Posts Tagged ‘canon a590 product feature’

How digital cameras work

Tuesday, February 10th, 2009

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.

Digital image format decides picture quality and storage space

Friday, February 6th, 2009

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 A590 Product Features and Technical Details

Wednesday, January 28th, 2009

Product Features

  • 8.0-megapixel CCD captures enough detail for photo-quality 16x 22-inch prints
  • 4x optical image-stabilized zoom
  • 2.5-inch LCD screen; Face Detection
  • New Easy Mode simplifies operation
  • Captures images to SD memory cards (not included); powered by AA batteries

Technical Details

  • Brand Name: Canon
  • Model: B0011ZCDKS
  • Optical Sensor Resolution: 8 MP
  • optical_sensor_technology: CCD
  • Optical zoom: 4 x
  • maximum_aperture_range: F/2.6-5.5
  • Minimum focal length: 5.8 millimeters
  • Maximum focal length: 23.2 millimeters
  • Lens Type: Zoom lens
  • optical_sensor_size: 1/2.5″
  • Included Flash Type: Built-in flash
  • Display Size: 2.5 inches
  • light_sensitivity: ISO 100, ISO 800, ISO 400, ISO 200, ISO 80, ISO auto, ISO 1600
  • Image types: JPEG
  • Shooting Modes: Frame movie mode
  • Exposure Control Type: Beach, Kids & pets, Night snapshot, Snow, Landscape, Portrait mode, Aquarium, Fireworks, Night scene, Sunset, Indoor, Foliage
  • Viewfinder Type: Optical
  • Width: 3.7 inches
  • Depth: 1.6 inches
  • Height: 2.5 inches
  • Weight: 0.4 pounds