Digital SLR: Digital camera accessories Portable hard-disk drive
If you're shooting really intensively with your digital camera, for example on a long cruise or safari, and feel you could fill your memory card many times over before you can get to a computer to transfer your images, a portable hard-disk drive could be handy, though they are quite expensive, starting from over £100.
The smallest portable hard disks are around 40GB in size, giving approximately 20 times the memory space of a 2GB memory card.
However, as memory card prices fall, large hard drives become primarily useful as backup devices.
To transfer your pictures and video from memory card to the portable hard-disk drive, you can sometimes connect the two using your USB cable, or some devices have a memory card reader in them, which is a far quicker process.
Some portable hard disks also have an LCD viewing screen, allowing you to view images and movies.
Screens vary between about 2.5-inch and 7-inch, and the larger screens with higher resolutions (eg 800x480 pixels) provide a clearer way to review your photos than on your camera's LCD screen, while also saving your digital camera's precious battery.
If you have an Apple iPod or other MP3 player with a photo viewer, this can also be used to store and view your photos on the move.
| Number of Jpeg photos which fit on a 1GB capacity memory carda | |||||||
|---|---|---|---|---|---|---|---|
| Image resolution | 2Mp | 3Mp | 4Mp | 5Mp | 6Mp | 7Mp | 8Mp |
| Jpeg photos | 1140 | 850 | 510 | 410 | 320 | 260 | 230 |
Table notes
- Based on average file sizes. Actual number of images per card will vary and depends on the camera model and type of scene being photographed
Looking to buy a new digital camera? Read the Which? guide to choosing and buying a digital camera.
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