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Understanding Digital SLR Technical Terms


A camera with more megapixels will capture more information making the stored file size greater. This can give you the freedom to  print large images with great detail or to focus in and enlarge just a portion of your shot. However, the disadvantage is that you can store fewer photos on your SD card and bigger doesn't mean better quality - you need to have great lenses and image capture sensors too.

Live View

A traditional SLR camera lets you see your shot through the view finder - normally quite small and needs you to hold the camera to your eye. A live view system allows you to view the scene on the LCD screen on the back of the camera in addition to the viewfinder. This can make it easier to compose your shot, especially if the screen has a high resolution and anti-glare coatings.

Crop Factor

This again relates to a comparison of the digital SLR to a traditional film camera. Most digital SLR sensors aresmaller than a frame of 35mm film, so only a portion of the image that passes through the lens is captured by the sensor.


It is great to have the ability to manually focus your camera. Doing this takes time and may cause some degree of camera shake. Of course, if you're composing a studio shot, this isn't a problem. It might limit your ability to capture that special unexpected moment. Auto focus systems do the work for you electronically and many cameras also allow you to choose between 3 and 9 different autofocus points within your image, creating options for more artistic interpretations of your subject. An autofocus system can have disadvantages when used to capture HD video if the whirring motor is heard on the audio track of the recording.

ISO number

The effective ISO range dictates how much ambient light you need to capture a good image without having to use a flash. Increasing the ISO setting allows you to take clear photos in dim light which can really expand your ability to be creative with your shots. Pushing this too far can degrade the image quality.

Dust Control

Dust gets everywhere. You can always wipe the outside of the lens but what about inside? Dust that lands on an SLR sensor will appear as black spots in every picture. Dust controls systems attempt to prevent and eliminate this.

Image Stabilization

The problem is camera shake which leads to blurred images. Different camera manufacturers have provided different solutions, Canon and Nikon with stabilization built into specific lenses, other manufacturers pacing the control inside the camedra body. Image stabilisation comes with a price tag. If routinely you use a tripod or take phots in good lighting conditions, this may be a feature you don't need to pay for.

Continuous Drive

Want to snap several actions shots of some fast moving action? A continuous drive lets you take multiple photos in rapid succession. Some continuos drives are faster than others...

Aspect Ratio

The digital SLR image capture sensor is a rectangle. The sides, length and width, will have a certain ratio to each other. Usual ratios are 3:2 and 4:3. This simply reflects a slightly different shape of the rectangle that captured the image.This dosn't make a huge difference until you start to get commercial prints made from your images... a 6x4 print will reproduce a 3:2 aspect ratio beautifully while a portion of a 4:3 image will be cropped on printing. If you want to print larger photos, 5x7 or 8x10, the 4:3 aspect ratio suits better.

File Formats: RAW and JPG

JPG is the standard format for digital images, and is easy to e-mail, upload and print. Many cameras have a file format that is unique to the brand of camera and designed to be used with their own photo editing software. The RAW format can offer significantly more creative freedom but again takes more storage space.