No, I meant just to delete all movies/still images at one time.

Mind you, you must avoid formatting your memory card as much as possible (meaning no reformatting every time you simply want to delete data or free space on the card).

As a matter of fact, every flash memory card does wear down (and cheap cards tend to wear the first few bit the most, while the last bit go almost unused). Formatting/reformatting operation merely increases pace of such deterioration.

Is that right Arkady - that reformatting reduces the card's life-cycle? I've never heard of that before, so is this common knowledge? But doesn't a reformatted card present the camera with a 'clean sheet' with no defragging needed, so to speak?

tom.

Hi, Tom

Here are you questions and my answers.


1. Is that right that reformatting reduces the card's life-cycle?

A memory card, based on the flash non-volatile storage technology, stores information in an array of memory cells made from floating-gate transistors, so that each cell stores only one bit of information. A single-level flash cell in its default state is logically equivalent to a binary "1" value.

During reformatting process, each cell of a memory card is erased. To erase a flash cell (resetting it to the "1" state), a large voltage of the opposite polarity is applied. Unfortunately, this can be done only a finite number of times. In technical terms, flash memory has a finite number of program-erase cycles (typically written as P/E cycles).

2. But doesn't a reformatted card present the camera with a 'clean sheet' with no defragging needed?

It’s not necessarily so. Fragmentation happens when you delete one or more clips surrounded by others and then start to recode a new clip. Trying to save free space on the card the camcorder processor may split a new clip into parts filling up the gap.

To avoid this, do not delete particular clips but erase them all.

3. Is this common knowledge? Yes, Tom, it is. Memory wear is the known limitation of flash memory technology.

Thanks for your answers Arkady. You learn something new every day, and it's this that makes life so interesting.

Will this card work fine? I bought four.

Ebay Item number: 120609547882

I don't mean to throw salt on anyone's wounds, but this question came up many times on DPReview forums, and it's been actually cleared that you don't kill free memory flash space by reformatting, this is a simple experiment that takes 2 minutes to open chat windows from two major player's websites.

Sandisk's response about reformatting:

Keith B.: Hello, thank you for contacting SanDisk. My name is Keith B.. Please give me a moment while I look into your question.
KC Kennedy: Good afternoon, I have a question regarding formatting and space on SDHC memory cards. Could you please, verify something for me?
Keith B.: Please tell me what is written on the face of the memory card?
KC Kennedy: A much more knowledgeable friend of mine told me that the more I format my SDHC card, the less free space I get after each formatting. Is this correct?
KC Kennedy: This is just a general memory question, I own many SD cards...
Keith B.: Ok.
Keith B.: This is not correct but formatting will delete all the data saved on card and the available space will remain the same even if you format it number of times.
KC Kennedy: may I refer to the original source?
KC Kennedy: Here are you questions and my answers.


1. Is that right that reformatting reduces the card's life-cycle?

A memory card, based on the flash non-volatile storage technology, stores information in an array of memory cells made from floating-gate transistors, so that each cell stores only one bit of information. A single-level flash cell in its default state is logically equivalent to a binary "1" value.

During reformatting process, each cell of a memory card is erased. To erase a flash cell (resetting it to the "1" state), a large voltage of the opposite polarity is applied. Unfortunately, this can be done only a finite number of times. In technical terms, flash memory has a finite number of program-erase cycles (typically written as P/E cycles).

2. But doesn't a reformatted card present the camera with a 'clean sheet' with no defragging needed?

It’s not necessarily so. Fragmentation happens when you delete one or more clips surrounded by others and then start to recode a new clip. Trying to save free space on the card the camcorder processor may split a new clip into parts filling up the gap.

To avoid this, do not delete particular clips but erase them all.

3. Is this common knowledge? Yes, Tom, it is. Memory wear is the known limitation of flash memory technology.
Keith B.: Please allow me a minute.
KC Kennedy: sure, I appreciate your time and effort
Keith B.: According to the information mentioned above you can say you have the certain numbers of read/write cycle on a flash memory card. The information provided by you do not indicate that formatting the card will have a impact on available space but to a very minimal extent it will have a impact on life cycle of card.
KC Kennedy: Thank you, Keith
Keith B.: Have I provided you with all the required information, today?
KC Kennedy: Yes, Sir. Absolutely, have a great day.
Keith B.: Is there any thing else I may assist you with?
KC Kennedy: not any longer, thank you
Keith B.: We'll send you the incident number that you can use to reference this chat, and also, the chat transcript in a follow-up email. Thank you.
Keith B.: Thank you for contacting SanDisk, and you have a great day, KC.
Keith B. has disconnected.

LEXAR's REPLY:

Welcome to Lexar Media's Live Chat. A Live Chat agent will join you in a moment... Please do not begin typing until you have been connected to an agent.
Hello, my name is Sathya . How may I help you?
KC Kennedy: Good afternoon, I have a question regarding formatting and space on SDHC memory cards. Could you please, verify something for me?

KC Kennedy: A colleague of mine mentioned that the more often you reformat SDHC memory card, the less free memory you get on it. Please, verify if this really is the case
Sathya : No, it is not like that.
KC Kennedy: please, explain
Sathya : For example if you are using 4 GB SDHC card the actual space you will get approximately 3.73 GB the remaining space would be allocate to inbuilt memory on your computer OS.
Sathya : Normally formatting will erase bad sector and if any data in your memory card.
Sathya : And it will reset the memory card to original factory settings.
KC Kennedy: So, formatting card completely even 100 times will still make that same 3.73gb of free space available for recording?
Sathya : Exactly.
KC Kennedy: thank you very much, have a great day
Sathya : You are welcome.
Sathya : Is there anything else I can help you with?
KC Kennedy: no, Sathya, thank you for your help
Sathya : It's my pleasure to assist you.
Sathya : If there is nothing further I can assist you with, I’d like to thank you for visiting Lexar..com. Have a great day.

I don’t mean to turn this chat into a theoretical conference but to verify that the memory wear exists as a real fact of life would take you even less than 2 minutes if you bothered yourself to open Wikipedia website in the first place instead of websites of memory card manufactures.

There you would learn that flash memory does wear down, and cheap cards tend to wear the first few bit the most, while the last bit go almost unused.

To prevent this high quality cards use what is known as "wear leveling" to remap the starting point, resulting in a more even wear pattern. Sure this mechanism works, and you cannot kill your card even after hundreds of reformatting cycles.

But also without a doubt in the long run the less you reformat your card the longer it will last.

Ok, next time I'll go to the first source, Wikepoedia (source without an author).

How about this?

Wear Out

Another peculiarity of NAND Flash as a storage medium is its increasing susceptibility to bit errors after having gone through a certain number of program-erase (P/E) cycles. The number of cycles varies, depending on density (storage capacity per physical area), vendor, and NAND Flash type.

That was an exact quote from the paper titled “NAND Flash Solid State Storage for the Enterprise: An In-depth Look at Reliability, April 2009” written by Jonathan Thatcher (Fusion-io), Tom Coughlin (Coughlin Associates), Jim Handy (Objective-Analysis), and Neal Ekker (Texas Memory Systems).

Is this better than what you called no-name source?

Yes, you are right. Now I know I was wrong :)

Ebay Item number: 120609547882

Sure thing cards turned out to be fake, from serial numbers (all four have the same #'s), to wrong packaging, wrong color of the card, fake holograms, fuffer overflow at highest quality recording...).
Very sad, and seller claims that I don't know how to use memory cards. Sure thing negative feedback will follow as soon as I get my PayPal refund.

Who has lowest priced Class 4 cards in 16-32gb range now?