A Beginner’s Guide to Digital Cameras

Some aspects of digital camera technology can be confusing for the beginner. We’ve tried to clearly explain some of the terms used to help you understand the technology better and to help to end the confusion. We also hope this guide will help you to choose your next digital camera. Terms like pixel, white balance, and zoom are explained below and we also look at the various types of storage media used in digital cameras.

Pixels

Pixels are the tiny, square elements that make up digital images. The term comes from ‘picture elements’ and millions of pixels in digital images make up the continuous, smooth image that you see. Cameras are categorised by pixel count. A higher number will give a better quality, smoother image and the larger the image size can be without loss of quality. Digital cameras have a pixel count between one and fourteen million, designated as 1 MP (one million pixels) to 14 Mp. Popular cameras usually have a pixel count of between 2 Mp and 5 Mp.

A 3 Mp camera will make excellent prints at 4” x 6” and reasonably good 5×7″ prints. If you need to make 8×10″ prints choose a 4 or 5 Mp camera. If you need to make bigger prints than this you will need to buy a more expensive camera with a higher pixel count. Some cameras may quote both total and effective pixels. The one to take not of is the effective pixel count as this is the number actually used in the image.

White Balance

Under different lighting conditions white can appear as blue or yellow. This needs to be adjusted to appear white in the finished image. White balance is usually automatic but there are usually manual settings if you prefer to set it yourself. Settings can be adjusted depending on the light source which may be electronic flash, sunlight, shade, tungsten lights or fluorescent lighting. Some cameras also allow you to set the white balance by pointing the lens at a piece of white card.

Sensitivity

Sensitivity settings are the digital camera equivalent to ISO settings in film cameras. On most modern digital cameras settings between ISO equivalents of 100 and 200 are standard. Some may have settings of 400 and higher end SLR cameras up to 6400. Most digital cameras automatically choose a suitable setting

Digital and Optical Zooms

In general digital cameras have both digital and optical zoom. Digital zoom works in the same way as a program to edit images and results in loss of picture quality as the image is enlarged. Optical zoom works by changing the focal length and the magnification in the same way as a zoom on a film camera and gives superior picture quality. It is always better to use optical rather than digital zoom.

Memory Cards

There are many different types and sizes of memory cards and it can be very confusing. They are not compatible with each other do it is vital to buy the correct memory card for your camera. Some of the popular types are listed below.

SD - secure digital. Small cards only 2mm thick and 24 x 32mm

CF - compact flash. Larger than the other cards these were the first cards introduced. They are the cheapest cards at the moment and are 42mm x 35mm and 3mm thick with capacities of up to 2 Gb.

Memory Sticks – Sony is the only manufacturer using memory sticks

Multimedia – the same size as SD cards but with fewer features.

Smart Media – Thinner that CF cards with no memory controller.

XD - used in Fuji, Toshiba, and Olympus cameras. 20 x 25mm and just 1.7mm thick and smaller than SD cards.

Performance is very similar for all these cards. Most DSLR cameras use CF cards which are the cheapest and have higher capacities available than the other cards. There is no real need to choose one type over another except if you have more than one device that can share cards.

Connecting to your computer

You can either connect your camera directly to your computer with a suitable lead or remove the card and place in a card reader. Almost all modern cameras use USB transfer and some newer models have firewire connectors. Card readers are cheap at between $15 and $50 and multi card readers can be used with many different cards.