data can be recovered from reformatted disks until the data has been overwritten. In other words, a full format, where everything is overwritten with a zero, makes it extremely difficult to recover data. Places like the CIA will overwrite all of their data multiple times.

It's amazing what the expensive toys can do when it comes to data recovery! :D

kosin
10th of March 2009 (Tue), 15:44
I always format my cards in camera (never with PC/Mac) unless I forget to do so and start shooting than I lock new images and delete the rest. Anyway, I always had a feeling that formating is better and faster than deleting...

Supa Lao
10th of March 2009 (Tue), 19:57
I've always format my card in the camera when I'm done uploading to my pc.

yogestee
10th of March 2009 (Tue), 20:43
I always use a card reader or PCMCIA/CF adapter for my lappy.. I transfer the images I need via EOS Viewer Utility then delete all images when I've finished..

I'll in camera format every few weeks.. As of now I've not had any corrupt images (touch wood)..

TMCCaptured
10th of March 2009 (Tue), 20:58
Side note: I'm baffled that people still use FAT for anything.[/quote]

My Granny uses it for Christmas Ham and boy the one time I over eat is when I go to my Granny's. Apple Sauce, Roast Spuds-carrots-Parsnips-Kumra oh my mouth is watering. But dont let my Granny Baffle you she is a sweet old thing I love to bits

I have to agree with you on this one as well but being a noob I can see a flaming coming on if I open my mouth

CAL Imagery
10th of March 2009 (Tue), 21:11
data can be recovered from reformatted disks until the data has been overwritten. In other words, a full format, where everything is overwritten with a zero, makes it extremely difficult to recover data. Places like the CIA will overwrite all of their data multiple times.
I understand that, except I though if I reformat my computer HDD, it would wipe everything out? I was laughing in December when I recovered pictures that I found a few from August.

WaltA
11th of March 2009 (Wed), 10:12
I think the format question is a "Ford/Chevy" one - you'll get many opions both sides.
But in most photography books I've read the auther says they format in the camera.

I can say I've done both but do it in the camera regularly. Thats probably because of my old computer days with small slow hard drives that slowed down when the disk got fragmented and so you had to de-frag (or format it) regularly. I know that probably has no bearing whatsoever on a CF card - but old habits die hard.