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Digital Camera Storage Media

Digital Camera Media Guide

Digital Camera Memory Cards

The digital equivalent of film, removable memory cards are what digital cameras use to store the images they have taken. The size of commonly-used memory cards is measured in megabytes (MB) or gigabytes (GB), and depending on the size of the card and the format of the images saved on it, a card can hold anywhere from one to many hundreds or even thousands of digital images. When a memory card is full, the camera owner can either delete images from the card or transfer them to a computer or storage device to free up space for additional pictures.

There is a dizzying array of memory cards in different shapes, sizes, prices, and brand names. The make of your digital camera dictates which type of card you buy.

Back in the early days of digital cameras, you could choose CompactFlash, SmartMedia, or the Memory Stick. Today SanDisk, Lexar, and a throng of lesser-known names manufacture CompactFlash and MultiMedia Cards. The tiny xD Picture Card is replacing a dying SmartMedia card.

Capacity

The vast majority of digital cameras come standard with memory cards (often 8, 16, 32, 64 or 128MB) that are too small for the active photographer. Cameras are capable of saving images in a variety of formats and resolutions. Owners should purchase additional memory cards that can store at least 40 images or more in the highest quality Joint Photographic Experts Group (JPEG) format, the most commonly used image file type.

Advanced photographers intent on shooting and editing the highest quality images possible should purchase higher-capacity memory cards to accommodate the much larger uncompressed RAW and TIFF image files.

Formats

There are several memory card formats available, including CompactFlash, Secure Digital, Memory Stick, SmartMedia, MultiMedia Card (MMC), and xD Picture Card. With the exception of the few cameras that can accommodate two types of storage device, digital cameras require a specific memory card format and are not compatible with any other type of memory card.

The different formats offer comparable image quality, though they vary in speed and available memory. CompactFlash is currently the most popular among camera manufacturers and is also available in the largest size - up to 2 gigabytes! With the advent of xD cards by Fuji and Olympus, it appears that SmartMedia format may be on the decline, but keep in mind that it is hard to make the wrong choice of formats, unless one plans to swap the memory card from a digital camera to a future device like a digital video camera or a digital music player.

Speeds

Some memory card manufacturers, including SanDisk, Lexar and SimpleTech, are releasing new models with higher speeds. These cards are more expensive, but for some photographers they're worth the price, because it takes less time for the image to be sent to the card - and so shot-to-shot time can be reduced. While the casual photographer may not notice the difference, this speed is crucial for photographers who take live-action shots in continuous mode - like at a sporting event, for instance.

Manufacturers/Brands

Memory cards are produced by a number of different companies, including the camera manufacturers themselves. Price is dictated by the brand and speed of the card, but don't feel obliged to buy the most expensive card, as long as the format is correct and the card has a one-year warranty.

High speed memory cards that record data more quickly and allow faster shot-to-shot times are available at some retailers - if speed is a concern, and you can spare the extra money, look for Lexar high speed cards, SimpleTech ProX cards, or SanDisk Ultra cards, which offer substantially faster speed than standard memory cards.

The price of memory is falling by the day, however, and should continue to do so, making even large-capacity cards available to the budget-conscious consumer.

Memory Card Reader

A related accessory that digital camera owners find to be very useful is a memory card reader. Memory card readers, some of which are available for less than $30, plug into your computer and let you transfer images from a card without connecting your camera to the computer. This allows for much faster image download times and simpler operation. Owners of laptop computers can even buy a card reader that will slide directly into their PC card slot.

SONY Digital Camera Media:

Compact Disc Media > CD-R & CD-RW Optical Drives

Sony CD-Mavica digital camera media: CD-r and CD-rw

Sony often goes their own way and digital cameras are no exception as Sony offers their CD-MAVICA digital cameras based on the mini-CD media to store images instead of memory cards (although Sony also offers many, if not most, digital cameras which use their memory stick media).

Sony digital CD-MAVICA cameras can store images on CD-R or CD-RW discs. The discs themselves are made of inexpensive polycarbonate plastic and cost less than 70 cents each for mini CD-R discs. Discs are available in retail stores and online. Data is stored in the form of microscopic pits burned into the top surface of the disc by a laser. The data is arranged in a continuous spiral with concentric tracks. The surface of the disc is then coated with an ultra thin layer of reflective material which makes the surface shiny.

Inside the drive is a laser which is focused with a lens. The laser is located underneath the disc, and the light passes through the bottom of the disc then bounces off the reflective surface. When the laser hits a flat spot or "land" the light reflects back to a light-sensing detector. But if the laser beam hits a "pit", the light is scattered and not picked up by the detector.

CD-R
We're all familiar with audio CDs and CD-ROMs (Read Only Memory) which store data, but you can't record on them. To write to CDs you need a CD-R (Recordable) or CD-RW (Rewritable) drive. CD-R is sometimes referred to as CD-WORM for "write once read many" which means you can burn information onto CD-R discs only once. They are not re-recordable so they are suited for long-term archiving or making audio mix CDs.

A CD-R blank is made much like a regular CD except it has a layer of photosensitive dye on the surface covered by a reflective layer of gold or silver alloy. The dye layer and metallic alloys give CD-R discs their distinctive physical appearance. CD-R drives contain a specific type of laser which heats the photosensitive compounds in the dye, chemically altering them. When the laser burns the dye it becomes less reflective and acts like a traditional "pit".

Many CD-R drives let you write to the disc during more than one sitting. This multi-session recording lets you add data to the CD later if the disc isn't full. The CD-R discs you burn can hold up to 650 MB and can be read by most CD players and CD-ROM drives, though not all players can read multi-session recordings. The low cost of CD-R blanks makes them popular for sharing files and audio mix CDs since CD-R drives play both audio CDs and CD-ROMs.

CD-R drives always read much faster than they can write. For example, a drive that has specs of 8X/2X will read four times faster than it can write. Each multiple unit of "X" means the drive can read/write at 150 KB/s. Current CD-R models read at 8X-32X and write at 2X-8X. It can take anywhere from 9 to 40 minutes to burn an average 74 minute blank CD.

CD-RW
To move beyond the write once limitation, you'll want a CD-RW drive which allows you to record information over previous data. A CD-RW disc is constructed similarly to a CD-R disc except the dye layer is replaced by a special phase-change compound. This substance changes state when it absorbs a lot of energy, going from an ordered crystalline state to an amorphous (non-crystalline) state. If slightly less energy is applied, the amorphous state can be changed back to the crystalline form. On the disc, crystalline areas reflect light like a "land" and amorphous areas absorb light like a "pit."

The drive's laser is capable of three power settings. The highest is the "write power", the middle power is the "erase power" which changes the compound back to its crystal form, and the lowest "read power" doesn't cause a phase change. CD-RW discs can be rewritten around a thousand times, and they are multi-session discs.

CD-RW discs reflect less light than a standard CD which makes them incompatible with audio CD players and older CD-ROM drives. However, you can always burn CD-R discs in a CD-RW drive if compatibility might be a problem. CD-R blanks are also much cheaper than rewritable discs. A CD-RW drive can also read all forms of CD media. Any CD or DVD player with the "MultiRead" specification will read CD-RW, CD-R and CD-ROM discs.

CD-RW drives read faster than they write and write faster than they rewrite. Depending on the model, they can read at 6X-32X, write at 2X-12X and rewrite at 2-10X. The standard notation order is write/rewrite/read. A CD-RW blank is rated for a certain write speed which is the upper limit, even if your drive can write faster than the rated speed.

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