Macro Index
Macro lenses must be able to produce an image on the sensor that is at least 1:1 ie life size. Below are shown my 3 macro lenses.
From left to right they are a Nikon 60mm f.2.8, 105mm f2.8 and 200mm f4
The effective depth of field decreases as the focal length goes up, but increasing focal length also allow you to get the same magnification from further away. - useful if you are photographing a skittish animal. The depth of field is very small at such close distances in any case and so focus stacking is useful with a stationary subject. When I take a stack I use a camranger attached to the camera. It automates the focus adjustments and fires the shutter preventing me from wobbling the camera from manual interventions. The 105mm lens is probably the most versatile but the aspect ratio changes as it is focused which can be annoying. The larger the focal length the further you are away for the same shot which means the perspective changes. The 3 photos of the N gauge locomotive were taken to fill the frame similarly each time but taken in turn with the 60, 105 and 200mm lenses. With these lenses you are often so close to the subject that you block out a lot of light so a ring flash is another essential accessory. Mine is shown here and the infra-red controller that synchronises them is in the camera hot shoe. Control is such that each flash can be set at a different power, angled differently or have a diffuser fitted.
Close ups can obviously be taken with a telephoto lens producing results such as these
but a macro lens will allow one to focus at much closer distances
The next two images show how depth of field can be increased by photo-stacking
Not Stacked Stacked
Lastly these 3 photos show the changing perspective as focal length increases, the camera has to be moved further away to keep the image size the same size on the sensor as each longer focal length lens is fitted. After ach lens change I have taken the camera away along the same straight line.
60mm 105mm 200mm