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 Table of Contents Beware of unannounced changes to product specifications Don’t miss MacPerformanceGuide.com — read about the latest on how to select and configure a Mac, optimizing Photoshop, hard drive performance, RAID, and more! NOTE: In mid-July 2006, SanDisk announced their Extreme IV cards and their outrageously fast Firewire card reader to exploit the IV-series cards. This article will be updated when those items become readily available. See also Beware Transferring files from a digital camera to a computer is a frequent task. With today’s 4GB, 8GB and soon-to-arrive 16GB cards, digital camera users who regularly shoot a gigabyte or more of images need a solution that offers high performance transfer speeds (10 megabytes per second or faster). Even so, a full 8GB card would take 6-7 minutes to transfer—too long for some applications such as downloading 100 cards from a day’s shooting at the SuperBowl (multiple photographers). This article examines 3 of the 4 common methods for transferring files from Compact Flash and Secure Digital (SD) cards to a computer. These include:
Invariably the 480Mb/sec of USB 2.0 is slower than 400Mb/sec Firewire 400 (“Mb” = megabits, 8 bits per byte). The 80Mb/sec theoretical advantage of USB 2.0 over Firewire 400 in reality translates to an inferior real-world performance of 40% to 80% the speed of the “slower” Firewire 400; real-world performance is typically 130Mb/sec or so. I used a PowerMac G5 Quad for most tests. Speed was tested three (3) ways:
Please note that memory card capacity and speeds quoted by SanDisk, Lexar et al define megabyte as 1,000,000 bytes whereas DiskTester and other timing results use the more common computer value of 2^20 or 1,048,576 bytes. Thus, a 4GB card is a 3.814GB card, a quoted 10MB/sec is 9.54MB/sec, and 20MB/sec is 19.2MB/sec. The crops below from both MacOS X and Windows XP demonstrate that they both agree that a 4GB SanDisk card is 3.8GB where GB (gigabyte) = 1024 X megabytes.
Drive manufacturers would rather advertise a 4GB card than a 3.8GB card, a choice that only serves to confuse customers in light of the approach taken in both Windows XP and MacOS X. Many users will simply wonder why their card is always smaller than it should be. No doubt there have been more than a few technical support calls for this simple reason. There must be at least a few lawyers out there mulling this over.
All tests were done on a PowerMac G5 Quad using MacOS X unless otherwise noted. A few were done on the MacBook Pro [see MacBook Pro Experience Report], using both MacOS X and Windows XP SP2. Not all possible combinations were tested because the fastest card speed in the fastest reader is what most readers will care about. The slower cards and slower readers serve to illustrate differences; there is little point in ranking inferior alternatives when the cost of the fastest reader tested (the Lexar RW019-001) is only about $42. I tried direct connection of both a Canon EOS 1Ds Mark II (USB and Firewire) and a Canon EOS 5D (USB), but no drive icon would appear on the desktop. By comparison, the Nikon D2X worked flawlessly when directly connected. The two Lexar cards showed that 80X vs 40X might be only marginally faster, a surprising
result. However, the particular 4GB card tested had been replaced by Lexar for firmware issues, so although
labeled “40X”, perhaps it was silently replaced with 80X innards, with no change in exterior appearance
eg a “silent upgrade”.
(1) There are no readily available Firewire card readers for Secure Digital (SD) cards, which is a shame, since SD cards can be quite speedy—and they are not just for use with consumer digicams; the Canon EOS 1Ds Mark II offers a Secure Digital card slot in addition to its Compact Flash slot. There does seem to be at least one obscure brand available, the Amtron IEEE 1394 FireWire 2-Slot 6-in-1 Flash Card Reader/Writer). There are also a few readers intended for installation in a 5.25" bay in a desktop PC. There are also adapters available [Amtron, PSI]which allow insertion of a Secure Digital card into a Compact Flash form factor. I have not tried these products, and they are relatively expensive. All tests were done on a PowerMac G5 Quad using MacOS X unless otherwise noted. Given the quite good performance of the Lexar Single Slot Multi-Card Reader, it is a screaming deal at $15.99 (at the time of writing this article).
(1) SD2-UII = SanDisk 2GB Ultra II The Delkin web site makes this claim about their DDReader-24: “The Reader-24 allows lightning-fast FireWire transfers to and from your CF card and computer” (emphasis added). This claim is dubious, given the unit’s bottom-of-the-barrel performance. Here’s what Delkin has to say about it (May 15, 2006, email reply from sales): The transfer speeds will vary, based on too many options, making it pretty much impossible to determine what kind of speed you will see. If referring to one of our Pro Cards the max speed is 16.5 MB (110X) and the standards are 8.25 MB. However if you have programs running at the same time it will vary. The size of each file and the specifics of your computer will also determine the speed. Other then a cardbus adapter the fire wire reader will offer you the fastest speed possible. I hope this helps and please let me know if you need anything else. So apparently it’s fine to claim “lightning fast” in marketing materials, even though it’s “pretty much impossible to determine”. As a 20-year software engineer, having written a number of benchmarking programs, I beg to differ. While it’s absolutely true there can be variation, I have seen almost no variation in my results testing the cards and readers described in this article (for any given machine/card/reader). Even across machines, the results are close enough to make accurate claims quite possible. SanDisk’s web site claims the following about their ImageMate® 12-in-1 Reader/Writer (not tested): “USB 2.0 provides superior performance to transfer pictures...”. Superior to what? Such unsubstantiated claims demonstrate the time-honored caveat emptor principle—and my hope is that this article will help the reader obtain the most appropriate card reader for their needs. Beware of unannounced changes to product specifications On September 10, 2006, a reader emailed me, reporting having purchasing a SanDisk Extreme FireWire CompactFlash Card Reader from B&H Photo Video (one of the stores I regularly use with nary a problem), but not receiving any “hard case” as claimed in the product description (see below, click for larger version).  According to the reader who emailed me, when contacted, neither B&H [1, 2] nor SanDisk were able to supply the hard case (though the reader states that B&H “did apologize and I didn't ask for anything more”. While mistakes can be made in describing products, advertising one thing and supplying it without claimed items is fraud when done deliberately (no evidence of that here)—but at the very least a company ought to go the extra mile to make up for the mistake. For this particular item, a “hard case” is a not a “de minimus” item, but rather a useful item for transporting and protecting the unit, some buyers might be disappointed. SanDisk has two conflicting links on their site as of September 10, 2006 (links might change subsequent to this posting; the first link below includes the hard case): SanDisk
Extreme FireWire Reader The change in specifications is rather interesting. Whether this is a marketing mistake or a real change in the product performance is unclear. The revised specifications omit:
Has the quality of the product declined? If so, this is an interesting variant of the usually not-so-subtle “bait and switch” tactic. Perhaps nothing has changed, or perhaps SanDisk has found a way to increase their product margins—by omitting the shock and water resistance and temperature testing. It does seem odd that such features, which are significant selling points, would now not be considered important to marketing the product, so I’m inclined to think that SanDisk has chosen to increase their margins, with no disclosure of the change in product performance relative to the original press release. Perhaps SanDisk will clarify their position. The reader who emailed states: “Now about B&H Photo. I have purchased from them for years and have always been very
well satisfied, both Adobe software and digital camera hardware. Never a problem. The reader’s reason for buying the SanDisk reader was an overheating Lexar RW019-001 FW400 Reader (with multiple cards). This might not be a unique problem; see Lexar JumpDrive FireFly and JumpDrive 1GB Secure II Product Recall. Compact Flash For professional use involving Compact Flash cards, a fast Firewire card
reader such as the Lexar RW019-001 Firewire card reader [buy The SanDisk ImageMate 12-in-1 is also a good choice, with the benefit of supporting virtually all types of cards, but is about 25 % slower than the Lexar RW019-001. Secure Digital (SD) Either card reader offers read performance vastly better than connecting the camera to the computer, though it seems likely that there might be other cameras with usable performance when directly connected. It would be interesting to test SanDisk Extreme III SD cards in these units (with claimed speed twice that of the Ultra II line). The SanDisk
ImageMate 12-in-1 [buy The Lexar Single Slot Multi-Card
Reader [buy Direct Connection Direct connection of a camera to the computer using USB 2.0 offers speeds ranging from unusable to poor. It is simply not an option except for casual use, or users who have very little data to transfer. Only a single Windows XP test was done. Performance was quite good, though slower than that on MacOS X (using the same card and reader). See also robgalbraith.com: SanDisk ImageMate readers jump to the head of USB 2.0 class SanDisk poised to unveil Extreme IV CompactFlash and Extreme Readers Contact: email diglloyd a comment on this article.
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Delkin512
LEX4-40XWA
LEX4-80XWA
LEX2-80XWA
]
(about $43) is the best option for Compact Flash cards. I haven’t yet tested the 
