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Home >> Photography >> Digital The Need for Speed - The Lexar 300X UDMA Compact Flash Card & USB 2.0 UDMA Card Reader
I have five 8 GB CF cards, four from Taiwanese flash card maker, Ridata, and one from US branded, but far east manufactured, Sandisk. I have two 80X Ridata Pro cards and two 150X Ridata Pro cards to go with my Sandisk Extreme III. Thrown into the mix for comparison is a borrowed 4 GB Lexar 300X UDMA CF card, which along with the Sandisk Extreme IV and Ducati models, are amongst the fastest compact flash cards available as of this writing. Some photographers are big into the name brand game and will only buy cards from the big two leading brands of Sandisk and Lexar. However, there are other brands such as Ridata and Transcend to name only two, which are worth a look and for less money than what Sandisk and Lexar charge.
My test is by no means scientific and certainly nothing like the comprehensive tests conducted by noted digital guru, Rob Galbraith with his now famous flash card performance database, but I think it’s representative of what you can expect from the cards. I used my D300 with MB-D10 powered by an EN-EL4 cell to obtain 8 fps performance. I set the D300 on Manual mode with the aperture set to f2.8 and the shutter speed set to 1/250. I shot RAW mode with the D300 set to capture uncompressed RAW files (almost 20 MB per file). My testing procedure was to do a 10 second continuous burst on continuous shooting mode and then counting how many shots I got on the card. After I counted the shots taken I did another 10 second burst and then counted how many seconds it took for the D300’s green writing LED light to go off. After this test, I kept on shooting bursts on each card until I got 100 RAW captures, which would be used to test the upload speed of the Lexar UDMA card reader. I chose 100 RAW files as a nice round figure for comparison purposes. This is approximately 1.85 GB of data from non-compressed RAW files from the D300. Here are the results of the 10 second burst test:
Here are the results of the buffer flushing test (how many seconds to clear the buffer after a 10 second burst):
Conclusion With the Ridata cards, after the buffer fills up, I would have to wait several seconds before being able to take the next shot, whereas the Sandisk Extreme III reduced the wait time to what I subjectively think is about one shot per 1.5 seconds. With the Lexar UDMA card, after the buffer filled, I could take additional shots at about 1 shot per second. If that doesn’t convince you, the buffer flushing speed should as the Lexar blows away my older cards out the window. Part II
The testing is quite simply to copy the files from the CF card to a folder on one of my hard drives. I used copy instead of move, as I needed the files to do a comparison test with two computers. I did try using the move command to move an entire folder of images from the card to the hard drive and this sometimes results in some astonishing time differences, but more on this later below. The results of the upload test are: Lexar UDMA USB 2.0 Card Reader via custom eight core desktop PC computer.
Lexar UDMA USB 2.0 Card Reader via 15.4 inch Sony NR160N Core2Duo notebook computer. I did this test to see what kind of times would be available under field conditions using a notebook computer running on battery power. I did not do full tests with my other Acer 9920 notebook, because this beast is not exactly a field unit; however, tests with the Acer indicate similar times as the Sony.
I did two uploads using my old Lexar USB 2 Multi card reader for comparison purposes. I only did two, because after seeing how slow this old card reader is, I did not feel like waiting to see how long the slower Ridata cards would take to upload the files.
Earlier on I mentioned that I did two tests with the desktop computer. The reason why I did two is because the Firewire 800/USB 2.0 expansion card offered brutally slow times. I started off with the Lexar UDMA card reader connected to the expansion card first and after seeing the brutally slow times, I did the test again with the card reader connected to one of the motherboard’s own USB ports. Both Sandisk and Lexar cards took over three minutes to upload the files, which I knew would not be indicative of the speed potential offered by the Lexar card reader. This shows that not all USB 2.0 ports are equal and that quality matters and counts towards the potential speed available. By the way, the Firewire 800 ports seem quite fast on the card, but more will be said on this in another coming article on the OWC Mercury on the Go Firewire 800 portable hard drive. A curious aspect of my tests is that when I was fooling around with the desktop system, I tried moving the folder of test images to the hard drive instead of copying them. Sometimes, I got some incredible transfer speeds, as in it only took 10-20 seconds (!) to move the 100 RAW files over. And, this was with using the expansion card’s USB port, as well as the motherboard’s USB port and with the Sandisk and Lexar cards. However, other times, I got longer transfer times, but still shorter than copying over the files. Unfortunately, this super speed transfer was not consistent and it was hit and miss as to whether the next attempt would move at the same speed as the copying tests. I could not replicate the speed with either of the Ridata cards and neither notebook computer offered such super speeds either. So, you can give it a shot too if you use a desktop system and see if you might on occasion enjoy supersonic speeds. It seemed to work enough times on my system that from now on, I’ll just move the folder over when using my desktop system. There’s nothing to lose as far as time is concerned, but much to gain. Quite Notes about the Lexar USB 2.0 UDMA Card Reader Conclusion While I don’t have experience with either of the FW800 readers (yet), my recent experience with a FW800 hard drive indicates that FW800 is worth the extra cost over the Lexar USB 2.0 UDMA card reader. No matter which version of the UDMA card reader you choose, there is little doubt in my mind that upgrading to UDMA flash cards is worthwhile if you need to shoot in fast-paced situations where you need to be ready for the next shot as quickly as possible. In fact, I would say that you cannot afford not to. Update July 2, 2008 - Sandisk Extreme IV Compact Flash Card and I received a Sandisk Extreme Firewire 800 card reader and a 4 GB Extreme IV compact flash card the