Thursday, September 24, 2009

Tips for Buying digital cameras

Choices
Digital cameras come in many sizes, shapes, and price ranges. Since you will be living with your decision to purchase a particular make and model for many years, it is a good idea to carefully weigh the various options available before buying a camera. Break the decision down into a checklist of factors to help determine which camera is best for you. Consider image quality, performance, ergonomics, features, and price. Also consider whether you will just be taking family snap shots or something more elaborate.

First decide how much you are willing to pay for a digital camera. You may need to adjust this figure up if you want and need a lot of manual control and features. Decide on camera body size, and features that you may actually use. Then look for a camera in your price range.

Digital cameras can be grouped into four types:
Compact, Ultra compact, Super zoom, Enthusiast, and digital SLR, or D-SLR.

Compact
This is by far the most popular camera category. It represents the best value for the average user. Cameras in this group take reasonable quality pictures and have a good set of features. However, these cameras don’t have many pre features or perform as well as more expensive cameras. Unless you need a higher-end or smaller camera, you should consider this type of camera first.

Ultra compacts
Are small enough to fit into tiny bags or pockets but performance is usually sacrificed in the interest of style and size. Not a good choice if you want decent pictures.

Enthusiast
These full-sized models offer more precise controls, better lenses, and more features. They produce better images, suitable for larger prints. They often include zoom lenses, faster performance, exposure bracketing, high resolution, and manual controls for shutter speed, f-stop, and white balance. This category is a good choice if you don’t want to spend a lot of money on a more expensive camera but still want a fair number of advanced features.

Super zooms
These cameras are the same as “enthusiast” except that they include at least 10X optical zoom lenses. Some of these cameras can correct for camera shake by using image stabilization software. This is a great feature for long zooms.

D-SLR
D-SLRs are the high end of digital cameras, with true reflex through-the-lens viewfinders, interchangeable lenses, good control over exposure and color, and lots of accessories.

The many professional features and functions these cameras possess almost match those of conventional 35-mm film cameras. They also produce the best images of any digital camera type.

Avid amatures and pros are the typical users for this class of camera. However, unless you plan to use the many manual features you will not get your moneys worth. Choose a camera in this class if you want the best print quality at 8x10 or higher.

Features

Mega pixels
You would think that a 6MP camera would produce better images than a 5MP one but that is not always the case.

Mega pixels are a measure of quantity (the amount of data captured), not quality. A digital camera's image quality is not based solely on mega pixels, but on an entire system. More important than the number of pixels is the actual pixel size. The bigger the pixel size the better they can record detail in the shadows and highlights. Larger sensors generally produce greater dynamic range, higher sensitivity, and better signal-to-noise ratio, mostly because they have room for bigger, more light-sensitive pixels.

So instead of just going for the largest mega pixel count when comparing cameras, ask about other important factors such as image quality.

Image quality
Image quality is a more useful measure than the number of mega pixels. Most digital cameras will produce good images, with color, sharpness, and dynamic range that will satisfy most people.

If all you want to do is e-mail your photos or make small or low quality prints at home then any digital camera will do. However, if you want good quality professionally looking 8x10 prints or larger, then the camera’s image quality is very important. Make sure you tell the sales person what you intend to do with the images so that you will be shown the most appropriate camera for your needs. A good guide is to go for at least 3MP or better and ask about image quality.

Digital cameras are slow
Most digital cameras take time to start up and be ready to shoot. They also have a recycle time between each shot. This can be annoying if you need to react fast and shoot a number of frames quickly. Make sure you can live with a camera's picture taking speed by testing it out in the store before buying.

Is the feature set right for your needs?
Taking digital pictures can be as simple as pointing the camera and pressing the shutter button. But digital camera models are available that provide as much control over exposure, color, dynamic range, and so on as you choose to use. It is recommended that you choose a camera that has the key features that you might actually use and takes better images, rather then one that has a ton of features but takes poorer quality images.

Ergonomics and style
Take time to practice holding and using a camera in the store to get a feel for how easy and comfortable it is to use. How does it feel to hold? How about the size and weight? Does it feel sturdy or flimsy? Are the controls easy to reach and understand? Are menus easy to understand and navigate? And finally, how stylish does the camera look?

Top 10 buying tips when buying digital cameras

Deciding which digital camera to buy can be difficult because of the vast array of features available. Here are some tips that should help you find a camera that meets your needs, budget, and level of photo taking experience.


