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good quality lens enhances image quality with sharpness over the entire image, right into the corners of the photo at all f-stops. It also limits light reflections when shooting into light. In addition, if cared for properly, a lens will last for many years. On the negative side, a lens is an additional piece of equipment, adding to weight. Therefore, it is better to buy one or two good quality lenses than 3, 4 or 5 lenses of lesser quality. Every time a lens is changed there is the risk of getting dust particles on the camera’s sensor. These dust particles cause dots on the photo, particularly in the sky area where they are easily visible. A smaller number of lenses makes for less changing of lenses and therefore less dust on the sensor. What does one need? Basically, one needs a lens for general use, followed by a lens or lenses that suit one’s specific interests. There are three main streams of interest: a powerful telephoto lens for wildlife, a macro-lens for small things and a wide angle lens for landscape photography.
object stand out much better. For a “half frame” camera the 300mm f2.8 lens is also most useful as it will effectively function as a 450mm f2.8 lens. Wide angle lenses are of limited use. The 28mm end (or 17 or 18mm for a “half frame” camera) of the lens for general use is quite a useful lens. A wide angle lens has an enormous depth of field, making everything sharp from close up to the horizon. This gives great depth of field which impresses in landscapephotography. There are wider lenses (10, 20, 24mm) with a greater depth of field, but they are recommended for the enthusiast in landscape photography. Before buying a lens, make a thorough study of the different possibilities. Do not easily accept the advice of sales persons. Their motives are different. Nothing in photography gives more pleasure and satisfaction than the clear, sharp picture of a good quality lens. It’s worth the investment. A term used when referring to lenses which needs explanation is a “prime” lens. This is a lens of high quality glass and a very low f-stop (2.8 or less). They are specialized lenses for specific purposes. A classic example is a 50 or 85mm f1.4 lens for portrait photography. However, a f2.8 macro-lens and even the super telephoto lenses are also prime lenses, even though their minimum f-stop may be higher than f2.8.
The main fields covered by lenses.
For general use a lens covering a range from 28mm (wide angle) to 300mm (telephoto) is highly recommended. On full frame cameras (where the sensor is the size of the old colour slide) it will be a 28-300mm VR/IS/OS lens (which cancels out hand movement of the camera). However, on “half frame” cameras (like most DSLR cameras in use) it will be a 18-200mm lens. These “half frame” cameras with a sensor half the size of an old colour slide, magnify the image by 50%, transforming the lens into a 28300mm lens. Of the three “specialized” lenses, the 100mm or 105mm macro-lens is the most useful. It is a high quality lens which can be used for macro-work, portraits and even landscapes, and is reasonably priced. Sigma makes a very good one. The closer you get to the object, the more is magnifies. A telephoto lens is a 300mm, 400mm, 500mm and 600mm lens, large and heavy, as well as pricey. They have high quality glass, and the most popular one d ereste is probably t in states t are the 500mm s tha Midrand E et in t n e id f4 lens. These g e h Res t ing b can lenses are in join raphic clu ie Cronje. g n o n t e able to blur o H h P t with om the background contac je@gmail.c n because of a hscro very shallow depth of field, letting the primary
Test results on the sharpness of a lens. Note the lack in sharpness at f32, something that will not happen with high quality lenses.
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The Midrand Estates Newsletter - August 2013
A recommendable basic outlay of lenses. Left: a 18-200mm lens (for a “half frame” camera) or a 28-300mm lens (middle; for a full frame camera) are excellent for general use. Right: a 105mm macro-lens is a useful upgrade into the field of specialized lenses. 19