A camera is basically a closed contraption that captures light (image). The fabulous DSLRs that we have today traces back its origin to vaulted rooms/chambers called “camera obscura” http://en.wikipedia.org/wiki/Camera_obscura . These gargantuan chambers have a single pin hole in one side which allows the image of their choice to enter into the room which they then use for creating illustration, paintings and the likes. Eventually Joseph Nicephore Niepce figured out a way to trap these images, only catch is that, it takes 8 hours of exposure and it soon disappears after development!
Niepce’s procedure was furthered by Louis Daguerre, who developed what was later called “Daguerrotypes”. His process ‘fixed’ the images onto a sheet of iodine-coated polished silver-plated copper which he puts in a camera for an exposure for a few minutes. After the image was “painted by light”, Daguerre bathed the plate in a solution of silver chloride. This process created a lasting image, one that would not change even if exposed to light. Every single image produced using this process was therefore an original (we have some in the archives of the MSU art museum but they are only displayed upon request). Because they need longer exposures (maybe because of the poor light sensitivity and they use tiny pinholes), early images in the 1800s are mostly still – sometimes, even when there were people in the scene, they don’t get captured because they move and don’t stay in one place long enough (because the lens is open for a loooong time)! Later, there were even contraptions developed for the back and the neck to hold the head in position for a longer time :)
Trivia: you can actually capture images using cereal boxes, beer cans, or even just your mouth (if you can keep it shut long enough)! This is what is called pinhole photography. (For more info, visit: http://www.pinholephotography.com.au/html/index.html)
Now, why mention this bit for a topic on shutter speed??? Well, aside from appreciating photography’s historical roots, it is important to take note that from the most ancient of image-capturing devices to the most sleek, digitized forms that they have become today, camera performance remains largely dependent on the amount of light that enters the device (as controlled by aperture and….*drum roll* tadaaaan!…..shutter speed!) and how sensitive is the material that receives it. Basically, your EXPOSURE.
Shutter speed is basically the length of time that the shutter is open. As previously mentioned, together with aperture, the shutter speed controls the amount of light that reaches the digital sensor (or film). Shutter speed settings are in seconds or fractions of a second: 1 sec, ½, ¼, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, and so on (check what range your camera has). Each setting lets in twice as much light as the next faster setting, so the smaller the fraction the faster the shutter speed and vice versa.
Other than for the purpose of finding the correct exposure, shutter speed is also manipulated in order to capture motion as desired, to add impact to the message being conveyed through the captured image.
A fast shutter speed (maybe starting at about 1/250 sec) can freeze motion which might be ideal for sports action, or any situation that snappy images will be necessary. High-speed photography could be an extreme example, but is surely interesting as shown in this set of samples:For more inspiring examples check this link: http://www.smashingapps.com/2010/01/17/40-stunning-examples-of-high-speed-photography.html
Here’s a DIY link for high-speed photography too http://www.diyphotography.net/diy_high_speed_photography_at_home
Sometimes, situations call for longer exposures. Setting the camera in slow shutter speed can show motion and produce interesting results (especially when it delivers what we had in mind!). Leaving the shutter speed long enough will capture all available light and the progress of motion as shown in the examples below.
Click this link for a sample tutorial on long exposures: http://digiphotomag.com/articles/how-to-a-primer-on-long-exposures/ Remember to match the appropriate aperture and/or ISO when targeting a specific shutter speed. Because long exposures are vulnerable to even the tiniest of shakes on the camera, you can opt to set your cam in timer, use a tripod, and if possible, a sandbag or any safe weight.
Panning the camera – or moving it in the same direction as the subject’s movement during the exposure is another way of showing motion. The background will be blurred, but the subject will be sharper than it would be if the camera was held steady.
Here’s a sample tutorial on panning: http://www.digital-photography-school.com/mastering-panning-to-photograph-moving-subjects
There’s definitely a lot more that’s not covered here! Please feel free to share additional tips, suggestions, and links in the comment section of this post.
Assignment: Test your own self-limitations (time, skill, creativity)! Submit images using fast shutter speed (1/125 or greater), slow shutter speed (1/15 or less) and if you feel inspired, experiment on panning too! The subject can be anything but must be theme-appropriate such that the shutter-speed settings would be purposive :)