If you’ve read our memory card roundup, you'll know that a number of factors influenced - even limited, the read and write speeds of each memory card. One of these factors was the card reader itself and it was interesting to see how different readers gave different transfer rates when shifting images and/or files to and from the PC – a key step in many digital workflows and one that can truly frustrate the user if it takes a long time.
This workflow bottleneck comes about because many of us go out and buy a memory card and then use it in a card reader without any idea how well they’ll work together. To address this from a manufacturer’s point of view, the obvious answer is to develop both a memory card and reader together so that maximum compatibility, efficiency and data throughput is achieved and sustained.
One company that has taken this approach is SanDisk. It recently launched the new Extreme IV CompactFlash (CF) card along with a new Extreme FireWire reader. When used together (on a FireWire 800-enabled system) the company states that minimum read and write speeds of 40MB/sec can be achieved, although bear in mind that those figures are derived from SanDisk’s internal test data where 1MB equals 1,000,000 bytes.
We on the other hand work to the fact that there are 1,024 bytes in a kilobyte and hence 1,048,576 bytes in a megabyte. Using our calculations, we expect to achieve less than the 40MB/sec quoted by SanDisk, and much less in tests with a Canon EOS-1D MKII and an EOS 5D where we expect to see camera-limited results.
Before we find out how fast the card is, let’s have a look at what you get for your £165. First of all there’s the actual card – in this case a 2GB one (the Extreme IV is also available in capacities of 4 and 8GB). The card design is typical of SanDisk but internally, it’s one of the only CF cards that uses a controller compliant with the UDMA 4 transfer protocol. It also has an extended operating temperature of -25 to 85C.
As for the Extreme FireWire reader, this is a well-made silver unit with a single CF slot, a 9-pin FireWire 800 port at the rear, and a rubber pad on the bottom for added grip. The reader’s controller is compatible with both FireWire 800 and FireWire 400 and also supports UDMA 4. A cable for each FireWire standard is supplied, as is a 30-day trial version of Adobe Photoshop CS2, and a copy of SanDisk’s RescuePRO (Version 3.0) for recovering images and other files that have been deleted.
I’ve tested RescuePro before and have been impressed with its ability to scan any flash card and display a preview of the recoverable data, even after formatting. You can then choose to restore some or all of the recovered images/files to another directory on your PC, or if need be, permanently erase the card.