Officially you speak of a macro photo when the subject is displayed on the image sensor in real size. We call this ratio of 1: 1. The subject is then neither enlarged nor reduced. With a ratio of 1: 2, the sensor image is only half the original and we speak of a close-up. Going bigger than in reality is possible too. With a ratio like 2: 1 or higher, you can really blow up minute details.
Although you get pretty close with a lot of kit lenses, you get the best results for sharpness, color and contrast with a real macro lens with an image ratio of 1: 1. The special construction guarantees optimum image quality in the nearby area. Such an objective is usually very sharp in that range and that is necessary, because the least blur is obvious in macro photography. Incidentally, a macro lens can not only be used for macro. Many of these lenses (especially those with a focal length of around 100 mm) also perform well as a portrait lens. Always use the lens hood, even in cloudy weather or indoors. This prevents annoying reflections, which you often only see afterwards on your computer.
I myself use the Sony FE 90 mm f / 2.8 Macro G OSS and I am very satisfied with it.
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