Posts Tagged ‘Digital Cameras’

Card Reader

Friday, December 12th, 2008

“Card reader” is the generic term for an input device that reads flash memory cards. It can be a standalone device that connects to a computer via USB or it may be integrated into a computer, printer, or multifunction device. In fact, most multifunction printer/scanner/copiers now have built-in card readers.

Most card readers accept multiple memory card formats, including compact flash (CF), secure digital (SD), and Sony’s Memory Stick. Some card readers accept various other formats such as XD, SmartMedia, Microdrive, and Memory Stick Pro Duo cards.

The purpose of a card reader is, not surprisingly, to read the data from a memory card. When you place a memory card into a card reader, it will often show up on your computer as a mounted disk. You can then view the contents of the memory card by double-clicking the card’s icon. This icon typically appears on the desktop of Macintosh computers or inside “My Computer” on Windows machines.

Since memory cards most often contain pictures from digital cameras, a photo organization program may automatically open when you insert a memory card into you card reader. This provides an easy way of importing your pictures into your photo album. If you don’t want to import photos using the program, you can simply close the program and the card will still be mounted on your computer.

Once you decide to remove the card, make sure you unmount or “eject” the disk before physically removing the card. This will help prevent the data on the card from becoming corrupted.

RAW

Friday, December 12th, 2008

Most digital cameras process and compress the pictures you take immediately after capturing the image. This can be helpful, as it keeps the file sizes low (using JPEG compression) and takes care of color correction, including white-balance, tint, and exposure, so you don’t have to. However, some people, such as professional photographers, prefer to have more control over how each image is processed. Therefore, many high-end cameras have the ability to shoot in RAW mode. This mode does not compress the images at all and leaves them completely unprocessed.

Because Camera RAW files are uncompressed, they take up more space than typical JPEG images. In fact, RAW files often require 2 to 3 times more space for each image captured. So, you’ll want to have an extra-large memory card in your camera if you plan on shooting in RAW mode. But since RAW photos are not compressed, you maintain the full quality of each image. This can make a noticeable difference when printing images, especially for large prints.

Camera RAW files are also unprocessed, meaning all the photo processing is done on the computer. It is like taking a film negative to a dark room to be developed. The RAW file is the negative and the computer serves as the dark room. With a RAW file, you have complete control over the temperature adjustments (for white-balance), tint, hue, and exposure. However, since Camera RAW files are not typical images, most image-viewing programs will not open them. Therefore, most camera companies include Camera RAW editing software with their high-end cameras. These programs allow you to open RAW files, do the necessary processing, and save them in common image formats such as bitmap, TIFF, and JPEG.

While shooting in Camera RAW mode offers a lot of control over your photos, it takes additional software and extra time to open and edit each picture you take. For most casual photography, using the camera’s built-in processing is the most suitable option.

Bluetooth

Friday, December 12th, 2008

This wireless technology enables communication between Bluetooth-compatible devices. It is used for short-range connections between desktop and laptop computers, PDAs (like the Palm Pilot or Handspring Visor), digital cameras, scanners, cellular phones, and printers.

Infrared once served the same purpose as Bluetooth, but it had a number of drawbacks. For example, if there was an object placed between the two communicating devices, the transmission would be interrupted. (You may have noticed this limitation when using a television remote control). Also, the Infrared-based communication was slow and devices were often incompatible with each other.

Bluetooth takes care of all these limitations. Because the technology is based on radio waves, there can be objects or even walls placed between the communicating devices and the connection won’t be disrupted. Also, Bluetooth uses a standard 2.4 GHz frequency so that all Bluetooth-enabled devices will be compatible with each other. The only drawback of Bluetooth is that, because of its high frequency, its range is limited to 30 feet. While this is easily enough for transferring data within the same room, if you are walking in your back yard and want to transfer the address book from your cell phone to your computer in your basement, you might be out of luck. However, the short range can be seen as a positive aspect as well, since it adds to the security of Bluetooth communication.