Question for computer savvy Brassgogglers

[J. Wilhelm]

I have a very particular problem. I'm trying to recover data (images) from a micro SD card that was inside a smartphone. The card was formatted in FAT, not as an internal Android card.

The card was shared between 3 smartphones as an archive of sorts, and as I purchased a new phone, the card would get transferred to the new phone. I'm aware there was a risk of accidental reformatting by each smartphone, but I was always very careful to eject the card properly each time the card was removed from the phone.

A few days ago, I dropped my phone (didn't break) but I noticed that the card was showing as empty. I rebooted the phone and I saw the data was back, so I assumed there was no problem.  But the next day the card again showed no data and Android notified me there was a problem with the card, prompting me to choose what format I wanted for the "new" card.  I knew I was in trouble.

I tried rebooting the phone again, but this time the data was lost. Android showed the card was empty and wrote a "LOST" directory (empty) which suggested it has reformatted the card.

Now my Linux computer can't even recognize the media, so I can't even mount it (it doesn't show up on /dev so I can't link it to /media, even). My guess is that Android formatted it as an "internal" card.

At this point I'm wondering if I have to use Android in my last phone to reformat the card, just so that other computers can detect the card, and then I can use some rescue package. I'm also wondering I
if formating in Linux ext3 would be better (probably not).

I've rescued erased images using a Linux package before -with success, but not from a card with a damaged file system.

Any thoughts or suggestions?

[Sorontar]

I'm afraid that I can't advise you on this. I have had issues like this before with data or directories from one old device not being readable, but until I got something to recognise the drive, I was lost. Sometimes I had the (database) data, but the software required to recognise the format was too out-of-date that I couldn't install it.
Sorry.

Sorontar

[RJBowman]

This is from the little bit of knowledge that I have of SD cards:

It's possible that a part of the drive that contains the index of files got corrupted, but data on other parts of the drive are intact. An expert may be able to comb through that data to figure out how the files were formatted and recover them. It's likely to cost some money.

[J. Wilhelm]

I'm afraid that I can't advise you on this. I have had issues like this before with data or directories from one old device not being readable, but until I got something to recognise the drive, I was lost. Sometimes I had the (database) data, but the software required to recognise the format was too out-of-date that I couldn't install it.
Sorry.

Sorontar

This is from the little bit of knowledge that I have of SD cards:

It's possible that a part of the drive that contains the index of files got corrupted, but data on other parts of the drive are intact. An expert may be able to comb through that data to figure out how the files were formatted and recover them. It's likely to cost some money.

Indeed, in theory the amount of data lost to indexing is minor relative to whatever is stored.

I reformatted the card to see if I could recognize it elsewhere.  But even after reformatting, only my smartphone can read the card. I can access with my computer only if the cellphone is connected to my computer. That's not true for any other card. This implies some sort of further damage to the card that I didn't know about.

The data is on the order of 20 GB, and not all of it is lost forever, like copies of school notes, past college projects, movies and music dating to the 1990s, which were actually copied from my hard drives to a tablet just as reading material, before I bought my first true smartphone. Then I archived the original 2GB card and passed it to a 32 GB micro SD card which I shared between the three smartphones I've had since. But there will be about 5 or 8GB of material created between 2018 and today, mostly photos, and that will be a total loss, only backed up by whatever selections I posted on social media in reduced resolution (Twitter reduces the size of photos substantially).  There's not much on DeviantArt, but those will be full resolution photos. The thought of scavenging through my Twitter's decade old archives just for low resolution pictures gives me the heebie jeebies. But it's technically possible. 

It's much easier to download from html copies of Brassgoggles and from DeviantArt directly, and a little bit from Pinterest as well. The Pinterest pictures might be in full resolution too. Anything before 2017 can be assumed to be safe, though, because I mostly used the computer, which I restored along with 3 oldschool hard drives.