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Review: Kanguru Media X-Change 2.0
Portable card-reader hard drive for digital photographers.
In my quest for the perfect set of digital photography gear for those who travel, I have spent considerable time thinking about what gear might address our special needs. Besides losing all photos, it is clear that one of the worst situations a digital photographer might face on the road is one that prevents him or her from shooting. Battery life, storage and redundancy are the important issues to solve. The adventurous digital photographer who spends significant time in remote regions, away from electricity, faces a difficult situation: what to do once the memory cards are full?
Kanguru has two products in their line-up which help address this issue: a portable card-reading hard drive (Kanguru Media X-Change 2.0) and a portable card-reading CD-ROM burner (Kanguru Slim FC-RW). This review will focus on the first of these, the portable hard drive.
Kanguru Media X-Change 2.0
The Media X-Change 2.0 is the latest verison of Kanguru's portable hard drive solutions (personal digital storage device) with integrated flash memory card readers. The product is designed to be a compact storage for digital photos when away from a computer. A digital photographer would then no longer be limited to the capacity of the memory cards, and instead have the ability to shoot the equivalent of 20-80 1GB cards.
|List price||20GB - U2-KMX-20 - U$199.95 (as listed on Vendor's site on Mar 2005)
40GB - U2-KMX-40 - U$229.95
60GB - U2-KMX-60 - U$279.95
80GB - U2-KMX-80 - U$329.95
|Dimensions||5" x 3" x 1"|
|Weight||1/2 lb (288 g)|
|Display||2" black & white LCD (non graphical)|
|Card compatibility||Compact Flash / Microdrive (CF I/II), Smart Media (SM), Secure Digital (SD), Multimedia Card (MMC) , Sony Memory Stick (MS)|
|Operating System||PC & Mac|
|Computer Interface||USB 2.0|
The overall unit is attractively styled with a modern grey and silver two-toned curved look. Encased in hard plastic, the device feels rugged and probably could withstand some moderate abuse in a camera bag.
The interface is extremely simple, providing two slightly-recessed buttons: Power and Copy. It would be very difficult for these buttons to be accidentally pressed in your camera bag. Even still, the device would automatically power-off after a minute of inactivity. In case of a device lockup, there is also a hard reset button which could be triggered with a paperclip or pin.
The display is a standard LCD display with a number of fixed icons (ie. not dot-matrix or graphical). It is easy to read and it is intended to simply summarize the operational state of the device. Other devices on the market can display full-color previews, but this generally comes at a high cost, and is of questionable use.
The DC power input and mini USB connector can be found on one side of the device. A protective rubber flap covers the USB port and helps prevent dust and dirt from getting into the connector.
Focus of Testing
For the purposes of this test, I have focused primarily on the uses I see for a digital photographer, even though this device could certainly be used for other storage needs. Given the limitations of my test environment, I am only testing the following configurations:
- PC (Athlon XP 2.5GHz), no testing on Macintosh
- Compact Flash type II only (no other card reader formats). My testing is done with three different speeds of memory cards, ranging from the original Sandisk memory card through to the fastest Sandisk Extreme card.
- 20GB version of the device (the configuration as provided as a sample for my review)
For products in this category, speed is an important issue. The main reasons being:
- Time to copy card to internal drive - Not only does this time eat up the internal battery life (thus preventing more copies), but it also potentially locks one out of using the same card for a period of time. Having multiple memory cards removes the second concern. The first issue is still remains the most critical.
- Time to copy internal drive to PC - Even with a USB 2.0 connection, most products rarely transmit data at anywhere near the 60 MB/sec that is physically possible. At the end of a shoot, one needs to recover the photos onto a host computer and reducing the amount of time transfering data at this stage is a nice convenience.
The following tests will evaluate how the Kanguru Media X-Change 2.0 performs in the way of throughput or speed.
The Kanguru Media-Xchange (KMX) was connected to the PC via the supplied cable to a USB 2.0 port on the computer. This USB2 port was integrated on the motherboard and did not pass through a USB bridge card (which could affect performance).
The memory cards were preloaded to maximum with RAW digital photos (eg. Canon .CRW files, approximately 5.5MB each) with no thumbnails (eg. Canon .THM files, approximately 10KB each). The reason for the removal of the thumbnails is to test maximum performance on the large files without incurring the overhead associated with the copy over of small thumbnail files. Many digital cameras do not create these additional thumbnail files, and so by omitting them one can derive the most representative performance for all camera models.
