In Tips#2 "The Right Stuff, we listed a motor drive as a desirable camera feature. This month we will discuss how the use of a motor drive can increase your chances of getting "the" image. If you have ever stood beside a professional photographer while they are shooting sports or action, you may have noticed that they seem to shoot film like there's no tomorrow. (No, they do not own shares in Kodak or Fuji) So what do they know that the average photographer does not, besides getting someone else to pay for their film?

A few years ago a well-known photography magazine ran an article on the reflexes of birds. It was interesting in that the author had discussed the reaction times of birds and cameras. To understand the significance of this you must have a basic understanding of what happens when the shutter button is released. On most 35mm cameras, when the shutter button is pressed halfway the light meter or CPU is turned on. The camera then determines the exposure for the subject. When you press the button the rest of the way the viewing mirror will swing up, the lens will close to the pre-determined aperture, the shutter opens, closes, and the lens opens, mirror drops down, film advances. The importance of this is that there is a delay or "lag" from the time you make the decision to take the photo and the instant that the photo is actually captured. A person with quick reflexes may be able to react in say ~ 1/4 of a second. The camera then has to swing the mirror up and close the lens down before the shutter can open. (And of course associated electronic delays as well)

So what exactly does all this mean to you, the photographer? Well first off, there is a considerable delay between when you see the "perfect" image in the viewfinder and when the camera actually captures the image. During this time a highly active bird such as a warbler or chickadee can literally look left, right, up or down before the camera actually gets around to getting the picture. In fact, the bird can literally take off from the branch and be out of the frame! (We have dozens of beautifully exposed photos of empty branches from Point Pelee this year) The aforementioned article even hypothesized that a bird reacts to the sound of the mirror "slap" (when the mirror reaches the height of it's travel) and this head movement will give a blurred image when the film is exposed.

One solution is to try to anticipate the moment you wish to capture, and release the shutter slightly before. (Good luck) A better option solution is to set your camera's motor drive on its highest setting (most number of frames per second) and take a series of frames. This way as the bird is turning it's head back and forth, you will take several photos and (hopefully) you will get at least one with the "look" or profile that you desire.

Motor drive rates are quite variable with very high-speed motors being found only on high-end cameras. They typically vary from 2 frames per second to a blazing, testosterone pumping 8 frames per second! Very high rates will give slightly better results, but in practice, even slower motor drives will still give you more keepers than single frame shooting. The following sequence illustrates our point. When the shutter button was pressed for photo #1, the bird was in a perfect side profile, but by the time the shutter opened, the bird had turned it's head toward the camera. (Response to the mirror noise?) Frame number 2 the bird is again turning back to the original profile, and in frame 3 the bird is leaving! Generally the technique involves firing a series of frames in a row. This series was over in less than a second. (motor drive set for 5 fps)

If you had used single frame advance, the first photo would have been the only one captured. Note however, that the second frame is much better. The first two frames show how the birds head posture changes in just a very short period of time. It is important to realize that when shooting very active birds your percentage of "keepers" will be quite low regardless of technique used.

You might be pondering the cost of film with this technique. However, if you have traveled some distance to see your subject, the cost of the film will be small compared to trip expenses. One other advantage is that you will have in-camera duplicates for entering contests or submissions to magazines if you decide to pursue that route. Compared to the quality and cost of duplicating, in-camera dupes will be far superior.

In summary, using a motor drive can increase the number of acceptable images. Great opportunities do not present themselves very often. When they do, you want to be sure you get as many images as possible to maximize your chances of success. Thus not only can you increase the odds of capturing "the" image, but you may also capture different behaviors such as preening, yawning or singing. Should you decide to photograph a Blanding's turtle, there is little advantage to using a screaming 8 fps! Next month we will discuss our first article in a new series dealing with special lighting.

Copyright Scott Fairbairn and John Reaume

Canada Warbler shot at Point Pelee, May 1999. Nikon F5, 500mmf4

Copyright Scott Fairbairn and John Reaume

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