Delete pictures or just Format...Which?

A digital camera CF memory card, Nikon D70s.
What is correct, after transferring the pictures
to a CD-R.
1)do you just delete the pictures on the card.
2)Or do you delete them, then format the card.
3)Or just format the card which will automatically
delete the pictures and format the card.

I have used #3 up to now, but recently was told
if you format the card often to delete pictures
you will damage the card.
I was told don't format just delete the pictures.

Is there a right way to do this?

Thanks in advance.
Denny B

 

I just delete the files and leave any folders the camera created. I also
don't share cards between devices. Each SD device or CF device has its own
set of cards that away I don't mess up the file numbering. Just my way of
doing. I am sure formatting is fine.

R

 

I do No.3
I suspect that the story of damaging the card by formatting in the
camera is an urban myth. I don't see how that is possible.
I've probably formatted my SD card 40-50 times with no problem.
Bob Williams

 

: Denny B wrote:
: > A digital camera CF memory card, Nikon D70s.
: > What is correct, after transferring the pictures
: > to a CD-R.
: > 1)do you just delete the pictures on the card.
: > 2)Or do you delete them, then format the card.
: > 3)Or just format the card which will automatically
: > delete the pictures and format the card.
: >
: > I have used #3 up to now, but recently was told
: > if you format the card often to delete pictures
: > you will damage the card.
: > I was told don't format just delete the pictures.
: >
: > Is there a right way to do this?
: >
: > Thanks in advance.
: > Denny B

: I do No.3
: I suspect that the story of damaging the card by formatting in the
: camera is an urban myth. I don't see how that is possible.
: I've probably formatted my SD card 40-50 times with no problem.
: Bob Williams

There is a finite number of times that a particular memory location can be
written to before it electronically wears out. But in most memory devices
I have seen stats on, this number is somewhere around 100,000 times or
more. Erasing an image removes the index from the file allocation table
(FAT) but does not overwrite the actual memory locations. A Format does.
So yes, formating instead of erasing will wear out the card faster, but
unless you are a very prolific photographer the difference between 50,000
and 100,000 uses is probably not a big problem.

Having said that, my experience has shown that my camera and equipment
seems to not have a problem with a card that just has had the images
erased, instead of a full format. So that is what I do. If I begin having
problems with capacity not coming back to full, THEN I do a format. But
that is me, and my equipment. Either way is ok.

Randy

==========
Randy Berbaum
Champaign, IL

 

A normal format does not. I have recovered data from a card that had
been formatted after repair damage cause be a battery failure during a
write. Incidentally, if you want to ensure data is never recovered from
a card you should incinerate it, overwriting is not adequate.

 

Doesn't happen with mine. It uses the folders I leave behind just fine. I
have never had more than one set of directories on any of my cards from any
of my Panasonic cameras.

R

 

Not sure there's a 'right way'; the only thing I would avoid is formatting
in a card reader. I always delete in the card reader after verifying the
copy went ok, then format in the camera. Never heard that deleting
in-camera will damage the card, nor have I had problems doing this.

Mark

 

Mark B. wrote:
[]

Why go through the extra step of deleting in the card reader if you are
going to reformat in the camera? It's more work and uses up more of the
card's write cycles.

David

 

Actually, it's the other way around! But, as you say, academic. I almost
always use format, in part because it takes about 2 or 3 seconds instead
of ten or so.

 

David is right. Formatting in camera is also faster than deleting all
via any means.

But what I want to know is why this tiresome topic has to come up every
other month and be so thoroughly rehashed?

 

That's true for magnetic media, where a small percentage of
previously written data can be recovered. Flash cards aren't
compromised by imprecise mechanical alignment, and any recovery of
previous data would be far less successful, would probably require
physically removing the flash memory from its case so that
sophisticated electronics could replace the card's controller, and
what little might be recovered would depend on the data pattern that
was used to overwrite the previously written data. If recovering
overwritten data was a simple as you may (or may not) be implying,
then by overwriting a 1GB card several times (with varying data
patterns), 2GB, 3GB or even many GB's of data could be recovered
from it, which is well beyond the capabilities of even a Poindexter.

 

If you always delete files in the card reader, by the time the
card has been worn out, it'll probably be obsolete, and your cameras
will probably be using cards with capacities in excess of 200 GB.
For my first camera I bought a 64MB card, and added a 96MB card
several months later. Used 'em for a good number of years and they
haven't worn out yet. Do you have any old cards of comparable size?
If so, how often do you use them?

I agree, though, that it's usually more practical to format cards
in the camera, but that's not the best approach for everyone. My
cards are occasionally shared between several cameras (different
brands) and some cameras wouldn't give any clues that the card
contains images saved by another camera, and formatting the card
would easily wipe out the other camera's images. The card may
contain other types of data, such as files copied to it from a
computer, or software provided by the card's manufacturer, all of
which would be lost when formatting the card. It might be
relatively safe to format your own cards, but if the cards belong to
someone else . . .

