Possible SD Card Corruption ?

retiredfromlife

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Not sure if this is an SD card problem or something I did.
This is from a EM10 Mark II. I noticed I selected a lot of images for protection with the little key in the upper right of the preview frame.
After removing these I went to download the images to my PC via the cable and noticed the below.

I ended with with a lot of those 4 KB files starting with ._ These are the the directory 100OLYMP along with all the other photos
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From what I can see all my images are there, but they have been there for so long I doubt I would remember any that are corrupted.

Upon looking at the SD card file structure compared to me EM1.3 I noticed the below differences.
The carriage returns in the shots are from the Word document I pasted the SD card screen shots into.
I notice the image share and wonder if I had also selected images to share some how, if that is so could those 4KB files from that?

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Has anyone seen these files starting with ._ and know what they are or mean. And if I can get rid of them without formatting the card.

Would be nice if it was me who caused the problem what it was to try and avoid it in the future.
 

c0ldc0ne

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Apparently, you have used this card in a Mac at some point, as these are MacOS generated files/folders. All these can be deleted safely, and are perfectly harmless much like the thumbs.db files that Windows creates.
 

retiredfromlife

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Apparently, you have used this card in a Mac at some point, as these are MacOS generated files/folders. All these can be deleted safely, and are perfectly harmless much like the thumbs.db files that Windows creates.
That would explain it, I did try to look at then in ON1 on an iMac
I forgot that when my daughter used a mac at school if left junk files on all removeable media.

Wonder why macs do that
 

c0ldc0ne

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Wonder why macs do that
For the same reason that Windows creates the thumbs.db file: to store OS specific metadata. The files are hidden from view on native operating systems (you won't normally see a thumbs.db file on a Windows machine, but viewing the same volume from a Mac will show them and vice versa for the ._ files).

Macs normally store this metadata in the extended attributes of its native (HFS) filesystem, but will fall back to ._ files for non-native filesystems, such as SMB/CIFS network shares or, as in your case, SD cards which are generally formatted using FAT32.
 

BrianLa

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SD corruption is what I blame when when my pictures don't come out as well as I hoped. 🤣
Brian
 

retiredfromlife

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MIght be worth re-formatting the card. You can do this in-camera.
Will definately do this but wanted to check if there a possibility of any files I may need to try and recover. At least I know what happened now.
So I guess all Mac users must get these files.
 

retiredfromlife

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For the same reason that Windows creates the thumbs.db file: to store OS specific metadata. The files are hidden from view on native operating systems (you won't normally see a thumbs.db file on a Windows machine, but viewing the same volume from a Mac will show them and vice versa for the ._ files).

Macs normally store this metadata in the extended attributes of its native (HFS) filesystem, but will fall back to ._ files for non-native filesystems, such as SMB/CIFS network shares or, as in your case, SD cards which are generally formatted using FAT32.
I normally format my SD cards in the camera. This happens very quickly so I wonder if this is a full format or just some change to the directory table or something.
Is there a way to format them so they work in camera and Mac to avoid these files?
 

BosseBe

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Is there a way to format them so they work in camera and Mac to avoid these files?
Simple answer, probably not! (Or just No!)

The camera and the Mac has different OS's so they will do whatever they want. This was not thought trough, ignore it.

The equally simple solution is to never look at the pictures or do anything with them in your computer as long as they are on the card, just transfer all the pictures/files to your computer before looking at them or doing anything else.
The storage in your computer is probably huge compared to the card so just dump everything and then look and sort (it is also probably faster).
 
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BosseBe

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Another possibly dangerous solution, is to Write Protect your card before connecting it to the computer, now nothing can be written to the card!
(I say dangerous because if you forget to reset the Write Protect switch on the card, your pictures will not be saved!)

That Write protect switch is the only movable mechanical thing on SD cards, and it can cause so much problems! They should really get rid of it!
 

BosseBe

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My approach is to get the card out of the camera, put it in the SD card reader and the copy the pictures that have been taken since my last save into a directory on the computer (PC).
After they have transferred I dismount the card (Eject it with right click, whatever it is called in English) and take it out of the reader and put it back in the camera.
Once in a while I will do a complete copy of the pictures on the card to the PC and reformat the card in the camera.
I keep this copy for a while and delete it after determining that I haven't missed any picture.
(Actually this rarely happens, the files just stay there until I need more space and then I might delete them. :dash2:)
 
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