For each test, the memory card was inserted into the KMX unit, powered on and then immediately (after the internal drive had spun up, roughly one second later) the COPY button was pressed. The timing was started from the time that the COPY button was pressed until the audible beep at the completion of the transfer was heard. Throughput data (transfer rates) were measured by dividing the total file size (on disk in bytes) by the transfer time in seconds. Note that the units of KB and MB are the true units (ie. 1024 bytes to a KB, 1024 KB to a MB).
The last set of results (with the KMX internal drive only) were extracted from the SiSoftware Sandra benchmarks.
In all cases, the memory cards were transfered with their full capacity (within the granularity of a single RAW digital photo file +/- ~6 MB). For the 1 GB tests, the actual data size (on disk) is 1,021,575,168 bytes or 974 megabytes. For the 512 MB tests, the actual data size (on disk) is 508,887,040 bytes or 483 megabytes.
|Card Transfer: Write Speed
Memory Card to KMX Internal Drive
|Sandisk 1GB Extreme > KMX||1023 KB/sec||[16:15 for 974 MB]|
|Lexar 512MB 40x > KMX||1001 KB/sec||[8:15 for 483 MB]|
|Sandisk 1GB Original > KMX||970 KB/sec||[17:09 for 974 MB]|
|Card Transfer: Read Speed
KMX Internal Drive to PC via USB 2.0
|KMX > PC||4072 KB/sec||[4:05 for 974 MB]|
|Drive Transfer: Write Speed
PC to KMX Internal Drive via USB 2.0
|PC > KMX||4209 KB/sec||[3:57 for 974 MB]|
KMX Internal Drive only
|Sequential Read||4 MB/sec|
|Sequential Write||5 MB/sec|
|Avg Access Time||9 ms|
From the above results, one sees that the speed of the memory card has only a minimal effect on the transfer speed (from flash memory card to the Kanguru Media X-Change internal hard drive). The performance bottleneck is most likely in the flash memory controller, not in the drive itself.
The overall transfer times are roughly:
- 16 minutes to transfer 1 GB of data from a card to the KMX drive
- 8 minutes to transfer 512 MB of data from a card to the KMX drive
- With smaller files, one would expect slightly slower transfer rates as the overhead from each file transaction will be a larger fraction of the total time.
|Card Reader: Read Speed
Memory Card to PC via USB 2.0
|Sandisk 1GB Extreme > PC||4555 KB/sec||[3:39 for 974 MB]|
|Lexar 512MB 40x > PC||3976 KB/sec||[2:05 for 483 MB]|
|Sandisk 1GB Original > PC||2347 KB/sec||[7:05 for 974 MB]|
|Card Reader: Write Speed
PC to Memory Card via USB 2.0
|Sandisk 1GB Extreme < PC||NOTE 1|
|Lexar 512MB 40x < PC||3030 KB/sec||[2:44 for 483 MB]|
|Sandisk 1GB Original < PC||1189 KB/sec||[13:59 for 974 MB]|
NOTE 1: It seems that the Kanguru Media X-Change had some trouble writing to the Sandisk 1GB Extreme card directly from the PC over USB 2.0. Immediately after trying to initiate the transfer, the drive activity would cease and a timeout error message was reported, "Path too deep". No files were ever transferred. [03/10/05]: According to Kanguru, a firmware update will be released soon to correct this compatibility issue.
Used as a card reader (ie. bypassing the internal drive), the Kanguru Media X-Change offered satisfactory throughput rates, a little under half the speed of a dedicated USB 2.0 card reader. It is good to see that the device can be used in this manner, reducing the need for yet another USB peripheral.
Performance: Battery Life & Endurance
Given that an expected use of this product is one in which the user is on the road, battery life is of the utmost importance (more important than speed, although it is obviously interrelated). This is even more of an issue if the digital photographer is in a remote region well away from electricity.
As the Kanguru Media X-Change 2.0 does not have a user-serviceable / replaceable battery pack, one is quite dependent upon the performance of the built-in battery pack. The following tests attempt to evaluate how much life and data can be transferred before the unit runs down.
For devices in this category, a key measure of performance is how many gigabytes of data can be transferred from card to internal drive on a single charge? Some authors call this figure the degree of "autonomy". As different memory cards have different maximum transfer rates, it is likely that this figure is dependent upon the type of memory card used.
