Sandisk CF card issue


Turbonetics

Senior Member
Feb 19, 2009
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Hi guys, I need some help here over my Sandisk CF Card 16gb.
I could usually shoot 500-600 plus of photos on an empty card but notice that the number has dropped significantly to 200 plus.
I tried to delete photos and Format the card but it still shows the same 200 plus shots.
However,from my computer it shows the memory available is about 7Gb.
I can't find those photo files from my computer or view it from my camera.
How can I retrieve back those memory space?

Thank you.
 

Hi guys, I need some help here over my Sandisk CF Card 16gb.
I could usually shoot 500-600 plus of photos on an empty card but notice that the number has dropped significantly to 200 plus.
I tried to delete photos and Format the card but it still shows the same 200 plus shots.
However,from my computer it shows the memory available is about 7Gb.
I can't find those photo files from my computer or view it from my camera.
How can I retrieve back those memory space?

Thank you.

Bro, card is about to die.
 

Hi guys, I need some help here over my Sandisk CF Card 16gb.
I could usually shoot 500-600 plus of photos on an empty card but notice that the number has dropped significantly to 200 plus.
I tried to delete photos and Format the card but it still shows the same 200 plus shots.
However,from my computer it shows the memory available is about 7Gb.
I can't find those photo files from my computer or view it from my camera.
How can I retrieve back those memory space?

Thank you.

FYI.

Flash Memory Chips in your CF card does not last forever. Only so many times you can read/write to it before it fails. I think is is about 100,000 times or there about. There usually is a mean of distributing how data is written to the card.

A 16 gig card for example, has a programmed method set into a card that ensure each byte of that 16 gigabyte flash memory be equally written to thus, reach close to the 100,000th read/write of that 16gig thereby giving your card a life span of a given length of time.

You find it will stop allowing you to write more data to it as more and more of bytes starts to fail. That is where you find less and less space available when you check available space. I have used CF cards since 2004, the moment I see signs of faulty read or write direct from the CF, weird failure start to happen with the camera or available space indicates less then the original capacity (16gig .eg) of the card even when formatted, that's when i throw the card or be very weary of using it further.

People who shoots a lot like Pros, ends up buying new card replacement frequently. You can't fight this inherent wear and tear properties of CF. I heard SD has a better longevity but it too will suffer that same fate. This is the same for SSD hard drives in computer over normal metal disc spinning hard drives. Spin disc tech was in CF size but it is too damn slow. Thus flash memory was used given their ability to read/write very fast.

http://havecamerawilltravel.com/photographer/memory-cards-wear-out

Note: MLC type flash memory are 10,000 to 50,000 read/write and SLC type flash memory are 100,000 read/write. Maybe you want to try and find out what type your card is using.
 

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Bro, card is about to die.

FYI.

Flash Memory Chips in your CF card does not last forever. Only so many times you can read/write to it before it fails. I think is is about 100,000 times or there about. There usually is a mean of distributing how data is written to the card.

A 16 gig card for example, has a programmed method set into a card that ensure each byte of that 16 gigabyte flash memory be equally written to thus, reach close to the 100,000th read/write of that 16gig thereby giving your card a life span of a given length of time.

You find it will stop allowing you to write more data to it as more and more of bytes starts to fail. That is where you find less and less space available when you check available space. I have used CF cards since 2004, the moment I see signs of faulty read or write direct from the CF, weird failure start to happen with the camera or available space indicates less then the original capacity (16gig .eg) of the card even when formatted, that's when i throw the card or be very weary of using it further.

People who shoots a lot like Pros, ends up buying new card replacement frequently. You can't fight this inherent wear and tear properties of CF. I heard SD has a better longevity but it too will suffer that same fate. This is the same for SSD hard drives in computer over normal metal disc spinning hard drives. Spin disc tech was in CF size but it is too damn slow. Thus flash memory was used given their ability to read/write very fast.

http://havecamerawilltravel.com/photographer/memory-cards-wear-out

Note: SLC type flash memory are 10,000 to 50,000 read/write and MLC type flash memory are 100,000 read/write. Maybe you want to try and find out what type your card is using.

Thank you. I didn't know memory cards will deteriorate as I thought should be lifetime warranty?
I just realised my other Sandisk card with same specs has the same issue but it allows only 100 plus photos.
I remember just few days ago they were still ok,does it happen in such a drastic drop or gradually drop?
These cards are not that old probably 1 year plus and 2 year plus old.
 

