The right way to delete all photos from a camera

Question

What is the most correct way to delete all photos from a camera after they all have been copied to a computer:

• to format memory card using the camera menu,
• or simply Select All and Delete photo files from the card using a computer as if it would be just a usb flash drive,
• or maybe some other way?

Or no difference at all?

Answer 1

There's no "right" way to do this, it's what works best for you. In general, I just tend to do the "delete all" unless the card is quite full, then I may format. It's just a question of speed, I'll tend to use the fastest path to clearing it off.

Now, there are some that recommend regular formatting of the card for various reasons. I'm not in that camp, the basis for it isn't entirely sound. However, the upside is the detection of potential hardware flaws on the device. So, even if it isn't specifically regular, doing it every now and then may have some use.

Either way, I only do it after I've made two successful copies (primary and backup). I've lost images in the past by not being more careful about it, so now I take a little time to be sure.

Answer 2

I'm not sure that the effects would be different but I would say the safe bet is

'Format the memory card using the camera menu'

Just make sure you have all of the pictures saved elsewhere before you do this (accidentally wiping out photos sucks)

Answer 3

1. Read your camera's manual. They usually have recommendations.

2. Eliminate human error. Card errors of any type are much, much more more rare than you just messing up.

The format used on cards has been a standard for a long time, and modern sizes are such that what metadata or hidden files a computer might leave are pretty insignificant. If you can find a method that keeps you from screwing up and deleting stuff by accident, then the most you'll likely need to do is a periodic in-camera format, just to be on the safe side.

I'd also add another option to the list, which is letting some sort of image-library management software take care of clearing the card for you; sort of midway between the camera and treating it like a generic USB stick. I believe Lightroom has an option for this, as does Image Capture and iPhoto on the Mac.

Answer 4

If you use your cards in different cams you'll notice that quite a few cameras only show pictures took with this one camera.

So if you chose "delete all" it will only delete those images it knows, made by the cam itself and you'll end up with a partly filled memory card, not being able to take as much pictures as it should.
Same if you sometimes have other files on your memory cards, which eat up space.

Another thing, if the file system ever got corrupt for any reason, delete all won't fix it, while format will fix logical file system corruption.

I'd always use format. Except maybe if the format is extremely slow, taking several minutes (like it was in the Leica M9, not sure if they fixed it by now).

Of course, in case of format everything is gone which, for me, is what I want, but if you tend to put important data or pictures on a memory card without having a backup somewhere else, might not be what you want (but you would not do that, would you).

Answer 5

Files stored on a memory card are organized in much the same way as a computer hard drive, and can become fragmented over time. Although the effects of fragmentation are much less significant for flash memory than it is for a mechanical hard drive, I would still recommend reformatting, at least periodically.

Answer 6

Flash cards generally are limited in the number of writes rather than the number of reads (as in the MTBF is a function of writes not reads). Formatting a card is a much "cheaper" operation (in terms of writes) than deleting all the images, so it's possible that formatting the card rather than deleting may help prolong the life of your card, although in the grand scheme of things, who can really tell.

Answer 7

Erasing rather than formatting will let you use a tool like photorec to recover photos off your memory card, should the need arise.

I've erased a card thinking I'd copied photos over, but actually hadn't, and photorec came through and recovered them for me. If I'd formatted, I'd be SOL.