«

Hi there,

Half a year ago I bought a no-name SD card via eBay from Singapore (2
GB, 133x/80x read/write speed, manufacturer "Magu").

Couple of months ago, my camera (Panasonic LX1) gave a writing error,
and I could not snap pictures anymore. I turned the camera off, then
on. After this procedure, the camera wrote pictures, and I never had
problems with the card since.

Few days ago, I ran the SD card through "Disk Checker" (on my Windows
PC) which can be downloaded from the Internet. The Disk Checker
reported that about a quarter of sectors (clusters) was "bad". I
formatted the card using the camera, then ran the SD card through Disk
Checker again. There were the same bad sectors present. That was
strange. I had no problems with writing/reading files from the card.

So I snapped the pictures and wrote them into the SD card until it was
full. There were no writing problems. I presume that if some sectors
were bad, the camera would not be able to write to them, and gave me
the error. Or, when I am using the camera to write the files to the SD
card, the controller on the SD card finds that the sector is "bad", and
does not write to there ?

The return policy is not favourable. I think I prefer to mark the bad
clusters as bad using the software, and keep using the card. I am
curious if this "marking" disappears when the card is formatted.

I would appreciate hearing from you.

...

By using some disk utility software you should be able to map out the bad
sectors. They may even already be mapped out but your disk checker software
is simply doing a low level verification of the sectors and reporting the
bad ones even though they are mapped out.

It shouldn't be a problem, but if it bugs you, 2GB SD cards are very
inexpensive now - under $30 for branded standard speed one (your LX1 isn't
going to benefit greatly from a very fast card unless you want to shoot very
long continuous shooting sequences). A high pseed SanDisk Ultra III is now
under $50.

Ian

Digital Photography Now
http://dpnow.com

*** Extra 40MB of storage space on DPNow's free photo gallery until the end
of November, don't miss it while it's there! http://galleries.dpnow.com

"minnesøtti" <> wrote in message
news: oups.com...
> Hi there,
>
> Half a year ago I bought a no-name SD card via eBay from Singapore (2
> GB, 133x/80x read/write speed, manufacturer "Magu").
>
> Couple of months ago, my camera (Panasonic LX1) gave a writing error,
> and I could not snap pictures anymore. I turned the camera off, then
> on. After this procedure, the camera wrote pictures, and I never had
> problems with the card since.
>
> Few days ago, I ran the SD card through "Disk Checker" (on my Windows
> PC) which can be downloaded from the Internet. The Disk Checker
> reported that about a quarter of sectors (clusters) was "bad". I
> formatted the card using the camera, then ran the SD card through Disk
> Checker again. There were the same bad sectors present. That was
> strange. I had no problems with writing/reading files from the card.
>
> So I snapped the pictures and wrote them into the SD card until it was
> full. There were no writing problems. I presume that if some sectors
> were bad, the camera would not be able to write to them, and gave me
> the error. Or, when I am using the camera to write the files to the SD
> card, the controller on the SD card finds that the sector is "bad", and
> does not write to there ?
>
> The return policy is not favourable. I think I prefer to mark the bad
> clusters as bad using the software, and keep using the card. I am
> curious if this "marking" disappears when the card is formatted.
>
> I would appreciate hearing from you.
>
> ..
>

"minnesøtti" <> wrote in message
news: oups.com...
> Hi there,
>
> Half a year ago I bought a no-name SD card via eBay from Singapore (2
> GB, 133x/80x read/write speed, manufacturer "Magu").
>
> Couple of months ago, my camera (Panasonic LX1) gave a writing error,
> and I could not snap pictures anymore. I turned the camera off, then
> on. After this procedure, the camera wrote pictures, and I never had
> problems with the card since.
>
> Few days ago, I ran the SD card through "Disk Checker" (on my Windows
> PC) which can be downloaded from the Internet. The Disk Checker
> reported that about a quarter of sectors (clusters) was "bad". I
> formatted the card using the camera, then ran the SD card through Disk
> Checker again. There were the same bad sectors present. That was
> strange. I had no problems with writing/reading files from the card.
>
> So I snapped the pictures and wrote them into the SD card until it was
> full. There were no writing problems. I presume that if some sectors
> were bad, the camera would not be able to write to them, and gave me
> the error. Or, when I am using the camera to write the files to the SD
> card, the controller on the SD card finds that the sector is "bad", and
> does not write to there ?
>
> The return policy is not favourable. I think I prefer to mark the bad
> clusters as bad using the software, and keep using the card. I am
> curious if this "marking" disappears when the card is formatted.
>
> I would appreciate hearing from you.

