A digital camera focuses light through a lens or a series of lenses onto a sensor, which records the image electronically. This electronic information is then converted into binary digital data, and stored on a fixed or a removable device for being read by a computer. This is, of course, a simple explanation of how digital cameras work.

In practice, most digital cameras use a charge coupled device (CCD) as an image sensor. Some digital cameras use a complimentary metal oxide semiconductor (CMOS) instead. Both these sensors convert light into electrical charges, which are transferred to a storage disc.

The sensors also filter the light into the three primary colors and then combine them to create the full spectrum. The more expensive cameras use three sensors. Each of them has a filter of a different color.

Aperture and shutter speed is used to control the amount of light that reaches the sensor. The aperture setting is automatic in most digital cameras. Some cameras also allow manual control, for professionals and enthusiasts. The shutter, in contrast, is set electronically.

The digital cameras use four kinds of lenses. These are: fixed-focus, fixed-zoom lenses; optical-zoom lenses with automatic focus; digital-zoom lenses, and replaceable lens systems. The fixed focus and fixed zoom lenses are used in inexpensive cameras while the optical zoom lenses have both wide and telephoto options. The digital zoom lens culls pixels from the central part of the image and enlarges them to fill the frame. However, this can at times result in a grainy or fuzzy image.

Most digital cameras have an LCD screen to view the image. For better viewing or printing, the image needs to be transferred to a computer. The quality of the image depends on the resolution of a digital camera, and is measured in megapixels. The higher the resolution, the better is the image quality.

The resolution is also important in deciding the size of printed photographs. A 1 megapixel digital camera will produce images that are good for e-mailing or posting on the Web. This is because their resolution is low. The images taken from a 2 megapixel camera are suitable for 4×5 inch prints while those taken from a 4 megapixel camera can produce 16×20 inch prints.

The early digital cameras used to store images on memory devices within the camera. These were then transferred with the help of cables to computers. Today, most digital camera makers provide reusable and removable storage devices. These include SmartMedia cards, CompactFlash cards and Memory Sticks. Some other removable storage devices include: floppy disks, hard disks, or microdrives, writeable CDs and DVDs. This has considerably enhanced the volume of visual data that can be stored.

A digital camera generally provides three digital storage formats. These are: JPEG, TIFF and RAW. You need to understand what these digital image formats are; only then you will be able to get a high quality photograph.

The RAW mode, as the name suggests, is a picture format where the camera has made no changes. The picture has been stored as it is. This means that each and every pixel that was captured by the camera is now on the image. You can now download this image on your computer for processing.

However, when you do so you will notice that this is a very large image, probably a few MBs. This means that you will need a very large storage area or memory space if you are going to shoot images in RAW format. Your advantage is that you can sharpen, size, or crop the picture without losing any picture quality.

But your disadvantage is the file size. You cannot transmit it easily because it needs high bandwidth connections. Also, you can shoot very few photographs if you select the RAW mode. After that, you have to change the memory card or make space by erasing a few photographs.

Also, this mode is generally not accepted by the publishing industry because it produces a 12-bit image. The photographer needs to modify it using photo-editing software before submitting it for publication.

The TIFF mode is a better mode. There is no picture loss, and the picture is also acceptable to the publishing industry since it is in an 8-bit mode. The image takes relatively less storage space as compared to the RAW format, and is very suitable for any changes that need to be made using photo-editing software.

However, it still has some drawbacks. These pertain to file size, which is still very large and can choke small e-mail boxes. You also need more memory cards if you are using TIFF images during a photo shoot.

The JPEG mode is the compression format. It not only reduces the size of the photograph but it also lowers the quality of the picture. That is why it is called the ‘lossy’ mode. A lot of pixels are lost when the photograph is changed to the JPEG format. This makes the image less suitable for photo-editing.

The advantage is that the JPEG images take less space to store. They are easier to transmit and can even be sent over dial up connections. You also can shoot more photographs with the same amount of memory space. This format is especially suited for amateur or family photography.

Canon PowerShot A590IS Highlights

8 megapixels with 4x optical zoom and optical image stabilizer With the PowerShot A590 IS, dramatic, personal pictures have never been easier to shoot and share. The 8.0-megapixel design lets you create impressive high resolution images of family and friends you’ll be proud display. The genuine Canon 4x zoom lens moves you in for powerful close-ups — like a bird in flight or a child’s winning goal — at the touch of a button. Plus, Canon’s highly sophisticated Optical Image Stabilizer keeps every shot absolutely steady even when you’re not.

2.5-inch LCD screen The camera’s 2.5-inch LCD screen gives you the big picture, whether you’re shooting, reviewing or showing off your images. This high-resolution screen offers a crisp, clear and bright picture. It also features Night Display for easy viewing in low light.

New Easy Mode simplifies operation Even if you’ve never picked up a camera before, with Canon’s new Easy Mode you can take inspiring, dramatic pictures that will impress everyone. Once you choose Easy Mode, the PowerShot A590 IS handles all the details automatically. It automatically sets every camera control including the flash to reduce blur and improve image quality. So you get pictures that are bright, clear and natural just by pushing a button. Best of all, you can relax and concentrate on what really counts — your subject.

Selectable shooting modes With 19 Shooting Modes including 7 Special Scene Modes, you’re ready for whatever shot comes your way.

