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A short course in Photography cont...

Focus for sharpness

The auto focus, AF, is one of the greatest features of the automatic camera. It will produce sharp pictures with a good camera lens. Point the center of the camera view finder at the subject and it will automatically focus at that point when depressingChris the shutter release button. If you're taken a portrait, focus on the subjects eyes by centering on one of them. Available light portraits are the most natural, so be sure to turn the auto flash off. This will give you the best chance to get the nicest looking photo.

You can lock in on the auto exposure (AE) and the auto focus (AF) at the same time. Simple depress the shutter release button half way down. After these are locked you can frame your subject anyway you like before completely depressing the shutter release. It is important to know that when using the AE/AF lock  you find a spot at the same distance as the subject because you're locking in your focus as well as your exposure settings.

The basic camera elements are, film speed, shutter speed and aperture setting ( if changeable). These are all related to one another and are based on the available light coming into the lens. The automatic camera will account for all these to give the proper exposure. Change one of these elements and the camera  will adjust the others accordingly.

You set the film speed the moment you place the film into the camera. Film canisters are specially coded with the films speed. Film canister with this code will have the DX mark on it. Most all new cameras today recognize this film coding. Because of this you should have an idea of what kind of subject matter you may be shooting. Then you can select the proper film by it's speed for this session.

Each of these elements is like a two sided coin. For example, let's take a look at the shutter speed. Usually we want our photos to come out as sharp as possible. Any movement by the subject or shaky hand by the photographer while taking the picture will produce a fuzzy photo. The faster the shutter speed the less chance of blurry photos due to motion. In fact the faster shutter speeds will always "stop" the motion and give sharp pictures. The flip side is, the faster the shutter speed the less light will be collected by the film. In low light conditions, dark photos ( under exposure ), will be the result.

When set on fully automatic your camera will compensate for under exposure by firing the auto flash. This is not normally what you want. With auto flash turn off the automatic settings will then correct for exposure by slowing down the shutter speed. Back to being fuzzy again. The photographer must find the right balance between the two to get sharp pictures with the proper exposure.

Here's what can be done;

  • Use faster films to get faster shutter speeds
  • Use a tripod to eliminate shaky hands
  • Flash photography to increase light and stop motion
  • Increase light with flood lamps or move subject into more naturally lit areas


Faster films will give you faster shutter speeds in low light conditions. Therefore faster films are known to give sharper photographs. What's the flip side then ? Slower films are less grainy and therefore have a much higher resolution. Slower films are necessary when you enlarge you pictures greater then the typical 4X6 inches. Films at speeds 400, 800 and greater are fast films. Films speeds at 100 and below are slow films.

The best choice then is to select slow films for bright days, portraits and still subjects. Stills and portraits may be taken with a tripod to eliminate shaky hands . Use slower films and a tripod when taken seanic pictures. This will hold the shutter open long enough to give some very nice shots. The best time to take outdoor shots is in the morning or evening when you get some very pleasing light conditions.

Select fast films for "action photography" such as sports and general everyday events. It's a good idea to keep point-and-shoot cameras loaded with 400 speed film. This gives the point-and-shoot the flexibility to be ready for anything.

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