Digital Film – Flash Memory Storage for Digital Devices
Flash memory has changed the face of removable and portable storage for digital devices. There are dozens of flash memory formats on the market, which are considerably smaller, have faster read/write times, and store more data than their predecessors of yesterday. In fact, you can store more data on a flash drive that fits onto your key ring than a small mountain of floppy disks from just a few years ago.
Flash memory is a lot like your home computer’s memory in that it is often used to hold control code such as basic input/output system (BIOS) information. But, flash memory has the ability to act like a hard drive in terms of being able to store data-large amounts of data. And unlike your hard drive, flash memory is non-volatile. This means no power is required to maintain the information stored in the chip.
Other reasons why flash is so universally accepted are its durability and kinetic shock resistance, ability to withstand extremes of temperature, and even immersion in water.
HISTORY
The initial steps of the digital age to bring the PC into the American home were usually not much more than a keyboard, a mouse, a monitor, and maybe a dot matrix printer. It wasn’t long before users wanted to transfer information from one computer to the next or simply share their data between family and colleagues.
The industry tried many forms of magnetic storage mediums to satisfy the needs of consumers and businesses alike. For short periods of time they all performed well: 1.44MB diskettes, SuperDisks, Zip disks, magnetic tape, and more. All these mediums eventually failed and were replaced by flash technology because of three key reasons:
- Magnetic media is susceptible to accidental erasure: degaussing by exposure to magnets, AC-powered equipment, heavy power lines, and power transformers. Magnetic media is also quite vulnerable to environmental degradation.
- Both the storage medium itself and the device consist of many mechanical parts and users risk the chance of having a device malfunction, making it impossible to read or write to the storage medium, resulting in permanent data loss.
- Compatibility issues such as storing files on a Zip disk meant the next user needed access to a Zip drive to read or transfer the files.
FLASH CARD TYPES
Which type of flash memory card you’ll need depends on the type of device you have. Some devices can accept more than one type of flash memory card. For example, the Sony 10.2MP Digital SLR (Model No: DSLRA300K) accepts the CompactFlash Type I/II cards and the Memory Stick Duo Pro card. When purchasing a device that stores files on flash memory, ensure you have the correct storage medium.
By far the most popular flash memory card for digital cameras is the Secure Digital (SD) card. The SD card is nearly identical in size to the MultiMedia Card (MMC) but technically very different on the inside. Not all cameras that use SD cards can also use MMC cards, so check your camera’s user manual.
The following chart shows a few of the more common types of flash memory cards and gives usage examples for each card:
STORAGE CAPABILITIES
The number of photos, songs (minutes), and other data that can be stored on a particular flash memory card will depend on the file’s format resolution and compression, and the device model itself. Plus, the actual usable memory capacity may vary by each card.
The following chart compares how many images (2MP to 12MP) can fit onto an individual flash memory card (128MB to 4GB):
The following chart shows how many four minute songs in MP3 format can be stored on an individual flash memory card (128MB to 4GB):
The following chart shows how many minutes of video in MPEG4 format can be stored on an individual flash memory card (128MB to 4GB):
SPEED READ RATINGS
With the megapixels rating of digital cameras and other personal electronics going through the roof, the file sizes are getting larger too. This requires more time to write the file to the flash card. Looking for flash media with a higher “X” rating will help store files faster if you have a bad habit of holding down the shutter button on your digital camera.
The “X” rating of flash memory is defined as the minimum sustained write speed from the device to the flash card. For example, Lexar’s 8GB 80X CompactFlash card can record (write) data from the device (e.g., digital camera) at the speed of 12MB per second. How is that calculated?
80 (write speed) x 150,000 (150KB/sec*) = 12,000,000 bytes**
*1KB = 1,000 bytes
150 bytes x 1,000 = 150,000 (150KB/sec)
** 1MB = 1 million bytes
12,000,000 bytes divided by 1,000,000 bytes = 12MB per second of write speed
Some flash memory is rated only by their read speed while others are rated only by their write speed. Typically, read speeds are higher than write speeds so the write speed is more meaningful when measuring performance of the flash card. That’s because most consumers usually care more about how long the data takes to write to the card, not how long it takes to read the data once it is on the card.
X-RAYS & METAL DETECTORS
Some travelers have a concern about whether or not airport X-ray machines and metal detectors (walk-thru and hand-held wand) will damage their flash memory cards or the hardware itself (e.g., digital camera, laptop, etc.). The answer is … no! An X-ray machine does not damage or destroy electronic equipment or its associated media.
The reason for this is because X-ray machines emit electromagnetic energy, which is not magnetic. In fact, X-rays are just light waves of a specific wavelength (like visible light, infrared light, microwaves, and radio waves). Metal detectors used at airports also work on the principles of electromagnetic induction. Since electromagnetic energy is essentially invisible light and flash technology is not sensitive to light, your images, data, and your equipment will not be harmed when exposed to X-ray machines and metal detectors.
FINAL THOUGHTS
When shopping for a digital device, include the type of flash media it uses as one of your considerations. If your printer has flash card slots, ensure the flash card in your new camera will work in your printer. Also, if you’re buying a digital camera and you want to display your work on a digital picture frame, ensure the flash media is compatible with the device.
If your PC doesn’t have flash card slots preinstalled in a drive bay, a card reader might be a great option for you to move files from your digital device onto the hard drive of your computer.
Still have questions?-feel free to speak with an hhgregg associate. We offer the best-educated associates in the business who are smart enough to make it simple. Price and Advice Guaranteed!
