Format 512MB but only getting 487MB

[AirEOS]

As the title states when i format my ScanDisc 512 card it says only 487MB on card in my 300D....any know how i can get that extra 25MB back please...

Regards AirEOS

[bolantej]

i think that's how all of them work. same with pc hard drives. part of the drive has to be taken up by the format/folder info, or something like that. sorry for the "uneducated" information. ;)

[robertwgross]

Yes, 487 MB sounds about right.

If you don't believe that, then do a complete format of the CF card in the computer. See what that reports. Then move the CF card to the camera and quick format it there. That makes some folders and files, and it will leave you with about 487.

---Bob Gross---

[jfrancho]

Some space needs to be used for the file system data. There is 510,918,656 bytes free to write which equals 487 MB free space for user files.

[SkipD]

The biggest reason for the number difference is this. Hard drive and memory card manufacturers like to advertise the biggest size they can to get you to buy their product. Therefore, they tell you how many megabytes their product has by dividing the total by 1,000,000 (making a "mega" equal one million in their minds). In the computer world, however, a megabyte is NOT a million bytes, but 1,048,576 bytes.

The computer is using a binary counting system. 1 kilobyte is 1024 bytes. A computer megabyte is 1024 x 1024 kilobytes, or 1,048,576 bytes.

If you take the ratio between these numbers and apply it to the 512 megabytes, you get the computer version of the number: 488.281 megabytes. THERE is the great majority of difference in numbers that you see.

[AirEOS]

Thanks guys, i thought it was something like that...cheers guys and girls

[FlyingPete]

The biggest reason for the number difference is this. Hard drive and memory card manufacturers like to advertise the biggest size they can to get you to buy their product. Therefore, they tell you how many megabytes their product has by dividing the total by 1,000,000 (making a "mega" equal one million in their minds). In the computer world, however, a megabyte is NOT a million bytes, but 1,048,576 bytes.

The computer is using a binary counting system. 1 kilobyte is 1024 bytes. A computer megabyte is 1024 x 1024 kilobytes, or 1,048,576 bytes.

If you take the ratio between these numbers and apply it to the 512 megabytes, you get the computer version of the number: 488.281 megabytes. THERE is the great majority of difference in numbers that you see.

Around here (at my work) we call that metric megabytes vs imperial megabytes :D