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BOOT CAMP 261 (04/02/03)
DIGITAL PHOTOGRAPHY TOP TIPS part
1
Sales of digital still cameras (DSCs) are booming, picture
quality is improving all the time and now compares very favourably with film
cameras, but it’s the partnership with the PC that makes the whole thing
worthwhile. As well as printing and archiving your pictures a PC can manipulate
images in ways that were simply not possible with conventional photography; you
can add photos to documents and web pages, email them to friends and relatives,
running costs are low and there’s no waiting for your pictures to come back from
the processing lab.
Digital still cameras are easy to use and if you’re used to a
normal film camera the transition to digital should be fairly painless – at
least when it comes to taking photographs. Nevertheless, you still need to learn
a few tricks on the PC side of things to get the most out of digital photography
and that’s something we’ll be looking at over the next few weeks, but we’ll
begin with a brief buyer’s guide for those of you that are still thinking about
taking the plunge.
The price of digital cameras has fallen dramatically in the
past couple of years but they’re still relatively expensive – compared with
compact 35mm or APS film cameras – and you should expect to pay at least £200,
and preferably a bit more for one. There are plenty of cheaper models about but
you really do get what you pay for with a DSC.
On most compact models price equates to resolution or a
camera’s ability to capture fine detail and lifelike colours. This depends on
the number of light-sensitive picture elements or ‘pixels’ on the surface of the
camera’s CCD image sensor, which is the electronic equivalent of a frame of
photographic film. A sensor with fewer than 1 million pixels (‘megapixel’) will
produce a dull, grainy looking picture. Sub megapixel cameras that double up as
web cams are okay and the picture won’t look too bad when viewed in a small
window on a PC screen or used to illustrate web pages and documents, but the
quality is not just good enough to make decent-looking prints.
Between 1 and 2 megapixels things start to improve
dramatically, the quality can be quite acceptable but the image will still look
a little coarse and prints are nowhere near as good as good as a budget or even
a throwaway film camera.
Image sensors with more than 2 million pixels is where DSCs
start to make sense and you can expect near photo quality results, though a lot
also depends on your printer (something we’ll be looking at in more detail later
on in the series). Cameras with 2.1 megapixels or better will suit most users as
an alternative to a 35mm or APS compact, and once you get over 3-million pixels
it gets increasingly difficult to tell digital pictures apart from those shot on
photographic film.
Most mid-range DSCs have a similar line up of features to
compact film cameras, namely point-and-shoot operation with automatic focus and
exposure systems; the better ones usually have a small selection of manual
controls or exposure presets, so you can get creative or cope with difficult
lighting conditions. A built-in or pop-up flashgun is more or less standard as
is a motorised zoom lens with between 2x and 4x magnification. In fact the only
significant difference is the LCD viewing screen on the rear of most digital
cameras that helps you compose your shot and review your pictures. Some DSCs
also let you capture short video movies, with sound, but it’s not an alternative
to a camcorder and the recordings usually only last a few seconds but the
resultant ‘clips’ are small enough to be sent as email attachments.
DSCs use removable memory cards to store the images but to
keep prices down the one’s supplied with new cameras usually only hold a few
images (typically one picture per megabyte of storage space on the high
resolution setting). You should therefore budget for at least one and preferably
two extra memory cards with 64, 128Mb or greater capacity. Prices vary according
to the type and size of card, and shop around, there’s usually no need to stick
to the camera manufacturer’s own brand cards.
When drawing up your shortlist be sure to check battery
running times and the cost of extra battery packs – you’ll need a least one
spare to get you through a day’s shooting. Avoid models that only use disposable
batteries like the plague; DSCs have a ferocious appetite for power and some
models can easily suck a fiver’s worth of alkaline batteries dry in a few
hours.
Finally, never buy a digital still camera on specification
and features alone, ask around and take note of recommendations (and warnings)
from other DSC owners. Make a point of visiting your local camera shop or
electronic emporium and ask to see and handle a few contenders. You should
quickly get a feel for the controls and displays and how easy, or otherwise, it
is to use. Try this little test, if you can’t work out how to switch it on, take
a picture and view the result, without prompting or if the sales assistant has
to consult the manual, then it’s too complicated and when it comes to using it
in anger you’ll probably fumble and miss that once in a lifetime picture.
Next week – part 2, handling image files
JARGON FILTER
APS
Advanced Photographic System – film camera format with easy
to load cartridges and improved creative facilities
CCD
Charge
Coupled Device -- type of microchip used in digital cameras, web cams,
camcorders, video cameras and scanners etc. containing thousands, sometimes
millions of light sensitive picture elements (pixels)
LCD
Liquid
crystal display - flat panel video display made up of tens of thousands of
picture elements or 'pixels' that can be switched on and off to control the
passage of light
TIP OF THE WEEK
If you know a thing or two about conventional film cameras
the specifications for the lenses fitted to digital still camera may look a bit
odd. That’s because the electronic image sensors in digital cameras have a much
smaller surface area than photographic film – typically 1/4, 1/3, 1/2 or
2/3-inch across. However, there is a way to work out the 35mm ‘equivalent’ lens
size using a simple formula. Just multiply the DSC lens focal length by 9.6 (in
the case of models with a 1/4-inch sensor) or 7.25, 4.8 or 4 (for 1/3, 1/2 or
2/3-inch sensors respectively). Thus for a DSC with 2/3-inch sensor and a 9 -
36mm zoom lens the 35mm equivalent would be 36 – 144mm.
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