other day, so I did a quick test and compared it to the Lexar UDMA USB 2 card reader and the Lexar 4 GB 300X UDMA card. I ordered these products from Camera Canada, which is a fine online retailer, although I generally do much more purchasing from Vistek. Although I'm not a granola-eating, tree hugging guy in tune with climate change and all that environmental angst, I do have to say I was surprised at the amount of packagaing used by Sandisk. I get a card reader and card coming in boxes that are the same size as what the much larger iPods would come it. I had to hack away at so much packaging for such small products that I was offended and I'm a right wing, red meat eating kind of guy who, despite the high gas prices, would still drive a SUV if his wife would let him own one J Not so much offended, because of environmentalism, but because less packaging should result in cheaper prices ;^) However, after emptying the package I realized why the box is so much bigger than the actual product; Sandisk includes a CD copy of their RescuePRO software with both the flash card and the card reader. Another included CD provides a trial of Photoshop CS2. The card reader also comes with two Firewire cables, one FW800 to FW800 and one FW800 to FW400, which is nice and makes the usual $100 price tag for the reader easier to bear. The $60 Lexar USB card reader came with no cables, which is kinda chintzy given how cheap USB 2 cables must be to make in some Chinese sweat factory. And, to be fair, the Lexar package is even worse than the Sandisk with the horrible, hard to cut bubble plastic. I wonder too, since the flash card is a storage device, why couldn’t the software be saved to it instead with a clear notice on the package that the card has extra goodies installed? For that matter, why not make the software available by download with a provided serial number to unlock the software? Anyway, all this worrying about environmental footprints is making me queasy. I better drive the gas-guzzling minivan the four blocks to Safeway and buy the largest steak I can find for dinner. Then I’ll fire up the bar-be and throw some more carbon into the air to cook the steak for dinner; the bloodier the better. I did the same two tests as I did with the Lexar card and reader a few weeks ago. I timed how many RAW files I could take in a 10 second burst with the Nikon D300 set to manual mode of f2.8 and 1/250 shutter speed. I got 21 photos with the Sandisk card, which is the same as the Lexar card. I then timed how long it would take to flush the buffer after a 10 second burst and here again, the D300 flushed the buffer and wrote all the files to the card in 10 seconds; same as the Lexar card. I then timed how long it would take to download 100 D300 RAW files off the card using the Sandisk Extreme Firewire 800 card reader. The computer used is my cheap Sony notebook with a FW800 ExpressCard adapter. I used this computer, because the heatwave in Vancouver does not make me want to fire up the big desktop and exhaust more heat into the already hot house. Also, the Acer notebook has been acting finicky with the ExpressCard adapter, which might originate in a known problem Vista has with Firewire devices and may require a patch to resolve. Here are the times:
A rough eyeballing of the sustained speed was around 35 MB per second. The Sony notebook did not hit the sustained 40 MB that Firewire 800 should be able to provide with the Sandisk reader, but I suspect the desktop will be pretty close to this as it does provide better times than using the ExpressCard adapter. The speed is better than using the Lexar USB 2 UDMA card reader, but not as dramatically as I had thought with the times being around 15 seconds faster than the USB card reader. However, if we extrapolate to larger cards with more files, those seconds will add up and make the Firewire card reader the go to device to transfer files to the hard drive. I also redid the test using the Lexar USB 2 UDMA card reader and with both the Sandisk and Lexar cards, I hit 1:18 minutes with a rough, sustained speed of around 25 MB per second. This is actually 2 seconds faster than my first round of tests. Objectively, Firewire 800 does provide superior speed over USB 2, but not as dramatically as hoped for. If your USB ports behave nicely and aren’t starving for power then you can get pretty decent speed. For the majority of PC users, the Lexar UDMA USB 2 card reader is the most practical choice, because Firewire 800 is pretty much a foreign interface outside of the Mac community. I was at my local computer shop the other day and asked if they had any FW800 cables and the employee said no, because FW800 is a Mac thing. On the other hand, if you are a Mac user, I’d take advantage of the FW800 interface and get as fast as you can get, which is the Sandisk Extreme Firewire card reader. Card wise, there's nothing really to choose between the Lexar or Sandisk cards. While Sandisk does make a big deal about the Extreme series of cards being hardier than others, there are plenty of pros using the Lexar cards in demanding situations. In choosing between the two big boys of the flash card world, I would simply buy the one that has the best price at the time that a purchase needs to be made. |
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With the Lexar UDMA USB 2 dual-format (compact flash and SD) card reader in hand, I figured I should also do a mini test of some of my compact flash cards and see how fast or, as is likely the case, how slow they are.
While Sandisk and Lexar were first out with Ultra Direct Memory Access (UDMA) cards, there are several other brands that also offer UDMA speed. The thing to note though is whether the other brand cards offer UDMA speed for both read and write. While you may enjoy fast write speeds in-camera, the read speed, i.e. uploading to your hard drive, may be no better than non-UDMA cards. With Sandisk and Lexar, you will get cards that offer UDMA speeds for both read and write and this may explain why these brand cards generally cost more money than other brands.
The second part of this test involved uploading the RAW files taken with the D300 to my desktop’s hard drive via the Lexar UDMA USB 2.0 card reader. I did this test twice, once with the card reader connected to my new Firewire 800/USB2.0 PCI-E expansion card and then again with the card reader connected to a USB port direct to the motherboard. The test results are from the second test, which I’ll explain later on below.
Lexar USB 2.0 Multi Card Reader:
