SD cards (Page 3): Even if the card got wiped clean because of a strong magnetic field it should be alright after a format. The format resets the file structure to default status.

10MPlayer Loc: California

TriX wrote:

Short of the magnetic field of an MRI, I don’t believe NAND flash memory, which includes SD cards, is degraded by magnetic fields, but if you have different information, please post the reference.

Even if the card got wiped clean because of a strong magnetic field it should be alright after a format. The format resets the file structure to default status.

James Slick Loc: Pittsburgh,PA

OddJobber wrote:

When this came up here a couple of years ago, I tested it. I have a magnetic "nail sweeper", used to pick up stray hardware. I put an SD card on the magnet and left it for 10 minutes. No loss, no corrupted files, and that card still works!

Yep, Unless a alternating magnetic field is strong enough to shake the internal apart connections mechanically, it should have no effect on any flash storage device, Unlike HDDs or floppys, they do not use magnetic changes to store data. A steady magnetic field (of any strength) should have zero effect. It's not how flash storage works. A stray static electricity shock would me more relevant to flash storage.

TriX Loc: Raleigh, NC

James Slick wrote:

A stray static electricity shock would me more relevant to flash storage.

Indeed. Static electric charges can cause long-term degradation of junctions even if the device isn’t immediately destroyed. I’m terms of data corruption (flipped bits), particles from cosmic rays can be a culprit. We don’t see that as often because ECC often corrects the error before we see it, but in long running models on supercomputers, it has been shown to affect the outcome substantially in the past (data bits being flipped in the disk cache and main memory) prior to the utilization of widespread parity checking on reads.

James Slick Loc: Pittsburgh,PA

TriX wrote:

Indeed. Static electric charges can cause long-ter... (show quote)

PS I'm sorry for any incorrect grammar and spelling, as I'm at a bar watching the Dolphins and Patriots game, LOL! (damned touch screens!) 😉👍

14kphotog Loc: Marietta, Ohio

I have a SD card I use all the time, have done 30K plus shots on it, run it through the washer and dryer twice, still NO Failures.

canondave1 Loc: Houston, TX

baileygiz1 wrote:

I have a question for all the professionals out there, after some time should you replace SD cards?
Do they go bad after a period of time?

I've been using my SD 16gB card for about three years now with no problems.

Silverman Loc: Michigan

baileygiz1 wrote:

I have a question for all the professionals out there, after some time should you replace SD cards?
Do they go bad after a period of time?

Here is a link to the Memory Card Case that I bought a couple of years ago. Very Good quality, Memory cards stay Safe & Secure.

https://www.bhphotovideo.com/c/product/1047735-REG/ruggard_mch_sd12b_hard_memory_card_case.html

aphelps Loc: Central Ohio

OddJobber wrote:

When this came up here a couple of years ago, I tested it. I have a magnetic "nail sweeper", used to pick up stray hardware. I put an SD card on the magnet and left it for 10 minutes. No loss, no corrupted files, and that card still works!

I was referring to alternating current based electromagnetic fields. Constant magnetic fields like a permenant magnet will not induce electric currents unless there is motion.

aphelps Loc: Central Ohio

I was referring to alternating current magnetics. Constant permanent magnetic fields will not induce electric fields without movement. Therefore, it would be a good idea to avoid AC electro-magnetic fields like MRI imagers, large motors and wireless charging pads.

TriX Loc: Raleigh, NC

aphelps wrote:

I was referring to alternating current magnetics. Constant permanent magnetic fields will not induce electric fields without movement. Therefore, it would be a good idea to avoid AC electro-magnetic fields like MRI imagers, large motors and wireless charging pads.

The internal leads in an SD card are so short, my thought is that it would take a magnetic field in the order of a 1-2 Teslas or so (an MRI machine) to generate a substantial induced current in the internal leads, BUT the magnetic field in an MRI isn’t alternating.

James Slick Loc: Pittsburgh,PA

TriX wrote:

The internal leads in an SD card are so short, my thought is that it would take a magnetic field in the order of a 1-2 Teslas or so (an MRI machine) to generate a substantial induced current in the internal leads, BUT the magnetic field in an MRI isn’t alternating.

If that's the case (and I know MORE about nuclear reactors than MRI!) than even an MRI magnetic field should have no effect on flash memory (SD cards,for example.)

James Slick Loc: Pittsburgh,PA

brooklyn-camera I wrote:

I shoot a 7D MKII and it has SD and CF....If shooting something that I want to keep I shoot both cards just in case one should go bad, you never know.

Doing such "mirroring" is good insurance beyond the potential of flash memory failure, It reduces HUMAN failure. WE (Humans) screw up more data than our machines! 😂

James Slick Loc: Pittsburgh,PA

Silverman wrote:

Here is a link to the Memory Card Case that I bought a couple of years ago. Very Good quality, Memory cards stay Safe & Secure.

https://www.bhphotovideo.com/c/product/1047735-REG/ruggard_mch_sd12b_hard_memory_card_case.html

Yes, some sort of case is vital. Small things are to easy to misplace!

James Slick Loc: Pittsburgh,PA

10MPlayer wrote:

Even if the card got wiped clean because of a strong magnetic field it should be alright after a format. The format resets the file structure to default status.

Always format SD cards in the intended device (Camera, Audio Recorder, Phone) when installed, Any problem with cards will be reported as an error then and there, on the device. It's a slower but more certain way than formatting every card on a PC. (Is that OCD? I dunno!, But it hasn't failed me yet!😉).

James Slick Loc: Pittsburgh,PA

aphelps wrote:

I was referring to alternating current magnetics. Constant permanent magnetic fields will not induce electric fields without movement. Therefore, it would be a good idea to avoid AC electro-magnetic fields like MRI imagers, large motors and wireless charging pads.

I'm not sure if a charging pad would induce enough current to worry about, but Hellz bellz, why chance it? 😉