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Old May 26, 2012, 8:04 AM   #1
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This isn't a Pentax specific question-but with all the camera knowledge in this forum I'm hoping someone has a solution. My daughter went to Hawaii on vacation. Her camera uses a CF card-she can view the shots on the camera but they will not download to the computer-any suggestions?

Thanks
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Old May 26, 2012, 8:26 AM   #2
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Are you using a card reader or connecting the camera to the PC with a cable?
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Old May 26, 2012, 10:35 AM   #3
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Quote:
Originally Posted by pboerger View Post
Are you using a card reader or connecting the camera to the PC with a cable?
Card reader-camera is in Arizona-memory card is in New Hampshire-can't make this easy
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Old May 26, 2012, 1:59 PM   #4
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Sometimes the first shot becomes corrupted .. maybe the card was not formatted in between the previous downloads and the new series of shots and this can happen (very rarely).

I've had this happen before .. on a paid shoot when all hell was about to break loose as people though the card was corrupted and all the shots with it !

I deleted the first shot and then there was no subsequent issue downloading the rest. It could also happen if you can e.g. only download the first 54 shots and no more ... it's the 55th that is the issue, delete it and the others should download with issue.

Hope this is what it causing the issue, as it's an easy fix.
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Old May 26, 2012, 2:13 PM   #5
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The file system is probably corrupted, probably because of incomplete writes to the FAT (File Allocation Table), that can happen when users don't use the "Safely Remove" icon in their Sytem Tray before unplugging a card or reader when you've written to the card in any way (and deletes are writing to it, and often users will do things like "cut and paste" images, and the "cut" part is a delete).

That's because the operating system can delay writes to a card by keeping them in the Operating System's disk cache in memory, depending on how the drivers are configured.

So, if you're doing things like deleting images (or transfer software is deleting the images) without using the Safely Remove icon before removing a card, you can easily corrupt the file system on it (because some of the pending writes to update the file system are being held in the operating system's disk cache at the time you remove the card).

That corruption may not be obvious until later either (when you start seeing issues like you're reporting your daughter has now).

With Windows (and some other operating systems), if you "right click" on the icon for a card reader under My Computer and select the "Eject" choice, that does the same thing as the Safely Remove icon (flushes any pending writes in the Operating System's cache and unmounts the file system so that the card can be safely removed). So, I'd suggest that you always do that as a safety precaution before removing any card you're accessing in a card reader.

I would not do anything that writes to the card (take any more photos, delete any photos, etc.), until you recover the images from it.

Just use the instructions in this post to download and run photorec (free) to get all of the images from the card. It ignores the underlying file system entirely and uses advanced techniques to locate files via unique information in their headers and copies them to your hard drive for you. So, it can get them even if the FAT is corrupted.

http://forums.steves-digicams.com/me...ory-cards.html

Then, after you make sure you can see all of the full size images (not just the thumbnails), reformat the card again using the camera's menu choice for format before using it again. IOW, the thumbnails are separate jpeg images embedded inside of the full size images. So, they can appear to be OK (and some cameras use them when browsing through images), even when the FAT is corrupted so that it doesn't know the correct locations of all of the blocks that make up the full size images.

So, make sure you can see the full size images OK after you recover the images to your hard drive. Then, reformat the card using the camera's menu choice for format before using it again so that it has a new File Allocation Table (which acts as an index that keeps track of where all of the separate pieces that make each file are located on the card).

Personally, I reformat my cards that way before *every*reuse (using the camera's menu choice for format, not a PC). No exceptions.

I would not trust a card that hasn't been reformatted in the camera I'm using before taking more photos after copying the last batch from it (so that I start out with a new FAT each time), as I've seen too many FAT corruption issues with users' cards over the years, and sometimes corruption issues are not obvious until you really need the images (with more serious problems often occurring when the images are really important).

That way (reformatting a card with the camera's menu choice for that purpose) prior to *every* reuse, I'm always starting out with a fresh FAT (File Allocation Table), just the way the camera expects it (since it's performing the format). That helps to reduce problems from unnoticed file system corruption.

Note that reformatting a card using a camera's menu choice for format is usually as fast or faster than deleting the images on it manually anyway, since in most cases, that's only recreating the FAT (File Allocation Table, which is an index that keeps track of the block locations that make up each image file), not overwriting the entire card.
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Old May 29, 2012, 12:36 AM   #6
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I agree, I never pull images directly from the card (SD or CF), dump the entire card to a HD and then reformat the card in camera for a fresh card to work with. I then work with the images from the HD which has always worked for me without any issues.

I find CF cards to be very touchy if you work directly from the card when processing images and many times that process will make the card unreadable.
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Old May 29, 2012, 7:47 AM   #7
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Quote:
Originally Posted by JimC View Post
The file system is probably corrupted, probably because of incomplete writes to the FAT (File Allocation Table), that can happen when users don't use the "Safely Remove" icon in their Sytem Tray before unplugging a card or reader when you've written to the card in any way (and deletes are writing to it, and often users will do things like "cut and paste" images, and the "cut" part is a delete).