It seems to me that the only errors you are encountering are those found by
the PC's disk checker utility, specifically when it writes and reads
individual sectors. If this is the case, and the camera does not encounter
errors when writing, and the images are read OK on the PC, this is a
non-problem.

Possibly there is a timing issue with your PC's card reader. As DPN says,
these large cards are very inexpensive now - get another one, and if it
shows similar errors, I bet the problem is with the card reader, and not the
card.
--

Mike Russell
www.curvemeister.com/forum/

"minnesøtti" <> wrote in message
news: oups.com...
> Hi there,
>
> Half a year ago I bought a no-name SD card via eBay from Singapore (2
> GB, 133x/80x read/write speed, manufacturer "Magu").
>
> Couple of months ago, my camera (Panasonic LX1) gave a writing error,
> and I could not snap pictures anymore. I turned the camera off, then
> on. After this procedure, the camera wrote pictures, and I never had
> problems with the card since.
>
> Few days ago, I ran the SD card through "Disk Checker" (on my Windows
> PC) which can be downloaded from the Internet. The Disk Checker
> reported that about a quarter of sectors (clusters) was "bad". I
> formatted the card using the camera, then ran the SD card through Disk
> Checker again. There were the same bad sectors present. That was
> strange. I had no problems with writing/reading files from the card.
>
> So I snapped the pictures and wrote them into the SD card until it was
> full. There were no writing problems. I presume that if some sectors
> were bad, the camera would not be able to write to them, and gave me
> the error. Or, when I am using the camera to write the files to the SD
> card, the controller on the SD card finds that the sector is "bad",
> and
> does not write to there ?
>

You say there were "no writing problems", however, did you
look at the pictures and see if any of them were corrupted??
It may be it writes to the card but does not verify the write.
It may also be the formatting has already accounted for those
sectors -- when you select all the pictures on the card when
it is "full" does it total close to the 2 gig of the card or some
significantly lesser amount ??? (indicating the bad "sectors" have
already been accounted for)

mikey

Mike Fields wrote:
>
> "minnesøtti" <> wrote in message
> news: oups.com...
>> Hi there,
>>
>> Half a year ago I bought a no-name SD card via eBay from Singapore (2
>> GB, 133x/80x read/write speed, manufacturer "Magu").
>>
>> Couple of months ago, my camera (Panasonic LX1) gave a writing error,
>> and I could not snap pictures anymore. I turned the camera off, then
>> on. After this procedure, the camera wrote pictures, and I never had
>> problems with the card since.
>>
>> Few days ago, I ran the SD card through "Disk Checker" (on my Windows
>> PC) which can be downloaded from the Internet. The Disk Checker
>> reported that about a quarter of sectors (clusters) was "bad". I
>> formatted the card using the camera, then ran the SD card through Disk
>> Checker again. There were the same bad sectors present. That was
>> strange. I had no problems with writing/reading files from the card.
>>
>> So I snapped the pictures and wrote them into the SD card until it was
>> full. There were no writing problems. I presume that if some sectors
>> were bad, the camera would not be able to write to them, and gave me
>> the error. Or, when I am using the camera to write the files to the SD
>> card, the controller on the SD card finds that the sector is "bad", and
>> does not write to there ?
>>
>
> You say there were "no writing problems", however, did you
> look at the pictures and see if any of them were corrupted??
> It may be it writes to the card but does not verify the write.
> It may also be the formatting has already accounted for those
> sectors -- when you select all the pictures on the card when
> it is "full" does it total close to the 2 gig of the card or some
> significantly lesser amount ??? (indicating the bad "sectors" have
> already been accounted for)
>
> mikey
>


PC disk utilities often look at the FCB table to learn the drive
translations, including bad track map. Initially, the bad track map is
simply included in the sector report, and recovery of the bad tracks can
be attempted, but ill advised.