It could also be a simple fact of file system corruption. The typical 'format card' function only wipes the FAT (the file directory) but does not clear the data (which gives the good chances of recovering deleted files). FAT file systems are prone to different problems (fragmentation and other 'goodies', well known since Win95...). It is always the best the create a fresh and clean file system.
Use your computer and card reader to format the card. Remove the tick 'quick format'. This will create a fresh file system. If during the process there is any error popping up it indicates a problem with the memory cells or even worse. Usually, it's not worth continuing here. What works well on hard disks (mapping of bad sectors) does not work well here because there is another logic (memory controller) between the actual 'sectors' and the computer. Both interfere, creating more rubbish.
 

It could also be a simple fact of file system corruption. The typical 'format card' function only wipes the FAT (the file directory) but does not clear the data (which gives the good chances of recovering deleted files). FAT file systems are prone to different problems (fragmentation and other 'goodies', well known since Win95...). It is always the best the create a fresh and clean file system.
Use your computer and card reader to format the card. Remove the tick 'quick format'. This will create a fresh file system. If during the process there is any error popping up it indicates a problem with the memory cells or even worse. Usually, it's not worth continuing here. What works well on hard disks (mapping of bad sectors) does not work well here because there is another logic (memory controller) between the actual 'sectors' and the computer. Both interfere, creating more rubbish.

Thanks and will give it a try tonight using computer to Format it.
Hopefully it works.
 

Thank you. I didn't know memory cards will deteriorate as I thought should be lifetime warranty?
I just realised my other Sandisk card with same specs has the same issue but it allows only 100 plus photos.
I remember just few days ago they were still ok,does it happen in such a drastic drop or gradually drop?
These cards are not that old probably 1 year plus and 2 year plus old.

If you shoot a lot with the card, 2 years or there about can be old. I rad some card have been used for 5 years before dying. Once it starts with minor read/write problem, it gets quite bad really fast. It means almost all the "slots" that makes up each BYTE has been written to about 100,000 times and the algorithm that is use to read/write it as evenly as possible (wear leveling) has reach almost the same amount of read/write limit per byte.

It's like a room with 100 chairs, each has been sat on 100,000 times heheh... and imagine when it reach that quota, the chair break down all four legs. It has reach the point where there is no where to sit hehe.. hope you get my analogy now.

Anyone tell you there is a lifetime warranty on flash module card is lying to you big time heheh.

The reason some card can last longer then others depends on the size of your card. If you have a 8gig card and a 32 gig card and you shoot say 8 gig of photos on each ( that means your 32gig will still have 24gig left over) .. say you keep doing the same ratio all the time, soon you will find that your 8 gig will die first or start having problems way before your 32 gig will.

That is why you should mark your cards to know which one you bought earlier .. that way you have a means to know how long before they start to die out. Hard to say how long really. A person who is not crazy to shoot all the time, his card most likely will last a long time. But if you recall the card's age you bought them and you shoot consistently all these time, I think you already can see how often you need to prepare to buy new cards in case.. if you are a pro shooting weddings... wah scary if your cards fail. That is why I guess Pros will try to have two cards in the card saving photos twice at the same time. In case there is a failure.

Well, anyone who did not know that.... NOW YOU KNOW hehehhe.. becareful dude.

Note again, find out if your card is using the SLC or MLC. SLC will only take about 100,000 read/write while MLC is about 10,000 read/write ( sorry think I got it wrong earlier)

Like Octarine said, it could be file corruption caused by format. Always try to format from your camera then use your PC's. I learn that the hard way last time. I took out my card from the camera and stick it into a USB card reader. After the download, I thought to save time I format the card while it was in the card reader. the format worked fine but what i did not know was when i stick it back into my camera it did not work and worst the camera did not tell me something was wrong until I try to chim back to earlier photos and it showed no photos.

That was not a DSLR but a point and shot. Learn that the hard way. Always format it when it is back in your camera TO BE SURE. That is what I always do now even though I know you can format from the computer. But scare one time heheh....no more.

Something interesting to read about CF Memory flash failures: http://www.zachandjody.com/blog/why-your-cf-card-might-fail-at-your-next-shoot/19518/
 

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If you use them a lot 2 years or there about can be old. One it starts it gets quite bad really fast. It means almost all the "slots" that makes up each BYTE has been written about that 100,000 times and the algorithm that is use to read/write it as evenly as possible has reach almost the same amount of read/write limit per byte.

It's like a room with 100 chairs, each has been sat on 100,000 times heheh... and imagine when it reach that quota, the chair break down all four legs. It has reach the point where there is no where to sit hehe.. hope you get my analogy now.

Anyone tell you there is a lifetime warranty on flash module card is lying to you big time heheh.

The reason some card can last longer then others depends on the size of your card. If you have a 8gig card and a 32 gig card and you shoot say 8 gig of photos on each ( that means your 32gig will still have 24gig left over) .. say you keep doing the same ratio all the time, soon you will find that your 8 gig will die first or start having problems way before your 32 gig will.

