Formatting a card

I read something in Outdoor Photography about formatting a card after every use. Now I just read if you format to often it looses memory? Whats the real story on formatting cards?

Where did you read that it loses memory if you format too much? I format, in camera, and have never noticed any memory loss.

I must have formatted my brain too many times

Can't remember whether I formatted or not.

Ive formatted my card countless times and it still reads the same remaining pics available. I suppose too much formatting might cause some fragmentation, but on the T3i there is low level formatting (I assume others have this too) and that will clear everything.

First ive heard of memory loss

A controversial subject and the choice of answers answer has changed over time.

The "erase all" function on your digital camera was once considered to not be permanent in that standard Windows or MAC tools could recover the images. Formatting was considered to be permanent loss of data. But in the last few years the better memory manufacturers have provided very good software tools that can recover images, even from a formatted card. Sandisk for instance on the better grade cards includes the ability to download and use RescuePro, a very good recovery tool.

At a recent "school" a professional clearly stated always format in camera as that sets up a preferential file structure for that camera. This becomes even more important if you loan out cards. If someone borrows a card and uses it in a NIkon, then you attempt to use it in a Canon, you might have corrupted images. It takes about 5 seconds to format my 16 GB card so the occasional argument of formatting taking more time also isn't valid.

I format after every use to clear the last images. All my cards still hold the same amount. This is the thing that drives me crazy about the internet, anyone can write anything no matter how bad its information is. Kudos for trying to ascertain the correct answer.

Yes, I format in my camera just before using a card. Although I don't loan out or trade cards between different cameras, formatting the card in the camera just before use is a last check that the card controller is performing properly (when a card fails, it is most a controller failure). This is, however, the equivalent of a "quick format" done in the computer.

Some card manufactuers have recommended an occasional (once or twice a year) "full format" in the computer followed by a camera format to more thoroughly test the card controller. (There is no "low-level" formatting done anywhere. There might be some esoteric utilities available on the Internet that claim to low-level format a memory card, but that's not done by Windows or by cameras.)

There's probably no harm to "erase all," except that it's a tad slower than doing a format in camera and doesn't run the controller quite as well as either a "quick format" or a "full format."

Neither the quick format (camera or Windows) nor the full format (Windows) actually writes to the memory registers--that's why it's possible to recover data after formatting with the appropriate utility. That's also why those formats does not "use up" the memory lifespan.

In practice, though, I don't think anyone has ever "used up" card memory before losing or discarding a card. The signs of that would be steadily decreasing capacity.

I format after every use to ensure the card is good before its next use. In terms of reducing its working life I consider cards to be expendable items with a finite life so I would more that likely replace a card after a few years use. Just like a HDD in my computer it is better to change it early rather than risk a failure and loose precious images!

Neil

Yes everytime you format your cards it looses memory.
Memory of everything that was previously recorded on it

MJEXP wrote in post #15154161
I read something in Outdoor Photography about formatting a card after every use. Now I just read if you format to often it looses memory? Whats the real story on formatting cards?

When I want to delete all content from an SD card I will usually low level format it. But you don't have to do it every time you use the camera. I don't necessarily want to delete everything from the card even if I've already downloaded the files to Lightroom. Generally most folks believe formatting is a better way to clear your card rather than just deleting all the files.

Just to readdress this issue:

The memory registers do have a finite number of read/write cycles, but very few users are likely to reach that number.

Current cards using NAND flash are rated for 1,000,000 writes per block before hard failure

In addition, modern controllers use "wear leveling" algorithms so that no one (or group) of registers gets used more than others. Like rotating tires, the controllers spread the writes over all the registers so that as far as "wear" is concerned, you'd have to completely fill the card 1,000,000 times to "wear it out."

Formatting doesn't even write to the registers, so there really isn't any wear at all from formatting. Both formatting and erasing do writes to the File Allocation Table, but those are rated for 1,000,000 cycles as well.

Bottom line: In the discussion about whether to format or to erase, wear is not a relevant factor.

I always format cards in camera before any shoot providing all previous images have been downloaded and backed up. You only make that mistake once!

This ensures I have full capacity of the card available and when it comes to downloading you are not wasting time on unwanted images.

I tutor a lot of youngsters and always warn them about deleting images to make room on a card. This can lead to fragmented images and the good old Error 6 and fun and games trying to retrieve images.

I also always format my card. I feel like using a fresh, clean memory card is safer than just deleting and then shooting. For some reason I'm always paranoid that if I don't format it, then whatever I couldn't delete on the card because I didn't format it, will do something to the card and possibly ruin the images/make them unreadable. Even if it does delete memory eventually, (which seems odd to me) I'd rather have that than miss images!

I've been shooting digital for about 8 years now and was using it to a lesser degree as long as 15 years ago.... Am currently using 14 8GB UDMA CF cards in my 7Ds, plus a couple 16GB UDMA that I primarily use in my 5DII (but occasionally see use in 7Ds when everything else is full). In addition, I've still got a few dozen smaller, slower CF cards around and some SD cards for a couple compact P&S cameras that use them.

Every time I insert a card in camera, I format it. Period. I take between 50,000 and 100,000 images a year, so some of my cards have probably been formatted hundreds of times now. ANd some have been used in a variety of cameras over the years. None of them have ever given me any problems what-so-ever, that I would even remotely link to the formatting process. So I think it's bunk that there can or will be losses from doing that.

In fact, I think not formatting is far, far more likely to cause issues. For example, the latest firmware updates for 7D emphasize it's important to format the card afterward, which removes old file formats and writes new ones. People who had trouble with the 2.x.x firmware installation almost all seemed to not have followed those instructions (which also said to turn the camera off and remove the batteries for at least 2 seconds, but that's another matter).

The only format related issue I can recall ever having was when someone borrowed a card and used it in a Nikon. After they returned it, I couldn't access the card or even format it in my Canon. I had to format it in computer and then again in camera, before it would work again. After doing that, it was fine.

Formatting is mostly non-destructive. All it does is mark old files as okay to write over. That's why it's possible to recover images from a formatted card, But that's not always 100% successful... some may still be lost when overwritten by the formatting installing new folders... or if any new images have been recorded on the card.

Formatting configures the card to be ready for use in the camera, with the right file structure, folders, etc. That's why formatting in the computer is not generally adequate by itself and it's so important to follow up formatting it in camera. Or just do your formatting in camera alone. That will usually be fine. After removing or copying off any images you want to keep, of course.

The only other major card-related issue I had was when I removed one too quickly, while the last batch of images were still being written to the card. I had to run a recovery program on it to retrieve any of the images, and lost not only some of the ones in the last burst, but about a third of the images on the card. Still, I was able to retrieve about 2/3.

Format... in the camera... every time you insert a card. It will do no harm.... most likely does a lot of good!