Depth of Field
There are many technical articles written about Depth of Field and they all provide a lot of technical data, formulas and information that is far beyond what you need to know as an amateur photographer. Depth of Field (DOF) is a measurement of what, within the photograph, will be in focus. A narrow depth of field means that only a short distance before and after your subject is in focus, the rest gets more blurry the farther it is from the subject. This can be controlled with your aperture settings. Here's a simple rule of thumb: The wider your aperture (smaller F-numbers), the narrower the DOF. Controlling the aperture and the DOF will be much easier if you have an SLR camera. Just flip the camera into Aperture Priority mode and you can change the aperture size while letting your camera figure out your shutter speeds. But many pocket point-and-shoot cameras have a naturally wide DOF, and it may be impossible to get it any narrower. The Portrait Mode on your camera, which we discussed earlier, may be the only way to narrow the DOF on your pocket cameras. But there are some that can be tweaked from the on-camera menus.
If you can't do anything about your DOF, it's not the end of the world. In Landscape photography, you may want a wider DOF, depending on your subject. But with still-life, sports and portrait photography, a narrower DOF can greatly improve the quality of your photographs. A narrow DOF can also be a good indication of scale and perspective. In a two-dimensional photo, DOF is the only indicator of the relationship between your subject and other elements in your composition so long as the peripheral objects are distinguishable - don't let your DOF get too narrow. Also note that your lens will greatly impact your DOF. If you're not getting the desired DOF, try a different lens. As with anything else, it takes some practice and experimentation to master the DOF.
Select an Interesting Subject
I've left this tip for last, but I truly feel it's the most important. You can apply all of the above suggestions above, but you still will not end up with a great photograph if you don't select an appropriate subject. Unfortunately, determining what is interesting is very subjective. You may not be able to distinguish between good subjects and poor subjects until after you've developed or converted your photographs. This is where digital photography earns the bulk of its appeal as it doesn't cost you a thing to experiment and later discover the subject matter is boring. Unfortunately, film users will need to think hard before taking the picture, unless money isn't an object.
With portrait or sports photography, your subject matter is very obvious. But then you need to think about what you're trying to show. Emotion is important when staging your portraits - it needs to feel real. Smiles are common, but many people over-do it - yielding fake or goofy looking smiles. Try to get the person to laugh, and catch them in the right moment. If it's not a family portrait, other emotions are much more interesting and favorable. Try to catch them in a candid shot. Timing is everything, but you can often get some very real emotion from candid shots, especially with sports photographs.
With other types of photography, such as still-life or landscape, subject matter is very difficult to choose. You may need multiple subjects, or you may need the subject to be very subtle. Choosing subject matter becomes more of a compositional exercise than anything else. A photograph of a barn in a farm field may have a wide range of subjects including the bar, the hills behind it, a grain shed that might be within the photograph, and the corn that is relatively close to you. You need to weigh your subjects to determine which is the most important to your photograph.
Once that has been determined, apply the Rule-of-Thirds, an appropriate DOF and an appropriate framing or composition to subtly suggest which item is your primary subject. Don't be afraid to move around - sweep the area for different camera angles and viewing positions. This is a situation where you may need to determine the best composition for your subject matter after you have converted your photographs.
Subject interest is also greatly impacted by your frame of reference. A full-view photograph of a boat at the edge of a lake may be interesting. But a close-up shot of the bow or the oar-locks with a moderate DOF is going to be much more interesting. The viewer can still plainly see it's a boat, but they're seeing it from a perspective they're not used to. The subject hasn't change, but the way you use it has. Perspective greatly impacts a viewer's interest in the subject.
Final Words
Photography is more about trickery than anything else. Unlike other mediums, you're limited by the physical world. The most important thing you can take away from this article is that you are striving to provide a perspective that is different from what people might expect.
Whether you crop the picture so that you focus on a specific element, or if you take a photograph from an unusual angle, you're tricking the viewer. Humans are creatures that establish symbols - they generally know what a car is because their mind has a symbolic template for a car. If you work outside of that symbolic ideal, the viewer will naturally stand back and evaluate your work. The difference between a snapshot and a great photograph is that moment: The moment when your viewer questions what he's looking at. If you can raise that question, you're holding the viewer's attention - and that is a great photograph.