That is why you should mark your cards to know which one you bought earlier .. that way you have a means to know how long before they start to die out. Hard to say how long really. A person who is not crazy to shoot all the time, his card most likely will last a long time. But if you recall the card's age you bought them and you shoot consistently all these time, I think you already can see how often you need to prepare to buy new cards in case.. if you are a pro shooting weddings... wah scary if your cards fail. That is why I guess Pros will try to have two cards in the card saving photos twice at the same time. In case there is a failure.

Well, anyone who did not know that.... NOW YOU KNOW hehehhe.. becareful dude.

I agree old or new is subjective.
but both combined I would rate at most 100,000 clicks.
and also both failing at the same time doesn't sound right isn't it?
somehow I feel there are "undeleted" photos still stored "inside".
 

I agree old or new is subjective.
but both combined I would rate at most 100,000 clicks.
and also both failing at the same time doesn't sound right isn't it?
somehow I feel there are "undeleted" photos still stored "inside".

That is not 100,000 clicks of your shutter button but 100,000 off/on action of each BYTE that makes up entire size of the card. For example 32gig. Imagine you shoot one raw shot. That is say 20mb. That is 20,000,000 byte in total that got written?? I think. heh I am lousy at math heh.. but yes.. just imagine that. Now imagine you shoot up the whole card with raw. Which can still seem like not a lot toyou. heheh. But calculate in BYTE size... that is a lot. There was a way to calculate this but I can't recall now heh.. I did see that for my SSD HDD which are rated to last about 5 years or a little more base on a 256gig SSD drive and given how much data I rad/write to it per day for a number of years. Will get back to you if I can find it heh.

http://ask-leo.com/how_do_i_fix_bad_sectors_on_a_flash_drive.html
 

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I had just tried to Format one of the cards using my PC and now it seems to be ok and now i have 503 available space for my photos :)
Will try the other card tomorrow.
 

Is that usually how much space you have on it for photos or less then what it use to be?
It is lesser. But ironically i just checked the other card and it seems ok already and shows the same number of available shots available 503..hmm..
 

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I had just tried to Format one of the cards using my PC and now it seems to be ok and now i have 503 available space for my photos :)
Will try the other card tomorrow.

Just to check, did you shoot until there is 0 shot left before the formatting?
 

Just to check, did you shoot until there is 0 shot left before the formatting?

No,I hardly used up the full capacity of the memory space.
 

No,I hardly used up the full capacity of the memory space.

I’m referring to the no. of shots available from the camera, because:

It may be due to the file numbering system running towards the last number.

On my camera, the number start from 100-0001 to 999-9999, a 7 digit counter.
On the CF card, the first 3 digit is at the beginning of folder name, last 4 digit at the end of filename like this:
\DCIM\999xxxxx\xxxx9999.xxx

When the counter reach 999-9998, any new formatted card inserted will show only 1 shot available. The number will reset after it reach 999-9999 by using a new blank card.

Two possibilities to get into this situation:
1. You’ve actually shoot 9,000,000 shots in this camera, or
2. A card with very high folder numbering, was used before, in this camera.

You can try this to see if it’s happening to your camera:
1. Format a new/unused card in the camera.
2. Take one shot.
3. Rename the 1st 3 digit folder name to 999, last 4 digit filename to 9998 from you computer.
4. Put the card into the camera and see how many shot available.
 

I’m referring to the no. of shots available from the camera, because:

It may be due to the file numbering system running towards the last number.

On my camera, the number start from 100-0001 to 999-9999, a 7 digit counter.
On the CF card, the first 3 digit is at the beginning of folder name, last 4 digit at the end of filename like this:
\DCIM\999xxxxx\xxxx9999.xxx

When the counter reach 999-9998, any new formatted card inserted will show only 1 shot available. The number will reset after it reach 999-9999 by using a new blank card.

Two possibilities to get into this situation:
1. You’ve actually shoot 9,000,000 shots in this camera, or
2. A card with very high folder numbering, was used before, in this camera.

You can try this to see if it’s happening to your camera:
1. Format a new/unused card in the camera.
2. Take one shot.
3. Rename the 1st 3 digit folder name to 999, last 4 digit filename to 9998 from you computer.
4. Put the card into the camera and see how many shot available.


My file numbering is most of the time 100-0000 or at most 101-0000 then I will will reset back to 100-0000.
But anyway,I tested both cards on 2 cameras and it was showing at the low side.
But now everything seems to be better but full space seems lower now.
 

My file numbering is most of the time 100-0000 or at most 101-0000 then I will will reset back to 100-0000.
But anyway,I tested both cards on 2 cameras and it was showing at the low side.
But now everything seems to be better but full space seems lower now.

