ARTICLE : Getting a little bit closer with your camera

 December 2002 – Getting a little bit closer with your camera

Photographing botanical and similarly small subjects successfully is a challenge despite the expensive cameras, lenses and accessories that are now available.   Acquiring the variety of equipment available does not necessarily improve the end result although it can severely erode your bank balance and give you a pain carrying it.

Numerous books detail the intricacies of macro photography, but unless you are particularly dedicated to developing this area of photography and are prepared to buy the professional equipment made for the purpose, you can bypass most of it.   You can make satisfying images with your camera provided it is a SLR (with interchangeable lenses) and explore the macro world of plants, animals and inanimate objects around you with a relatively small investment in time and money.

Close-up or macro photography consists of making a lens focus closer, and the simplest and least expensive way is to add a supplementary lens to it.   These lenses are also known as diopters or close-up lenses.   Looking like filters they screw onto the front of your camera lens and are available in standard sizes of 52 mm, 58 mm and 62 mm in diameter.   Starting price $65.

Attaching a diopter to either a fixed focal-length or zoom lens increases the close-up range of the particular focal-length, or in other words, the subject appears enlarged and closer in the view finder.   As diopters generally come in sets of three with powers indicated by +1, +2, +4, individual filters can be selectively combined or all used together for the desired magnification.   Each number indicates an increase in magnification, however the quality may drop off if all three are used together.   Depending on the quality of the diopter you may find that the sharpest point of focus is in the middle of the frame with a blurring towards the edges.   Check the lenses for this when considering purchase.

One of the laws of optics is that as magnification increases, depth of field decreases.   Diopters (and expensive macro lenses) have a very limited depth of field, i.e.   the distance between the front and rear points in your image that is in focus.   To maximize this distance, or depth of field of focus, you can use the smaller f-stops, i.e. f11 upwards to f22, but that will mean that the shutter speed will be very slow and any movement will create a blur.   The blur resulting from hand-holding the camera can be overcome by using a tripod, but if there is a breeze causing the subject to move, a fast shutter speed is required.   1/125th of a second is a safe speed.

However you may not be able to use a small f-stop to maximize the depth of field because of insufficient light which requires you to use the larger apertures.   Crouching over mosses or orchids in awkward places contributes to cutting out precious light but may be unavoidable, and this in turn forces the use of a slower shutter speed, which in turn could contribute to a blurred image.

The solution to the problem of insufficient light is to provide some artificially.   This could be done by using a flash (an option not explored here because of its complexity and expense) or simple home-made reflectors.   A reflector is simply a piece of corrugated or plain cardboard covered with aluminium foil that has been crumpled and then mostly smoothed out.   Crumpling gives a nice diffused highlight.   A covering with a plain, uncrumpled foil will create more of a spotlight effect.   Two reflectors of any convenient size will not only reflect more light when needed, but can be also used to reduce harsh shadows or to highlight the main subject to make it stand out against the backdrop.   Unwanted areas of light creating an uneven backdrop can be eliminated by placing a person or object in the way, thereby casting a shadow which can then have more even light reflected back into it with the reflectors.

Once in the field a few techniques and tips will help improve close-up photography:
• Controlling movement can be achieved either by using shutter speeds of 1/125th of a second when hand-holding the camera or by using a tripod.   Inexpensive ($9.95+) and simple pocket-size tripods, no more than 618 cm high, come in the form of a spike or three flexible legs.   A taller extendable one is available for $24.95.   All are light and easy to carry.
• Paralleling the subject is ensuring that the film plane, i.e.   the camera back, is parallel to the subject.   Find the plane of focus for your subject by examining it through the lens to find which angle will include all or as much as possible of it in the available depth of field.
• Choosing the essential elements ensures that the defining parts of the subject are in focus.   This is especially relevant if the entire subject cannot be fitted into the depth of field.
• The depth of field button, if your camera has one, is extremely valuable.   When depressed it will show an image to be in focus though it appears blurred through the lens.   This is because depressing it shows the actual focus when the shutter is tripped.
• Overcast days are ideal for plant photography.   Shadows disappear because the sky becomes one big reflector.

(John Shaw has published many simple, well illustrated, instructive books on photographic techniques that are worth buying or browsing at our libraries)

Sunita Singh