Chapter 13
Macrophotography
Macrophotography is taking larger than life photographs with normal photography
lenses. It is also called close up photography. To do this sort of thing you will likely need
a tripod or other steady rest and macrophotography equipment or a digital camera with
macro compatibility.
Macrophotographs can be made with: extension tubes; bellows, lens reversing ring,
macro lens, and diopters or filter-like adapters.
Many digital cameras have a macro or super macro lens built in. On these cameras the
macro setting will focus to seven or eight inches. The super macro setting will focus to
one-inch or so. These cameras make the taking of macrophotographs a pleasure as all
focusing and exposure is taken care of without intervention, usually, by you.
Extension Tubes
Extension tubes have no optics they are installed between the camera body and your
lens. Their function is to increase the distance from the camera body to the lens. This
allows the lens to focus sharply at distances closer that what it would normally focus at
without the extension tube. One great advantage is that you maintain the quality of
your original lens.
Automatic extension tubes will allow all the cameras auto-focus and exposure functions
to remain in effect.
In any set of extension tubes you will find three or perhaps five separate units. The
extension tubes themselves will be three separate lengths and older tubes may have
removable ends that fit into camera and lens. Late model tubes will likely be of the three
unit type. The units will be listed in terms of their length in millimeters. Something like
12mm, 20, and 36mm will be found in the directions.
Some manufactures allow you to purchase these separately. Which is nice if you don't
need the full range of functionality. Before you purchase these things be sure that they
will offer the functionality that you want with your particular camera. Not all extension
tubes are automatic. Should you purchase non automatic extension tubes you will be
relegated to that no man's land of manual mode.
Bellows
A bellows is just what the name implies it is an adjustable, variable length extension
tube. With a bellows you attach the camera to one end, the lens to the other and simply
crank the thing back and forth until you have the composition focused in the viewfinder.
You can expect it to provide magnifications up to about 4X (that's four times) life
size on the film with a standard 50mm camera lens, on a 35mm camera, and up to about
25X life size with a special bellows lens.
The bellows will be attached to a focusing rail that will likely have a tripod socket
installed.
This makes using the bellows much easier on you and on your camera body as well the
weight is not hanging from the lens mount.
With a bellows adjust the lens to obtain the magnification you want and then adjust the
rear of the bellows to focus. In this way you will not change the size of the image in the
viewfinder. This is a real advantage of using a bellows.
When using a bellows you can use this equation to calculate the exposure correction:
Lens Reversing Ring
This is one of our favorite pieces of equipment and one which has remained on my old
Nikon for years. The reversing ring has no optics. It simply has a filter mount on one end
and a lens mount on the other. You literally attach it to your camera body. Now the lens
in on backwards. With the lens on backwards it will focus down to three or four inches.
This is the most inexpensive way to do close up photography.
The reversing ring has no downside it is light in weight, very inexpensive, and can be
kept on the camera all the time. Once the lens is reversed all automatic functions are
gone. You are in that dreaded land of manual mode.
Macro Lens
A macro lens will focus much closer than a standard lend. In fact, these lenses are
designed and optimized to do just that. Modern macro lenses will do this and more; they
will focus all the way to infinity and provide superb results. Should you need a short
telephoto and a macro lens you would be well advised to look into a macro lens of about
90mm or 100mm focal length, on a 35mm camera.
For shadowless lighting consider a macro lens with a built in ring light. A ring light is an
electronic flash that encircles the lens. With the flash tube wrapped around the lens
there are no shadows. Be sure to inquire about the power supply for the ring light and if
it is not included be sure to order it as well.
Macro lenses come in several focal lengths. The 50mm - 60mm focal length, the short
telephoto or 90mm - 105mm focal length, and in the 180mm - 200mm range. These
longer lenses will produce the same magnification as a shorter lens, but at greater
distances because they have more telephoto effect. For example a 180mm macro lens
will produce a life-size image from 3.6X as far away as a 50mm macro lens.
That can be a good thing is you are photographing a snake or a little critter that may get
scared off. Also the added distance between you and the subject can be used for added
lighting, maybe an umbrella flash or perhaps a reflector.
Diopters
These devices thread on to the end of your lens like a filter would. Each one has a
different ability to provide close focusing. For maximum closeness use more than one
diopter by simply attaching one in front of another. Diopters are easy to use and will
come with a chart showing how close each one will focus and how they will respond
when they are all connected together.
Macro Exposure
With through the lend (TTL) viewing and exposure calculation of digital and film
cameras calculating the exposure is almost never a problem. To make things simple just
put on your macro tool of choice and forget about exposure as your camera with its
internal light metering system will tell you the proper exposure for the subject.
However, if you are one of those diehards that likes to do things for yourself, or are
using a large or medium format camera, then this is for you.
The following table will give you the exposure compensation for about 1/10 of life size
to 100% of life size. The term life-size refers to the size of the subject. For example if
you are photographing a marble that is one-half inch in size, then life size is one-half
inch. To create an image on the film in the camera of the marble that, the image, is
one-half inch increase the exposure four times or two stops. Remember that an
increase of one stop will double the exposure. See the chapter on exposure.
- 10% of life size: increase exposure 1.2 times or about 0.26 stop
- 20% of life size: increase exposure 1.35 times or about 0.43 stop
- 25% of life size: increase exposure 1.5 times or about 0.6 stop
- 50% of life size: increase exposure 2 times of about 1 stop
- 75% of life size: increase exposure 3 times or about 1.6 stops
- 100% of life size: increase exposure 4 times or 2stops
Using a Tripod to Photograph a Cold Bug
Almost always will you need a tripod, except for those times when your subject is
cooperative and your shutter speed is fast enough to hand hold. Certainly for those
times when you wish to copy slides with a digital camera, photograph a postage stamp,
or photograph a bug you will want a tripod.
What?
Can't photograph a bug with a tripod because the little critter runs away? Yes you
can. Just put that guy in the refrigerator or freezer for a few minutes and he, or she,
won't be in a hurry to go anywhere.
That's when you get the shot, because you planned for it. Your batteries are
charged, the lighting is ready, the camera is set up with the exposure calculated and the
focus set. All that is needed is our chilly bug. And he, or she, is ‘on ice' as they say, with
nothing to do but wait for you.
Go take close up pictures. And have fun.
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