Trying to replicate the sort of scenario one would encounter on the road, the testing follows the simple pattern shown below. All tests were performed after a full charge (4-8 hours, more than the 3 hours prescribed in the manual). The cycle was repeated until the batteries were exhausted.
- Place full memory card into slot
- POWER on the KMX device
- Press COPY
- Once the COPY is complete, press the POWER button.
The following results indicate the total amount of data transferred before the device ran out of power from the internal battery.
|Memory Card||Transfers||Total Data Transferred||Total Time|
|Sandisk 1 GB Extreme||4.4||4 x 975 + 391 = 4291 MB||1 hr, 11 minutes|
|Lexar 512 MB 40x||8.4||8 x 484 + 235 = 4107 MB||1 hr, 10 minutes|
- Overall battery life: Approximately 1 hr, 10 minutes (1.2 hrs) of active use, or just over 4 GB of data
This result matches the rating indicated on Kanguru's web page which states a lifetime of 1.2 hours continuous operation.
What happens when power runs out?
It is guaranteed that one will run out of power at some point during a transfer while using a device like this. In such a circumstance it is important to consider what this will mean to your workflow. With the Kanguru Media X-Change 2.0, the device simply shuts off during the transfer, without any final warning beep. When one recharges the batteries enough to turn the unit back on, there is no indication of the failed previous transfer (this is a feature that I would like to see). So, it is conceivable that one could possibly miss a failed transfer and assume that the device must have auto powered-off. If one then simply recharged the unit, it would be difficult to recognize the failed transfer.
The files that transferred up until the power-down are fine, but the last file touched will be corrupt, as expected. In such a situation, the user will need to redo the entire transfer again as there is no way of telling how much has been transferred or instructing the device to copy only part of a card. For space and power reasons, one should probably avoid causing these failed transfers.
The unit couldn't be any easier to use — just insert your memory card, press the power button and the copy button. After a few minutes, an audible beep indicates that the transfer is done, and the card can be removed. After formatting the card in the camera, it's time to shoot the next "roll". Each transfer creates a new folder on the drive, enumerated from 0000 to 9999.
Although there is no hard drive delete function from the unit itself (without connecting it to a PC and performing the delete there), this is probably a good safeguard. I am sure that in the presence of such an option, at least one unfortunate photographer would end up triggering it accidentally.
With all devices targeting this market, one might feel slightly uneasy about copying the photos and then wiping them out, while trusting that the copy was successful. If it were to include a mode to verify the transfer or display the number of images that were copied, one might feel a little more at ease. That being said, I have yet to encounter an erred copy operation from such a device.
The package also includes a nice carrying case that fits the unit along with four memory cards and a mesh pocket. While the case does offer some additional protection, it's main purpose should to keep everything together and protect it from scratches and the elements. Even though I could fit the mini-USB cable inside the case, it would not accommodate either power adapter, which would be necessary for longer trips.
Another nice accessory included in the package is the car charger. For distant travels (eg. living out of a Land Rover in Africa), this might be the only means of recharging the device, and so it certainly adds value.
Even though the product performed its function very well, there are a few features that would be nice to see in future revisions of the product:
- Increased battery life, or an option to allow the user to replace the battery with a second one (to extend one's range).
- Countdown display for transfer progress.
- Increased card reader throughput (from card to internal hard drive).
- Indicator on display that last transfer failed.
- User-replaceable internal drive, or an option to purchase just the drive enclosure.
[03/10/05]: According to Kanguru, a third generation device (flash card to hard drive solution) will be released soon, which apparently addresses many of these issues.
The Kanguru Media X-Change 2.0 is a robust portable storage device that would work well for digital photographers who need the ability to shoot a large number of shots away from their PC. For those traveling to remote countries where electricity is hard to come by, or simply out on location for a long period of time, the extended storage capacity has its obvious advantages. Although there is room for improvement in the battery life and card-to-drive throughput, most users will probably find the extended capacity to be more than sufficient for their needs.
The display is easy to read, and the device was incredibly simple to use. Windows XP SP2 detected the unit without any troubles and mounted four drives (three for the various supported card types, and one for the internal drive). My automated photo importing software didn't have any troubles pulling the photos into my workflow from the internal drive. For those digital photographers looking to extend their range, the Kanguru Media X-Change 2.0 certainly offers a decent solution.