  1. Select a digital camera recommended for the largest print size you're likely to print at. If you want to make 8x10 inch prints, choose a 4-mega-pixel model, though a 3MP camera will do a fair job. If you need up to 16x20 inch prints you will need an 8MP camera. If all you want is to send images by e-mail or Web posting, even a 2MP camera will do. Remember, mega pixels correspond only to image size, not quality.
  2. Make sure the camera has the right features for your needs, such as an optical zoom lens and a certain amount of useful manual controls. If you wear glasses but prefer to take pictures without them, make sure that your camera has an adjustable dioptre. This will allow you adjust the focus of the viewfinder so that you can see your subject clearly.
  3. Choose a camera with a bright LCD. This will allow you to better see the LCD image in bright sunlight. Having a large LCD screen will help you compose and review your images on the camera.
  4. When comparing costs, be sure to calculate extras that may or may not be included, such as rechargeable batteries and charger, and a large enough memory card that can hold all your pictures until you can download them to a computer.
  5. Most digital cameras come with a USB interface to transfer digital photos from camera to computer. If you will be transferring large high quality photo files, try to get USB 2.0 to speed things up.
  6. When considering digital cameras with a zoom lens, what’s important is the optical zoom distance and not the digital zoom distance. Digital zoom uses software to crop and magnify an image, resulting in a loss of image quality.
  7. If you don't know a lot about cameras, a digital camera with lots of modes and manual settings will be overkill. Don’t buy a camera that is higher in price and more difficult to use if all you really want to do is point-and-shoot.
  8. A good option, if available, is a pocket-sized instruction manual instead of one on CD. You can take it with you when you're out shooting.
  9. If you have difficulty using your hands, look for a camera with a limited number of large buttons that are easy to reach and press.
  10. Test how fast the camera performs. Look for a camera that takes 4 seconds or less to get ready to shoot and 6 seconds or less between shots.

Glossary of terms
Aperture
An adjustable opening through which light enters through the camera’s lens. The larger the aperture is, the greater the camera's photosensitivity. A smaller aperture, however, gives greater depth of field to a picture. The aperture setting is called the f-stop. A small aperture has a relatively high f-number, such as f8 or f11, and a larger aperture has a smaller number, such as f2.8. The aperture setting must be balanced against the shutter speed. The faster the shutter speed, the larger the aperture must be, and vice versa, to admit the right amount of light to the image sensor for proper exposure. These adjustments are done automatically by the camera or manually by the operator.

Compression
A process that reduces the amount of data representing an image so that the file takes up less space in your camera, memory card, or computer. Smaller files are quicker to use for e-mail and on the Web. When a file is too compressed, however, image quality can seriously suffer.

Depth of field
Indicates how much of a scene will be sharp and in focus. A greater depth of field implies an increased distance between well-focused background and foreground, with everything in between properly focused. A narrow depth of field concentrates the area of sharp focus within a small range, based on the main subject's distance from the camera.

For instance, if your subject is standing in an open field, using a narrow depth of field will make most of the scene in front and behind look blurry; only the main subject will be focused. This effect is achieved when using long zoom lens. Using a wide-angle lens will produce a greater depth of field, thereby keeping the whole scene in focus.

Image sensor
The semiconductor chip or Image Sensor is what captures the photographic image. It collects the light of a scene or subject, which it turns into digital data that we see as a photo in the camera or on the computer. There are two main types of image sensors CCD (charge-coupled device) and CMOS (complementary metal-oxide semiconductor). The CCD is the most popular. CMOS is used in very low and high end cameras.

Interpolation
A process that increases image file size and can take place either in the camera or by computer software. Interpolation is used to magnify a picture but does not improve image quality and in fact it can decrease sharpness.

LCD viewfinder
A small screen on the back of a camera that displays what the lens sees. It is used to compose the picture, choose settings, focus and frame an image in macro mode. It is also used to view photos stored on the memory card.

Mega pixel
A measure of a digital camera's resolution. A three-mega pixel rating means that the camera can capture up to 3 million pixels, or points of data.

Memory card
A removable storage device that holds the images a digital camera captures. It is a good idea to have an extra one on hand so that when one card is full it can be swapped for another allowing you to continue shooting.

Pixel
A point of data in a digital image; the word is short for picture element. A digital camera's resolution is a measure of the number of pixels it can capture on its image sensor.

Shutter speed
A measure of how long a camera allows light to fall on the image sensor (expressed as a fraction of a second). Though some digital cameras have both electronic and mechanical shutters, inexpensive models will utilize an electronic shutter to turn off the photosensitivity of the image sensors.