Digital Photographer. Литагент HarperCollins USD
at their own pace. Having said that, it may be necessary to modify your shooting technique a little if you are used to a compact digital camera. This is because digital SLRs have much less depth-of-field (near-to-far sharpness) than compacts, so when you graduate to an SLR you will need to get to grips with lens apertures and how these affect depth-of-field. SLRs also have faster focusing systems than compacts, so there is less risk of shutter lag.
Finally, because the pictures are sharper than those from compacts (and digital SLR users will be expecting more from their photos anyway), it is a good idea to invest in a tripod to help avoid camera-shake in low light and to aid careful composition whenever time and space permit.
YOU CAN TAKE GREAT IMAGES ON AN AFFORDABLE DIGITAL SLR WHICH CAN BE BLOWN UP TO A3 AND BEYOND.
Many photographers want a wider zooming range or more photographic control than an ordinary compact digital camera can provide, yet they do not want the size and weight of a digital SLR.
Alternative Cameras
A ‘bridge’ camera may be the answer. These offer many of the advanced controls of digital SLRs but in a smaller and less expensive body with a fixed lens. This lens may offer a very wide zoom range, perfect for photographers who want a single, ‘all-in-one’ camera.
Camera phones are becoming more popular, but the picture quality is still not of the standard you would expect from even a basic digital camera. Another alternative is to use a camcorder – most will take stills as well as video footage —but again, image quality can be an issue.
OTHER MEDIA Most images from a camcorder are only 1–2Mb or so in size, which means that the quality is a long way short of what you get from a digital camera.
Images taken with a mobile phone look fine when reproduced reasonably small, but as soon as you enlarge them they appear ‘soft’ and lacking in sharpness.
Single lens reflex cameras enable you to change lenses to achieve a variety of effects. The camera’s standard lens will give an angle of view roughly similar to that we perceive with the naked eye, a wide-angle lens enables you to get more into the frame, while a telephoto magnifies distant objects.
Lens Properties
There are other lens properties to take into account, apart from their focal length, including the maximum aperture. The larger the maximum aperture, the more light the lens can gather. This is useful in poor light or whenever you want shallow depth-of-field in your photographs.
Zoom Lenses
In modern cameras, zoom lenses have largely taken over from lenses with fixed focal lengths (’prime’ lenses). The versatility of zooms means that you do not have to carry around a number of different prime lenses, or keep changing lenses for different subjects. However, zoom lenses do have a couple of intrinsic disadvantages. One is that their maximum apertures are lower than those of prime lenses. Whereas a 50mm prime lens might have a maximum aperture of f/1.8, a typical ‘standard zoom’ might have a maximum aperture of f/4 at this focal length.
If you want to make much impact on subjects such as birds and motorsport, you will need a super-telephoto lens like this Sigma 800mm f/5.6.
Lens Mounts
Each digital SLR brand uses a different lens mount. A Nikon lens, for example, will not fit a Canon camera. However, you do not have to buy lenses made by your camera’s maker. Independent companies such as Sigma, for example, make lenses which can be supplied in different mounts according to the brand of camera you are using. These lenses are just as serviceable as those supplied by leading camera firms.
Independent Lenses Versus Marque Lenses
Lenses made by independent companies are generally much cheaper than those offered by the camera maker. The optical performance is often very good and it may be difficult to see the difference in image quality between photographs taken using a good-quality independent lens and those taken on a more expensive ‘marque’ lens. Having said that, when you buy a lens you are not just paying for image quality. Marque lenses may be better made than those from independent companies and are consequently more likely to withstand years of hard use. Their design and finish will be consistent with other lenses in the same range, and with the camera bodies which they are designed to accompany, and the lens range may include more sophisticated and specialized lenses that you cannot get elsewhere.
Of course these lenses can be used indoors as well - whenever you need an adaptable focal length.
EQUIVALENT FOCAL LENGTH Photographers using 35mm cameras are used to judging the angle of view of a lens by its focal length. However, with a couple of exceptions, digital SLRs have physically smaller sensors, so that the angle of view of the lens is reduced and it appears to have a longer focal length. You need to multiply the actual focal length by a factor of 1.5 or 1.6 to get its ‘effective’ focal length. For example, on a digital SLR a 50mm lens effectively becomes an 80mm lens.
As the focal length of a lens increases, so its angle-of-view narrows. Wide-angle lenses take in lots of the scene because they have a large angle-of-view. With super-telephoto lenses the angle is reduced to just a few degrees, and little of the scene is included.
One of the most wonderful things about photography is that you never run out of subject matter. There are so many different themes to explore. Many people start with landscapes, portraiture, travel, wildlife, children and architecture – and there is enough there to keep you going for a good many years —but the world is your oyster and you can try anything that appeals.
If you want some great landscape shots, a willingness to spend time exploring the countryside on foot is vital. The best views are rarely found at the roadside, so be prepared to get away from the car or coach. Only by going off the beaten track with a map in your hand will you discover things that many photographers miss.
Ideal Conditions
Successful landscape pictures can be taken at any time of the day, but certain conditions stack the odds of success in your favour. If you rise at dawn you are almost certain to capture some stunning images as the earth awakens after a night under the stars. From high ground you will often see veils of mist hanging in valleys, or floating gracefully over rivers, lakes and woodlands. The first rays of sunlight bathing a hillside also look stunning, and the low angle of the light reveals texture and creates a sense of depth.
USE A TRIPOD One of the keys to producing great scenic pictures is to use a tripod. It will ensure you get sharp pictures and will also slow down your picture taking – resulting in more considered compositions.