I had a 2g Lexar CF card with a bad track map, and I attempted to
recover the bad tracks, some of which were successful. My KM7D now sees
a 3.1g CF card and adjusts the predicted image counts accordingly. So,
I've presumed some of the "bad tracks" were marked bad to render it's
retail size and price.

Smallish cards today may have been intended to be larger cards, but
failed sectors discovered in lo-level formatting by the manufacturer
rendered the retail label and price. The idea of a manufacturing line
for each size card seems crazy, likely the smaller sizes are the result
of tests with varying amounts of bad sectors.

Or, I could be totally confused and my experience is simply a fluke in
the overall scheme of things - which is likely to be normal around here.

--
jer
email reply - I am not a 'ten'

"Jer" <> wrote in message
news:...
Mike Fields wrote:
>
> "minnesøtti" <> wrote in message
> news: oups.com...
>> Hi there,
>>
>> Half a year ago I bought a no-name SD card via eBay from Singapore (2
>> GB, 133x/80x read/write speed, manufacturer "Magu").
>>
>> Couple of months ago, my camera (Panasonic LX1) gave a writing error,
>> and I could not snap pictures anymore. I turned the camera off, then
>> on. After this procedure, the camera wrote pictures, and I never had
>> problems with the card since.
>>
>> Few days ago, I ran the SD card through "Disk Checker" (on my Windows
>> PC) which can be downloaded from the Internet. The Disk Checker
>> reported that about a quarter of sectors (clusters) was "bad". I
>> formatted the card using the camera, then ran the SD card through
>> Disk
>> Checker again. There were the same bad sectors present. That was
>> strange. I had no problems with writing/reading files from the card.
>>
>> So I snapped the pictures and wrote them into the SD card until it
>> was
>> full. There were no writing problems. I presume that if some sectors
>> were bad, the camera would not be able to write to them, and gave me
>> the error. Or, when I am using the camera to write the files to the
>> SD
>> card, the controller on the SD card finds that the sector is "bad",
>> and
>> does not write to there ?
>>
>
> You say there were "no writing problems", however, did you
> look at the pictures and see if any of them were corrupted??
> It may be it writes to the card but does not verify the write.
> It may also be the formatting has already accounted for those
> sectors -- when you select all the pictures on the card when
> it is "full" does it total close to the 2 gig of the card or some
> significantly lesser amount ??? (indicating the bad "sectors" have
> already been accounted for)
>
> mikey
>


PC disk utilities often look at the FCB table to learn the drive
translations, including bad track map. Initially, the bad track map is
simply included in the sector report, and recovery of the bad tracks can
be attempted, but ill advised.

I had a 2g Lexar CF card with a bad track map, and I attempted to
recover the bad tracks, some of which were successful. My KM7D now sees
a 3.1g CF card and adjusts the predicted image counts accordingly. So,
I've presumed some of the "bad tracks" were marked bad to render it's
retail size and price.

Smallish cards today may have been intended to be larger cards, but
failed sectors discovered in lo-level formatting by the manufacturer
rendered the retail label and price. The idea of a manufacturing line
for each size card seems crazy, likely the smaller sizes are the result
of tests with varying amounts of bad sectors.

Hey, that takes me back a number of years. Back in the days of
CP/M, I had a 32k memory board that used special versions of
the 4116 dynamic memory chips (the 4116 was 16k by 1). These
chips were 4115-4x where "x" was either a 1 or 2 if I remember
correctly -- they were 4116 chips with either the top half or bottom
half bad. You jumpered your board to use the appropriate half of
the chip. Come to think of it, I probably still have that board with
32k bytes of memory on it downstairs in a box. 32k (yes k) was
HUGE back then !!!

mikey