The easiest thing to define macro photography is a photograph with a maximum reproduction ratio of 1:1 or life size image. That is when compared to the size of the object is recorded on film or sensor is as large as the size of real objects. Suppose a fly with a length of 1 cm was photographed and projected a fall in the sensor measured 1 cm as well, then the magnifying power is 1x, or a 1:1 reproduction. But if a dragonfly with a length of 6 cm width was photographed by a camera sensor is only 2.2 cm in the reproductive 1:2,7 (obtained from 6 divided by 2.2).
Not all lenses can produce reproduction ratio of 1:1 because of the limited ability to lock the focus closest (or the minimum focus distance). Then the ratio is 1:1 lens must be able to lock the focus on objects very close so that it can capture the true size of small objects in the picture. Effort that could be done to it quite a lot, ranging from close-up filter added, turning the lens to increase the tube. Fortunately, now have started a lot of special lens 1:1 macro without the hassle of adding this and that. But there are also put up a macro lens (usually a zoom lens), though not having a maximum reproduction ratio of 1:1 and the lens is basically not a true macro lens. There is a maximum macro lens 1:3,7 only and some are 1:2. Such lenses are still useful for close-ups because it can be used to photograph objects that are close but not 1:1.
One thing to understand, when the state is able to produce macro lens 1:1 ratio means that it is the maximum value, while the photographed object is some distance from the lens of the magnifying power will also decrease (logical right ..). Then how to make sure the lens is used it is true 1:1? Easy, just picture a ruler from close range so that the scale shown is along the 22 mm exactly (assuming Canon APS-C sensor is 22 mm wide). For the lens may be located close to the ruler, depending on focal length lens (usually 40mm macro lens is fixed, 60mm, or 100mm). Managed to lock the focus when the lens is a lens that does 1:1.
So in theory, a photo with a smaller magnification of 1:1, in principle, not the macro picture, but close-ups. It's just that we're going to bother if all photos are categorized macro must be checked completely reproduction ratio. Then there is no such thing as extreme macro (or super macro), which is the image that is larger than its original size. For example, reproductive ratio is 4:1 or 4 times its normal size folding. The picture will be raising a detail of the object to be photographed, such detail in the eyes of a fly can be displayed with the super macro is.
