Olympus Memory Cards allow you to capture much more and in higher resolution before the images
must be downloaded or the card changed. Compact and durable, the Olympus xD-Picture Card is the ultimate reusable digital media. Besides offering compatibility with most manufacturers xD-compatible devices, it's the only xD card that supports the Panorama function found on most Olympus digital cameras. And it's just as easy using non-xD devices as well, thanks to a number of groundbreaking adapters that will be available including a CompactFlash Adapter, SmartMedia USB Reader/Writer, and PCMCIA/PC Card Adapter.
Shop for Olympus Memory at these stores
||Olympus M+ 2 GB xD-Picture Card Flash Memory Card 202332: $13.88
||Olympus M+ 1 GB xD-PictureCard Flash Memory Card 202331: $14.99
IDE (ATA) emulation speed is usually specified in "x" ratings, e.g. 8x, 20x, 133x. This is the same system used for CD-ROMs and indicates the maximum transfer rate in the form of multiplier of the data rate of an audio CD, which is 150 KB/s.
where R = transfer rate, K = speed rating. For example, 20x rating means 20 * 150 KB/s = 3,000 KB/s = 3 MB/s.
These are manufacturer speed ratings and actual transfer speed may be higher or sometimes lower that one shown on a card
There are different speeds of SD card available. The official unit of measurement is the Speed Class Rating; an older unit of measurement is the × rating.
Speed Class Rating
The Speed Class Rating is the official unit of speed measurement for SD Cards, defined by the SD Association. It is equal to 8 Mbit/s, and it measures the minimum write speeds based on "the best fragmented state where no memory unit is occupied
The following are the ratings of some currently available cards:
Even though the class ratings are defined by a governing body, like × speed ratings, class speed ratings are quoted by the manufacturers but unverified by any independent evaluation process.
- Class 2: 16 Mbit/s (2 MB/s)
- Class 4: 32 Mbit/s (4 MB/s)
- Class 6: 48 Mbit/s (6 MB/s)
- Class 10: 80 Mbit/s (10 MB/s)
Important differences between the Speed Class and the traditional CD-ROM drive speed measurement ("×" speed ratings) are:
On 21 May 2009, Panasonic announced new class 10 SDHC cards, claiming that this new class is "part of SD Card Specification Ver.3.0". Toshiba also announced cards based on the new 3.0 spec As of December 2009, the SD Association's Web site does not include information on this new class or new specification.
- 1. the ability of the host device to query the SD card for the speed class and determine the best location to store data that meets the performance required
- 2. class speed defines the minimum transfer speed.
Since the class rating is readable by devices, they can issue a warning to the user if the inserted card's reported rating falls below the application's minimum requirement.
The × rating is a unit of measurement equal to 1.2 Mbit/s. It is derived from the standard CD-ROM drive speed of 1.2 Mbit/s. Basic cards transfer data up to six times (6×) the data rate of the standard CD-ROM speed (7.2 Mbit/s vs 1.2 Mbit/s). The 2.0 specification defines speeds up to 200×, but unlike the class rating system, does not mandate that x-ratings measure the card's sustained write-speed. For most cards, the maximum read speed is typical faster than its maximum write speed, leading some manufacturers to use read-speed as the ×-rating measurement. Other vendors, such as (Kingston, use write-speed.[
This table lists common ratings and minimum transfer rates.