 

The newsgroup has a playlist of several dozen tiresome topics.
Increase the size of the playlist to several hundred topics and it
might then come up every year or two. We'd be no better off. But
in any case, the regulars and lurkers here are a constantly changing
group, and for some of the newbies this rehashing will present them
with fresh, useful information.

 

ASAAR wrote:
[]

Do people really share cards between devices that much? I tend to use one
set of cards in one camera, and have never felt the need for a "music"
player or whatever. Of course, a professional or keen amateur may well
have several camera bodies, and therefore need to be more careful, as you
say.

I tend to format only before the start of a major session (e.g. some days
away), and not between sessions, though. I'm not taking pictures every
day.

David

 

And ASAAR, while it's said that what you said about magnetic media is
technically accurate, you might have added that recovery of overwritten
data is no trivial task. It requires special skills and equipment. As
I've pointed out before, the best minds in the business didn't get very
far with the Nixon tapes. I know we are talking about a rather different
media, but the idea is similar, although in all fairness, it's likely
the erase head in a tape recorder presents more of a challenge. Of
course, since freeware that will overwrite to military security
standards is readily available, the more paranoid amongst can sleep
worry free (if they use it).
Having said all that, anyone discarding a computer hd should do at least
something about overwriting all tracks.
Dave Cohen

 

See <http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html>

 

I don't share cards very much, but enough to discover that some
cameras recognize some "alien" image folders and other don't. My
PDA uses SD cards but my cameras only use CF or xD, and my cell
phone doesn't use cards at all.

I did use the cards to transfer several GBs worth of data to a new
computer recently, and was surprised to note that while all of the
ports on the new computer were high speed (USB 2 HS & Firewire), the
computer's built-in multicard readers only transferred at the much
slower USB 2 FS/USB 1.1 data rate. Even file delete operations were
significantly slower than similar operations using a SCSI card
reader attached to my ancient Win95 computer, so I suppose I'll be
looking to get a card reader that's compatible with USB 2.2 HS.

 

Yes, very expensive equipment. And equipment that isn't readily
available. Trying to obtain some might even get one noticed by the
wrong people or organizations.

I haven't gone to that trouble yet, but that's because the only
thing I'd worry about would be personal data (Soc. Sec. & CC
numbers, etc.) getting into the hands of petty thieves) and they
wouldn't get very far because I usually disassemble the drives to
remove the powerful coil magnets. One very small one, about the
size of the pen/pencil erasers that can be bought for about a dollar
each has hanging from it several very large, heavy pots and pans. I
don't imagine that the magnets in drives currently used with
personal computers would be as strong, as these came from relatively
large Seagate full height 5" drives. Anyone having the ability to
recover data from the discarded platters is welcome to try, but I
highly doubt that my old ones would be of any interest to them.
I've saved a couple, as they make nice, shiny paperweights, or
OddJob style weapons for Fleming afficionados.

 

I suggest that you read that once more, this time trying to
understand the practical implications of the paper, which primarily
addressed magnetic media. Only a small bit of coverage was given to
memory, and that was for DRAM, not flash technology. Assuming one
has sophisticated equipment that examines each bit's signal level
(not just the ones and zeros that your computer would see), and/or
the ability to use manufacturer's undocumented test modes (where one
of the memory's I/O pins is used as the RAM's power supply - hah!)
one would still have to attempt to examine the data very soon after
it was rewritten. According to the paper, the DRAM's previously
stored data isn't held by the DRAM's cell so much as by the cell's
oxide layer, and to get the most accurate sensing of previously
written data, you'd want to read it within a "few microseconds" of
overwriting the data. Don't forget that you weren't talking about
the same media that this paper addresses, namely magnetic media and
DRAM, but about flash memory, which you claimed would require
incineration to prevent recovery even after its data was
overwritten. It also helps (as alluded to by Dave) to know not only
the difference between what's theoretically possible and what's
practical, but to make the difference clear as well, unless it's
your goal to create legions of fearful Chicken Littles.

I suspect that if you wanted to *really* protect your valuable
data, it would be better to incinerate yourself, because extracting
it from overwritten flash cards would present more of a problem than
simply sending you or those close to you to Gitmo, or using a gulag
rendition to extract the data. Do you have a fear of mean dogs?

 

My workhorse is a 512 MB Corsair 133X SD Card. (Bought on sale, naturally)
I have used it in 3 different cameras and I regularly download edited
image files and text files to it from my computer. In effect, I use it
as a camera memory and a thumb drive. I've never had any kind of problem
with it. It is a versatile little booger.
Typically, I'll shoot a bunch (30-40) of pictures in an outing and
download them to my computer. I usually leave the pics on the card in
case I want to show them to someone. I'll continue doing this until I
have used up about 460-480 MB. Then I archive the entire card on a CD.
Then I format the card in the camera and start anew.
There are countless variations on this theme, all equally valid, but
FWIW, this is my SOP.
Bob Williams