DIGIC III Image Processor With DIGIC III, your images boast superior quality, the camera operates at top efficiency and battery life is enhanced. What’s more, DIGIC III enables Canon’s Face Detection Technology and Red-eye Correction to give you better, more true-to-life people shots. Simply press the Shutter Button halfway down, and the camera automatically pinpoints the faces in the scene and chooses the ideal focus point. The camera controls exposure settings and flash to keep every face looking bright and natural. Red-eye Correction can be handled in-camera, in two ways. The entirely new Red-eye Correction during shooting uses the Face Detection Technology to recognize and remove red-eye from flash images as they’re taken, before the file is written to the memory card. It’s also possible to correct red-eye during image playback, using simple settings in the A590 IS’s menu.

iSAPS Technology is an entirely original scene-recognition technology developed for digital cameras by Canon. Using an internal database of thousands of different photos, iSAPS works with the fast DIGIC III Image Processor to improve focus speed and accuracy, as well as exposure and white balance.

Face Detection Technology Canon’s powerful Face Detection Technology delivers even better results with the new A590 IS. The Face Detection Technology continues to recognize faces in a scene, and concentrate exposure (daylight or flash) and focus upon them. But the A590 IS adds more: Face Detection WB means the camera concentrates upon faces when calculating white balance for the best possible skin tones. Face Select and Track lets the A590 IS user highlight one face among several in a scene, and the camera concentrates on that person, even as they move around the scene. Face Detection Technology is a powerful contributing factor in Canon’s new Motion Detection Technology.

Red-eye Correction Red-eye Correction provides three options for removing red-eye from subjects in flash pictures.

• The new Red-eye Correction during shooting actually identifies and corrects red-eye in human subjects as pictures are taken.
• The A590 IS can be set to automatically detect and correct red-eye during image playback.
• The user can manually locate any red eyes in a scene during image playback on the LCD screen, and command the camera to remove them.

High ISO The PowerShot A590 IS features ISO 1600 and High ISO Auto settings that reduce the effects of camera shake and sharpen subjects in low-light situations, giving you greater shooting flexibility.

Motion Detection Technology automatically reduces blur Life doesn’t stand still for picture-taking. That’s why Canon included its advanced Motion Detection Technology in the PowerShot A590 IS. This sophisticated feature works in the background to instantly evaluate how fast your subject is moving. Then it automatically selects and sets the optimal exposure and ISO settings to keep everything looking sharp and clear. So whether you’re shooting a bride walking down the aisle, a ballet recital or even a child’s soccer game, you can relax and shoot with confidence knowing you’ve got the picture you intended.

Accepts Wide-Angle and Telephoto Converter Lenses To expand your creativity, the PowerShot A590 IS is compatible with shooting accessories such as wide and tele converter lenses, High-Power Flash designed for all of the PowerShot models.

Product Description

Product Description
The PowerShot A590 IS will astound you with its power-packed performance and impressive value. It’s got 8.0-megapixels, a 4x optical zoom, an Optical Image Stabilizer and a large 2.5-inch LCD. A range of shooting modes - from manual to automatic including Canon’s new Easy Mode - make picture taking carefree. A DIGIC III Image Processor with Enhanced Canon Face Detection assures natural-looking results, while Motion Detection Technology reduces blur. For added creativity, attach wide or telephoto converter lenses. ISO Sensitivity - Auto, High ISO Auto, ISO 80/100/200/400/800/1600 equivalent Built-in ElectronicFlash - Auto, Red-eye Reduction, Auto Red-eye Correction, Flash On, Flash Off; FE lock, Slow Synchro Flash Range - 12 in.-11 ft./30cm-3.5m (W), 12 in.-7.2 ft./30cm-2.2m (T) (when sensitivity is set to ISO Auto) Shooting Modes - Auto, Easy, Camera M, Portrait, Landscape, Special Scene (Foliage, Snow, Beach, Sunset, Fireworks, Night Scene, Aquarium), Indoor, Kids & Pets, Night Snapshot, Movie Storage Media - SD/SDHC Memory Card, MultiMediaCard, MMC Plus Card, HC MMC Plus Card - Suggest optional 1GB or higher for practical use File Format Design rule for camera file system, DPOF Version 1.1; JPEG Compression Mode - Still Image - Exif 2.2 (JPEG); Movie - AVI (Image - Motion JPEG; Audio - WAVE (Monaural)) Number of Recording Pixels - Still Image - 3,264 x 2,448 (Large), 2,592 x 1,944 (Medium 1), 2,048 x 1,536 (Medium 2), 1,600 x 1,200 (Medium 3/Date Stamp), 640 x 480 (Small), 3,264 x 1,832 (Widescreen); Movie - 640 x 480 (20 fps/20 fps LP), 320 x 240 (30 fps) available up to 4GB or 60 minutes, 160 x 120 (up to 3 minutes at 15 fps) Uses 2 AA Batteries - Shooting Capacity for Still Image - approx. 220 shots (AA-size Alkaline Battery), approx. 500 shots (AA-size Ni-MH Battery); Playback Time - Approx. 540 min. (AA-size Alkaline Battery), approx. 660 min. (AA-size Ni-MH Battery)

Product Features

Technical Details