With macro photography you can get pictures of many interesting and
beautiful subjects, such as these frozen air bubbles in ice...
Macro photography is photography of subjects that are very small,
but not so small as to require a microscope. There are many
applications for macro photography: flowers, plants, insects,
minerals, snowflakes, rime, raindrops, hailstones, icicles and such.
You can photograph anything a few millimeters in size and larger.
To do macro photography, you need bellows or extension rings that fit
your particular camera and lens mount. These rings or bellows are
mounted between your camera lens and the camera body; therefore you
need a camera that can have the lens detached. An SLR camera generally
Apart from the bellows, you need a sturdy tripod and a cable release.
Since you will be photographing small objects at some magnification,
any small vibrations of the camera will most certainly blur the exposure.
...or the internal structure of a hailstone.
It is best to use lenses ranging from 50mm (standard) to 85mm (portrait)
on the bellows. Lenses outside this focal length range are either
impractical or not very suitable.
Magnification and effective f/ratio
The bellows effectively lengthen the focal length behind the lens (the
effective focal length) while the distance of the lens to the object is
drastically reduced. Typically, the subject to photograph is only a
few centimeters in front of the lens, while the bellows or extension
rings can add more than 10 cm to the focal length.
Assuming the lens will be used with focus at infinity, the magnification
is L/F where L is the length of bellows and F is the focal length of the lens
(e.g. for a 50mm lens, F = 50mm).1
Thus, with bellows or extension rings that are 150mm in length, the
magnification factor would be 3. Without bellows, L=0 and the
magnification is 0.
The magnification says how big an object of some dimensions will be
imaged on the film (or sensor) plane of the camera. E.g. photographing
an ice crystal 1mm in size with a magnification of 4 will yield an
image of the crystal 4mm in size on the frame.
For macro photography you need a camera with bellows and lens,
mounted on a tripod with a cable release.
In addition to the magnification, the f/ratio changes as well, because
the focal length is effectively increased while the lens aperture is
the same. The factor by which the f/ratio number changes is M+1 where
M is the magnification. If you set your lens to f/8 and you use
a magnification of 3, you effectively have f/32, so a magnification
of 3 adds 4 stops to the lens aperture.2
When photographing subjects very close to the lens, any slight variations
in depth will have a major effect on the focusing of the image on the
film, because the subject distance to the lens is now much smaller than
the image distance to the lens, so small variations in subject distance
give large variations in image distance (normally this is the other way
around). You will need to set the lens at high f/ratio numbers such as
f/16 or higher to have enough depth of focus.
Other than these differences, macro photography is not any different
from normal photography. But since there is generally not much
available light due to the large f/ratio, you are bound to long
exposure times, usually several seconds. It is very important that
the camera setup (and the subject!) does not move at all during the
Because bellows and extension rings usually only reach up to about
15cm in length, you will need lenses with a short focal length if you
require higher magnifications. Typically a standard (50mm) lens is
best to use.
Reversing the lens
The photos will have better sharpness if the lens is mounted backward
on the bellows. There are special adapters available for this purpose.
Since you are using the lens in a manner that it wasn't designed for,
you can expect bad lens errors to show up, such as color fringes
(chromatic aberration), coma, vignetting, unsharpness due to
diffraction and such. To partly overcome this, there are adapters
available to mount a lens backward. Mounting a lens backward
significantly improves image quality, since with macro photography
the image distance is longer than the object distance to the lens,
while the lens has been designed to have the image distance much
shorter. Reversing the lens overcomes this.
You can set the lens at infinity or any other distance; this doesn't
matter much since the lens will move very slightly in comparison to the
long length added by the bellows. You will focus by adjusting either
the length of the bellows (there are adjustment screws on it for that
purpose), or by adjusting the distance to the subject to photograph.
Since the latter adjustment is very hard to do properly, bellows are
much better than extension rings, since those cannot be adjusted in