That's because the operating system can delay writes to a card by keeping them in the Operating System's disk cache in memory, depending on how the drivers are configured.

So, if you're doing things like deleting images (or transfer software is deleting the images) without using the Safely Remove icon before removing a card, you can easily corrupt the file system on it (because some of the pending writes to update the file system are being held in the operating system's disk cache at the time you remove the card).

That corruption may not be obvious until later either (when you start seeing issues like you're reporting your daughter has now).

With Windows (and some other operating systems), if you "right click" on the icon for a card reader under My Computer and select the "Eject" choice, that does the same thing as the Safely Remove icon (flushes any pending writes in the Operating System's cache and unmounts the file system so that the card can be safely removed). So, I'd suggest that you always do that as a safety precaution before removing any card you're accessing in a card reader.

I would not do anything that writes to the card (take any more photos, delete any photos, etc.), until you recover the images from it.

Just use the instructions in this post to download and run photorec (free) to get all of the images from the card. It ignores the underlying file system entirely and uses advanced techniques to locate files via unique information in their headers and copies them to your hard drive for you. So, it can get them even if the FAT is corrupted.

http://forums.steves-digicams.com/me...ory-cards.html

Then, after you make sure you can see all of the full size images (not just the thumbnails), reformat the card again using the camera's menu choice for format before using it again. IOW, the thumbnails are separate jpeg images embedded inside of the full size images. So, they can appear to be OK (and some cameras use them when browsing through images), even when the FAT is corrupted so that it doesn't know the correct locations of all of the blocks that make up the full size images.

So, make sure you can see the full size images OK after you recover the images to your hard drive. Then, reformat the card using the camera's menu choice for format before using it again so that it has a new File Allocation Table (which acts as an index that keeps track of where all of the separate pieces that make each file are located on the card).

Personally, I reformat my cards that way before *every*reuse (using the camera's menu choice for format, not a PC). No exceptions.

I would not trust a card that hasn't been reformatted in the camera I'm using before taking more photos after copying the last batch from it (so that I start out with a new FAT each time), as I've seen too many FAT corruption issues with users' cards over the years, and sometimes corruption issues are not obvious until you really need the images (with more serious problems often occurring when the images are really important).

That way (reformatting a card with the camera's menu choice for that purpose) prior to *every* reuse, I'm always starting out with a fresh FAT (File Allocation Table), just the way the camera expects it (since it's performing the format). That helps to reduce problems from unnoticed file system corruption.

Note that reformatting a card using a camera's menu choice for format is usually as fast or faster than deleting the images on it manually anyway, since in most cases, that's only recreating the FAT (File Allocation Table, which is an index that keeps track of the block locations that make up each image file), not overwriting the entire card.
Thanks for all your help-but still have some problems-was able to extract the files from the card-but a lot are thumbnails-not the full files-any ideas?
Thanks
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Old May 29, 2012, 12:17 PM   #8
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Did you use the Whole Disk option when you got to a screen with that option on it, as suggested in the thread I posted about recovering images?

Note that it tends to split up the recovered files into multiple folders, too (so make sure to look in all of the subfolders it put the recovered images into).

It's not unusual to see both thumbnails and full size images recovered. So, make sure to look through all of the recovered images. I'd be very surprised if photorec was not able to recover all images that haven't been overwritten yet from most modern cameras, shooting raw or jpeg. But, note that sometimes it will show a .tiff extension for raw files (just rename them to the correct extension for your camera (.cr2, .nef, etc.) if that happens, and then your raw converter should be able to open them).

Were the images jpeg or raw? What camera model was used to take them?
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Old May 29, 2012, 3:25 PM   #9
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I always use http://www.piriform.com/recuva just set it to deep scan and obviously set the download folder to your computer as you can recover files from a card to a card.
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Old May 29, 2012, 3:48 PM   #10
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Yes. recuva is another good product.

I had "blacklisted" piriform and recvua from Steve's for a while due to spam (posts from brand new members promoting them in the forums here, from IP Addresses that were obviously being used by SEO firms (Search Engine Optimization firms that I tend to refer to as Spammers).

That way, nobody (even a satisfied customer) could post links to them. to discourage companies from making use of SEO firms for product promotion (i.e., using forums for commercial purposes, which we do not allow here).

But, because they have a good product, I recently lifted the spam filters we had in place, so that members could post links to them again. But, if I see further indications that they're using our forums for advertising again, then the filters will go back in place, no matter how good their product is, so that nobody can post links to them in our forums. That helps to discourage the use of SEO firms (a.k.a., forum spammers) trying to get more page hits for their client's sites.
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