Shutter Speed & f-stops (Aperture) – still important in this automatic camera age!
Cameras are so good today, that many if not most people set them on automatic and get shooting. I admit that I do my share of that type of shooting, but it’s not when I’m at a race track. For general snapshots of the family, the auto setting is fine and a true miracle of modern technology.
If you have any desire to learn how to shoot racing photographs at a higher, more professional level you need to spend the time to learn about Shutter Speed, f-stops (Aperture) and their effect on the photos you’re taking. It’s not just a good idea, but mandatory. Don’t let the confusing numbers, etc. scare you off. It’s really not that hard to understand if you just spend a little time at it.
Here’s a basic explanation. This is not meant to be your only source on this. Keep working at it and reading more, if needed, until you really understand it. You might even consider buying a book or two. I’ll give you a few suggestions later. Also this pertains to a camera that has adjustable settings, something like a SLR with changable lenses. In the digital world there are some great ones being sold today for some pretty cheap prices.
Shutter Speed & f-stops (Aperture) are all about exposure. Exposure is the amount of light needed to properly expose your digital image sensor or film. A favorite analogy for exposure is to use the filling of a bucket of water.
The bucket is a fixed size and needs a certain amount of water to fill it, just like film, which is of a set film speed and needs a certain amount of light to capture an image. In digital photography film speed is still used even though you’re not shooting film! To fill your bucket, you can pour a small stream of water for a long time or a fast stream of water for a short time. Either way, you end up with the same amount of water. With photography, the size of the stream of the water is comparable to the f/stop, the length of time you pour is comparable to the shutter speed, and the size of the bucket is comparable to the film speed. Strictly speaking, from the bucket's point of view, it doesn't matter which combination of stream size and length of time you choose as long as the right amount of water ends up coming in. Film (or a digital image) is the same; within limits, it is indifferent to the combination of time and amount of light as long as the right amount of light eventually arrives. This situation described is a great thing, because it allows you the photographer the freedom in choosing the combination to use. Depending on the combination, you could end up with a photograph where the car your shooting is going 100mph and looks like it is standing still or the car your shooting is going 50mph and looks like it is going 100mph. You the photographer choose the outcome by using different combinations of Shutter Speeds & f-stops (Aperture).
If your confused at this point, have faith this subject is one of those things that all of a sudden it clicks and becomes clear. It will come, just don't give up.
SHUTTER SPEED
Longer shutter speeds = more light
Shorter shutter speeds = less light
The larger the shutter speed number is, the shorter the amount of time that the shutter is open. To stop a higher speed object like a race car and have the least amount of blur, you need to use a higher shutter speed number so the shutter is open shorter, thereby lessening the amount of time the subject could blur. That’s one long sentence and definitely not good English, but you get the picture. Read it over and over. If you use a smaller shutter speed number, the shutter will be open longer and the subject you're shooting will be more susceptible to blurring.
F-STOP (APERTURE)
Smaller f-stop number = larger opening
Larger f-stop number = smaller opening
The larger the f-stop (Aperture) number the greater the range of objects in focus. With a larger f-stop (Aperture) number objects might be in focus from 10 feet to 40 feet. The smaller the f-stop (Aperture) number the shorter the range of object in focus. With a smaller f-stop (Aperture) number objects might be in focus from 10 feet to 15 feet.
Here's a little something to help you remember one of the confusing points about Shutter Speeds & f-stops (Aperture). The larger the number on both means less. Less time and less light. The smaller the number on both means more. More time and more light. Their both opposite of what might seem logical to you.
A typical bright summer day will produce an exposure of 1/500th shutter speed at f16 for the f-stop (Aperture). This is with 400 speed (ASA/ISO) film. Many of the black & white photographs you see on my website were shot with TRI-X, a Kodak film with a film speed (ASA/ISO) of 400. It should be understood that not all motorsports photographs are shot this way, but if you’re beginning I suggest you set your camera with a shutter speed of 1/500th and if your camera is able to, let it control the f-stop (Aperture). Later when you get more proficient, you can set both if you want to. To increase your percentage of “good” shots when you start out use at least 1/500th shutter speed. Later when you develop your skills you can experiment with slower shutter speeds. Don’t forget if you’re shooting a car going by (a very typical and common shot) you need to pan with the car, hopefully at the same speed of the car. I might cover panning on another posting.
Here are a couple of books that would help to further your understanding of the subject of exposure.
Exposure and Lighting for Digital Photographers Only (For Only)
