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If you love capturing the intricate details of tiny objects, like bugs of flowers, there is no better way than through macro photography. Also known as macrography, photomacrography and macrophotography, macro photography is extreme close-up photography where the resulting photograph is much greater than the actual size of the subject. This is achieved by using special lenses, which allow you to focus very closely on the subject, like the ones described below.
A Bellow, in photography, is a pleated, expandable part of a medium to large format camera. With the success bellow garnished in macro photography, several manufacturers also produces bellows for small format camera.
The bellow allows a lens to be moved in respect to the focal plane of focusing. By moving the lens further away from the film (sensor) plane, you move its focal point closer to the lens. At the same time, you lose infinity focus, which is not exactly needed in macro photography.
There are two kinds of bellows that are usually used on cameras. These are bag bellows, which are normally used with a short focal length lens and the accordion bellows, used in the same way but with a much longer range extension. The best way to use a bellows is with a tripod to allow for more stability when adjusting the distance between the camera and the subject.
A bellows macro lens that has a short focal length of between 12.5mm to 38 mm, will provide a magnification of between x3 to x20. Because they do not have a focusing mechanism, they cannot be mounted directly onto a camera but instead they are used either with an extension bellows or a variable extension tube and a macro stand. A bellows macro lens should never be used in reverse because they are already designed for larger than life photographs.
Pros
Excellent results when used properly, provides a dark and flexible extension between the lens and the film plane.
Cons
They can be expensive, they need special focusing screens for higher magnifications, need a tripod or macro stand, not available with autofocus, must have an extension bellows to change magnification.
A close-up lens, filter or macro filter is a secondary lens used in macro photography that does not require the use of a specialised primary lens. It is the same concept as reading glasses allowing the primary lens of the eyes to focus more closely. Normally mounted on the filter thread of the primary lens, close-up lenses are sold by suppliers that manufacture photographic filters. These lenses are also commonly referred to diopters, which is after the unit of measurement of their particular optical power. You can get high-quality close-up lenses that are composed of achromatic doublets that have the ability to produce excellent images with a low loss of sharpness.
Usually, a close-up lens is marked with a +d number, which is the diopter unit or the power of the lens. The power of the lens or the diopter is defined as 1000/f and f is what the focal length is in mm. As such, a 50mm lens has a diopter of +20, which is equal to 1000/50 and a close-up lens with a +4 diopter has a 250 mm focal length, which is 1000/4. In addition, the larger the diopter value, the higher the magnification.
Pros
Close-up lenses were designed for use as telephoto macro. A close-up lens will magnify an image before it enters the main lens and there is no loss of light and actually brightens the image. Easy to screw or snap on
Cons
The glass quality of the close-up lens may not be the same quality of your camera which may cause image deterioration.
Extension tubes are also called extension rings and can be interchanged with other lenses to get a closer focus. Extension tubes extend the focal plane to gain maximum magnification. Using extension tubes requires a longer exposure time because of the loss of light. Unless your extension tube has electrical contacts, you will not be able to use the autofocus on an automatic camera meaning you will have to manually focus the camera. The newer, more expensive extension tubes come with electrical contacts but if you have an older camera, you may need an adapter.
You can get an extension tube for nearly every DSLR or SLR body that can be attached to a variety of different lenses to attain different effects, plus they do not cost as much as dedicated macro lenses. Generally speaking, the greater the minimum focal distance, the longer the focal length of the lens in fact, the lens creates a �narrow focus zone�, in which an object can be focused. For example, with a 50mm lens, the minimum focal distance is about 4 inches with a depth of field that is extremely narrow.
Pros
Enhances the lens capability, gives a degree of macro capability, allows a lens to focus much closer, allows you to convert most lenses into a macro lens for much less cost.
Cons
Sometimes using an extension tube will not allow the lens to focus to infinity, the focus range will be limited to very close focusing distance, loss of light that sometimes is the equivalent of 3 f-stops, because of the loss of light you usually have to manual focus.
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