Digital Photography Technology

Macro photography is getting the lens closer to the subject for greater magnification to make the picture larger is what the photographer strives for. The standard 50mm lens that comes with a camera, depending on the lens, will focus down to about 18 inches. This is acceptable for some objects, but for little critters, the inside of a flower blossom, insects, or something you can not normally see, there is a challenge awaiting you. A single lens reflex, “SLR”, with a macro photography lens, is mandatory for this type of photography. You must be able to see exactly what is being photographed. Also being able to interchange lenses is of great value.

The subject to image ratio is what determines the size of the subject or the magnification of the optics being used. A one to ten, 1:10 ratio means that if the object you photograph is 10mm in size, it will be 1mm on your film. If the ratio is 1:1, then the object would be 10mm in size. 1:1 ratios are relatively easy to obtain.

Close up, macro, and micro photography are all synonymous to each other. Ratios of 2:1 and up to 50:1 require more skills in understanding optics, and equipment becomes more critical. Ratios over 50:1 requires the use of a microscope.

Normal 50mm lenses will have a magnification of approximately 1:10. To increase magnification, the most economical way is to purchase a set of supplementary lens which will mount in front of the main lens. These will easily obtain up to a 1:1 radio.

Increasing the distance from the lens to the film or CCD sensor will also increase the ratio. This can be done with use of extension rings or tubes. These are mounted between the lens and camera. If you start with a 50mm lens, and add 50mm of extension, this will increase the size by a factor of 2 or double the size. The disadvantage is that twice the amount of light is required.

True macro photography lenses are another choice. These will focus closer and with a ratio of up to 1:1. These are available from 60mm to 200mm, but with no light loss. The downside is that these lenses are heavy, expensive, but if you are serious, money is no object. They can also be used with extension rings and tubes to increase the ratio.

The next are bellows extensions which offer infinitely variable focal lengths. Ratios up to 40:1 are possible, but these are not usable outdoors due to their size. Light loss is extreme.

Other possibilities are reversing rings which allow a lens to be mounted in reverse for increasing ratios. Lenses from movie cameras are also useable, but these all require additional and skills which are beyond anyone first starting.

With some of the above combinations of equipment, image quality can deteriorate some, but not that objectionable. Stability of the camera, lenses, and object is also extremely important. There is a direct ratio between stability and image ratio. As the ratio goes up, stability must increase proportionally. Use of strobe light will improve stability.