Thursday, July 31, 2008

Photo Tips - Getting in Close






Before writing this article, I thought I would “Google” the word “Macro” to see what definitions came up. As well as being a small “linking program” for use in developing computer applications (like “Visual Basic” usage in building “Access” databases), it also has a meaning when applied to photography. The most straight forward definition I found was:

“The ability of a lens to focus just inches away from an object or subject so as to produce big close-ups, sometimes even larger-than-life size.”

When I did my photography training, I was taught that in order for an image to be formed on the film the same size as the original subject, the lens has to be racked out to a distance of twice its focal length from the film plane. Provided the subject was also at the same distance in front of the lens, then the subject would be in focus. To get in even closer, then the lens has to be racked out even further. This is actually a very basic description of the mechanism behind macro photography, and if I were to be really pedantic I would also have to take into account the position of the optical centre of the lens, and where exposure is concerned, the Inverse Square Law! But enough of all this technical stuff lest you think I am just trying to impress you with the amazing depth of my knowledge.

Most good cameras these days will have a macro function, so you don’t have to worry about the technicalities touched on above. Even so, you do have to be a little more careful than when taking normal snapshots if you are going to get a good result. If you examine your camera (or even read the manual – but let’s not get carried away), you should find a switch on the barrel of the lens (usually on SLRs), or an icon on the back of the camera (a side on representation of a flower on my Canon) which when activated, brings into play the macro function. Assuming you have selected the macro mode for your particular type of camera, you need to carefully get in close to the subject. I say “carefully” because there are limits, as with everything, within which you will get a sharp result in the macro mode, and you may need to experiment a bit to see what works best. Also, when you are up very close to your subject, if you are shooting hand-held, then the smallest movement of the camera will be magnified, increasing the likelihood of getting movement blur on the photograph. If you must shoot hand held, then make sure you use a fast shutter speed. This will probably mean opening up a couple of stops on the aperture or setting the sensitivity to a higher ISO. Of course, you can only set the ISO if you are shooting digital. If you still use film, then you may need to load a 400 ISO film. Ideally, to be sure of avoiding camera shake, use a tripod.

Both the photographs featured were shot hand held. The shot of the snail was taken in rather subdued light in my front garden, and the insects on the flower shot was taken in very bright lighting conditions while on holiday in Greece, earlier this year. In neither case was I particularly looking to take a macro shot, the opportunities just presented themselves.

The great thing about macro, is that it enables you to view things in much finer detail, to enter an unfamiliar world where rich pickings may be found for the enquiring mind. Don’t just take my word for it, try it for yourself.

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