on box 512mb in menu display 487mb?

[MrSleep]

on my Canon A95 with the supplied 32mb CF Card displayed 30.2 which is acceptable.

But on my new 512mb Transend 45X Compact Flash Card it displays 487mb, missing 25mb, whats going on here?

[LoveOfSelene]

on my Canon A95 with the supplied 32mb CF Card displayed 30.2 which is acceptable.

But on my new 512mb Transend 45X Compact Flash Card it displays 487mb, missing 25mb, whats going on here?

The card itself is 512mb, but after formating you only get 487mb. Usually after formating, you only get around 94-95% of what the card accualy says it can hold.

Example: So if you have a 1024mb card, it should show up as ~972mb on the camera.

MB of what card says = X
X times .95 should equal the amount of space you can accually write on.

Hope this helps.
~loveofselene

[MrSleep]

10Q :p loveofselene

[ktixx]

The card itself is 512mb, but after formating you only get 487mb. Usually after formating, you only get around 94-95% of what the card accualy says it can hold.

Example: So if you have a 1024mb card, it should show up as ~972mb on the camera.

MB of what card says = X
X times .95 should equal the amount of space you can accually write on.

Hope this helps.
~loveofselene

Actually, from my knowledge (and please correct me if I am wrong) the missing space isn't actually due to formatting. All formatting really does is put a small table of information on the memory card that will tell the data where to be stored. Basically When a manufacturer says 512MB they say that 1MB = 1000kb and 1kb = 1000 bytes (They use increments of 1000). The camera, or any other computer device out there actually sees 1MB as 1024KB and 1KB as 1024 Bytes (1024 is actually correct - when you take a 2MB picture you are taking a picture that is 2,048 KB). So when they say a card is 512MB they are saying the card is 512,000kb which is equal to 512,000,000 Bytes ((512MB *1000) *1000) but when the camera sees it they see the memory in the correct increment of 1024, so that 512,000,000Bytes converted to KB is 500,000KB (512,000,000 / 1024) then convert that to MB is (500,000 / 1024) which equals 488.28 MB, that is where your 487MB comes from, maybe you will loose 1MB at most (which apparently you have) from the table and the folders that have to be stored on the card, but honestly the 512MB label is just a lie by the manufacturers. You will consistently see this with any form of media, it has nothing to do with the card, or the company you bought it from. For example, take a look at your computers hard drive, if the box says you have a 40GB Hard drive, in actuallity you only have approximately a 37GB HD. (see below for calculations)

----------------how the manufacturers see it (1000)-------------
40gb *1000 = 40,000MB
40,000MB * 1000 = 40,000,000KB
40,000,000KB * 1000 = 40,000,000,000 Bytes
----------------how the computer sees it (1024)-----------------
40,000,000,000 Bytes / 1024 = 390,62,500KB
390,62,500KB / 1024 = 38,147MB
38,147MB / 1024 = 37.25GB

Ken

[LoveOfSelene]

Actually, from my knowledge (and please correct me if I am wrong) the missing space isn't actually due to formatting. All formatting really does is put a small table of information on the memory card that will tell the data where to be stored. Basically When a manufacturer says 512MB they say that 1MB = 1000kb and 1kb = 1000 bytes (They use increments of 1000). The camera, or any other computer device out there actually sees 1MB as 1024KB and 1KB as 1024 Bytes (1024 is actually correct - when you take a 2MB picture you are taking a picture that is 2,048 KB). So when they say a card is 512MB they are saying the card is 512,000kb which is equal to 512,000,000 Bytes ((512MB *1000) *1000) but when the camera sees it they see the memory in the correct increment of 1024, so that 512,000,000Bytes converted to KB is 500,000KB (512,000,000 / 1024) then convert that to MB is (500,000 / 1024) which equals 488.28 MB, that is where your 487MB comes from, maybe you will loose 1MB at most (which apparently you have) from the table and the folders that have to be stored on the card, but honestly the 512MB label is just a lie by the manufacturers. You will consistently see this with any form of media, it has nothing to do with the card, or the company you bought it from. For example, take a look at your computers hard drive, if the box says you have a 40GB Hard drive, in actuallity you only have approximately a 37GB HD. (see below for calculations)

----------------how the manufacturers see it (1000)-------------
40gb *1000 = 40,000MB
40,000MB * 1000 = 40,000,000KB
40,000,000KB * 1000 = 40,000,000,000 Bytes
----------------how the computer sees it (1024)-----------------
40,000,000,000 Bytes / 1024 = 390,62,500KB
390,62,500KB / 1024 = 38,147MB
38,147MB / 1024 = 37.25GB

Ken

hummm interesting ken.

" All formatting really does is put a small table of information on the memory card that will tell the data where to be stored. " but where does the table go.

i get my conclusion because if you "nuke" (nuke as in completely wipe everything off, even formating, using Department of Defence Nuking program, you prolly can get offline but i got mine from fellow IT guys) a hdd or an memory card. the computer will see it as how much the device says it can really hold.

Example: 80gb hdd will show up as an 79999kb unformating disk
but after you format the drive it will show up as gigs less

~loveofselene

[MrSleep]

Thanks fellas..., That was very informative. ;)

[ktixx]

hummm interesting ken.

" All formatting really does is put a small table of information on the memory card that will tell the data where to be stored. " but where does the table go.

i get my conclusion because if you "nuke" (nuke as in completely wipe everything off, even formating, using Department of Defence Nuking program, you prolly can get offline but i got mine from fellow IT guys) a hdd or an memory card. the computer will see it as how much the device says it can really hold.

Example: 80gb hdd will show up as an 79999kb unformating disk
but after you format the drive it will show up as gigs less

~loveofselene

Took me a while to find outside of other forums..but here is a reliable source, pay specific attention to the "Clash of two worlds" part of the information.

http://en.wikipedia.org/wiki/Kilobyte

Hope this clears it up