No problem, just highlight some possibility.

If it’s not due to numbering issue, then how to explain your the other card which previously shows 100+ available, now shows 503 available ?
 

No problem, just highlight some possibility.

If it’s not due to numbering issue, then how to explain your the other card which previously shows 100+ available, now shows 503 available ?

Iam puzzled too. I noticed these problem on sunday at home when i had both my 7D2 and 1D4. So i swapped both cards within these 2 cameras and both cards were showing on the low end of space available(1D4 is slightly more due to its lower MP)
So yesterday I just brought up my 7D2 with one of the CF cards inside back home to do a Format on my computer,while another CF card inside the 1D4 was inside my car. So I did Format on my computer and later on insert into the 7D2 to check the available space and it showed 503.
So this morning I removed the card from 7D2 and put it into the 1D4 and swapped to double confirmed and it shows something like 550(used to be 600 plus). While I was surprised that the card from 1D4 which i replaced into the 7D2 showed 503 also. So I thought I might have mixed up and did a swapped again to check. It was indeed what it was. But if i remember correctly both cards didn't show the same number last time even though both are 16GB.
 

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Mystery unsolved.

I believe most camera don’t do write verification, you should format the card in the camera, then take unique test shot until the card is full, and check for any corruption.
 

Iam puzzled too. I noticed these problem on sunday at home when i had both my 7D2 and 1D4. So i swapped both cards within these 2 cameras and both cards were showing on the low end of space available(1D4 is slightly more due to its lower MP)
So yesterday I just brought up my 7D2 with one of the CF cards inside back home to do a Format on my computer,while another CF card inside the 1D4 was inside my car. So I did Format on my computer and later on insert into the 7D2 to check the available space and it showed 503.
So this morning I removed the card from 7D2 and put it into the 1D4 and swapped to double confirmed and it shows something like 550(used to be 600 plus). While I was surprised that the card from 1D4 which i replaced into the 7D2 showed 503 also. So I thought I might have mixed up and did a swapped again to check. It was indeed what it was. But if i remember correctly both cards didn't show the same number last time even though both are 16GB.

Not a direct answer to your situation but to bring some awareness to others who are new to this less talked about topic of memory card which we sometime take for granted.

1) The remaining frames available info from the card is estimated on the camera. The remaining frames can differ when put into another camera. It's due to choice of format like RAW, Jpeg Hi, Jpeg Lo eg, scene you shot and of course the megapixel of the camera. I think that's obvious to most right off the bat.

But that figure is just an estimation. take Turbonetics card showing 503 frames left as example. I am certain by the time he max out the card, it could show 480 or 520 shots because each frame shot is not exactly the same byte size. One with less color in the scene ( a white wall scene ) could end up taking 4.6mb (jpeg) and then you shot another with lots of colors and fine details details like a tree, that file size might be 6.1mb. So collectively at the end you could have shot more or less then 503 frames.

2) I usually don't share memory cards between my D300 and D4 in between shooting. There are compatibility issues not only between camera brands but also models at time. That means what's shot on one camera (D700) might not be previewed when put into another camera like say D3. You may see the remaining frame info (shot in the D700) but you can not preview the Images or Video. Best to check if you have old and newer cameras in your collection and see if you do have this issue. Not sure about Canon. Seem like a small issue but it can bad in some situation.

3) When the tiny BYTE switches of the memory chip nearing it's ending life span, the card's "wear leveling" ability can mask the detection of a faulty or worn out bit. Unless you constantly max the card, you hardly will notice it and think it is a glitch of some sort. And seem to have gone away after a format. This single or few thousand bit that has gone bad may show itself as some weird anomaly image like half your photo but parts of it get distorted, color run, weird artifact ..etc. This may happen more and more progressively and noticeable if you often max the card. Another system could be a bad read when you try to preview the shot or camera seem to hang while reading the card or after taking a shot.

4) Sometime those individual tiny BYTE switches can be temporary and with certain retrieval software or formatting you still might "unstuck: it. I have had some failed cards before due to wear and tear and one time possibly due to a sudden death and the card just stop working. But the worn out cards I have lasted me about 2 years plus. I always shoot to the max easily given they were 1 or 2 gig cards. I have 1 16gig cards that's coming to 3 years old and still fine but I am cautious. Over time all cards will wear out or it can just fail so take as much caution over them as you do your camera and lens.

Not to get anymore technical, Sorry if I did. Best to always mark your cards with a date on them and mark them if they have ever gave you any problem. Overtime this alert you that the card had a hiccup before and if this occur on the same card too often, it might be time to change card. I think most will not worry but for mission critical projects like Wedding, launches..etc. That is a nightmare.

Don't take them for granted.
 

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