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Diagram of a shutter - taken from http://www.braindex.com

What is a shutter?
A shutter is a device that allows light to pass for a determined period of time, for the purpose of exposing photographic film or a light-sensitive electronic sensor to light to capture a permanent image of a scene - taken from http://en.wikipedia.org/wiki/Leaf_shutter

Where is it indicated?
First of all, the shutter is built on the camera. It is not indicated on the lens. Before we move on, let us establish and understanding first. The term shutter speed is not a correct term while exposure time should be the correct term. This is because the shutter of the camera closes and opens within the same time period. Still can’t reason it out? Take your car window as a shutter and the air molecules as light. The rate at which the window(shutter) opens or closes is the same. The amount of air(light) which enters through the window(shutter) depends on how long the window(shutter) is left open. Hence, exposure time. However, for the sake of the general public, I will use shutter speed instead of exposure time. Generally, the shutter speed is displayed on the LCD of cameras. You should see figures like 1/100 or 1″. 1/100 translates into a 100th of a second while 1″ equals one second. Some digital cameras sport values like 0.4″. I suppose it means 0.4 seconds.

Where do I set the shutter speed?
The shutter speed can only be set by cameras that sport the “manual” function. Most consumer cameras however do not offer the “manual” function, the reason being to maintain the camera’s small size. To set the shutter speed, there are two possible methods. First, switch the camera mode to shutter priority (Tv) and turn/press the dial/button to the desired shutter speed. Tv mode offers some convenience as properties such as aperture and sometimes ISO is set automatically by the camera. The second method is to switch the camera to manual (M). The name says it all. With M mode, you will have to control every single aspect of the camera yourself. Turn/press the dial/button to the desired shutter speed.

How do the different shutter speeds affect my photographs?
A fast shutter speed e.g. 1/300 will freeze the motion of most objects, excluding objects that are traveling at very high speeds. A slow shutter speed e.g. 1/10 will not freeze the motion of subjects completely, creating blurry images. This is not a bad thing because using a low shutter speed would give motion to the subject in the picture. We will discuss in detail in the next question.

From the left, a waterfall taken at 1/200, 1/1600 and 1/4000.

Fast shutter speed?
As mentioned above, a fast shutter speed is usually applied when we want to freeze the subject in motion or simply to avoid handshake. For example, water droplets or maybe a bird in flight. Observe the picture above. At 1/200, the motion of the water droplets are not frozen completely, thus the image appears to have motion blur. At 1/1600 and 1/4000 the water droplets are visible because the motion has been frozen. Now, a fast shutter speed means that less light would have reached the camera’s sensors. If you don’t wish to bump up the ISO or do not have access to a lens with a big aperture, shooting under bright daylight (good lighting) will be no problem. However, the problem arises when you are shooting indoor sports and maybe a formal function. Of course, you could use a flash but sometimes you just can’t. If you have access to a lens with a big aperture and isn’t stubborn enough not to bump up the ISO, you would be fine. Of course, don’t expect a 1/4000 shutter speed indoors - not at present but maybe in the future, if technology permits.

Slow shutter speed?
Slow shutter speed? Who would want that in the first place if it causes your image to go blurry? Guess what? It does have its own advantage! Have you ever seen pictures of waterfalls whereby the stream of water looks very creamy? This is exactly how you would take the picture! Use a slow shutter speed! Of course, you would have to watch out for the exposure of your picture - make sure it is not over or underexposed. Besides that, beautiful pictures of fireworks are taken this way. Not to mention night scenery and perhaps dances. Another type of shot taken with slow shutter speed would be a panning shot, which will be discussed in the next question. Of course it is best to have a tripod along but since the invention of the Image Stabilizer/Vibration Reduction/Optical Stabilizer, it is quite possible to shoot handheld at 1/10.

Rule of Thumb
Now, let’s say you are on manual mode. You would like to know what is the minimum shutter speed for the picture to be taken at to reduce camera shake. Well, good news as there is a rule of thumb for that! Let’s say you are taking at 55mm, the slowest shutter speed you should be is at 1/55. Likewise for 300mm, your slowest shutter speed should be at 1/300. Get the logic? Of course, some of you might hand extra steady hands so you could still shoot at shutter speeds slower than prescribed. Again, the rule of thumb is not a must, but rather a guideline.

A Ferrari F1 car at the Sepang Race Circuit

Panning Shot?
Observe the picture above. Notice that the car is sharp/clear but the background is blur, suggesting motion. How do we achieve that? First, you would have to select a shutter speed that is relatively slow for the subject you are shooting. For the F1 Race, I used a shutter of 1/125 for my panning shots. Do note that F1 cars zoom past you at high speeds. Ensure that the exposure is correct. If you have the option to set the focus to “AI Servo”, do it! As the subject zooms by, focus on the subject and follow its motion! Click the trigger whenever you feel the composition is right. Just to be safe, continue following its motion until the shutter reopens again.

Image Stabilizer/Vibration Reduction/Optical Stabilizer?
A prayer answered for some photographers, the Image Stabilizer/Vibration Reduction/Optical Stabilizer has blessed photographers the ability to shoot sharp/clear pictures handheld at low shutter speeds. Most companies have decided to incorporate the stabilizing system in the lenses, thus increasing the price tag for lenses that sport the system. Sony on the other hand came up with a marketing strategy by incorporating the system in the camera body itself. Both types of stabilizing systems have its pros and cons. For further info, just google it up. Shooting with a stabilizing mechanism definitely helps provided if the subject remains motionless. Do remember to turn it off when using a tripod - some however are able to detect the “presence” of a tripod.

Image Stabilizer/Vibration Reduction/Optical Stabilizer VS shutter speed?
Given the choice, I would pick shutter speed over the stabilizing mechanism. Of course, if I had both, it would be best. Now, Image Stabilizer/Vibration Reduction/Optical Stabilizer allows us to shoot at low shutter speeds handheld. However, it does not help if the subject is in motion e.g. dancing, running. Besides that, it consumes more energy, thus reducing the number of shots you can take with a fully charged battery pack. Another blow would be the price tag. It usually costs a thousand more than its cousin that does not have the stabilizing mechanism. Just observe the EF 70-200 f2.8/L USM and EF 70-200 f2.8/L IS USM. If you favour fast shutter speeds, your only answer is to get a camera with a high enough ISO, with noise at an acceptable level or a lens with a big aperture. An advantage would definitely be the ability to freeze the motion of your subject. Besides that, it would be cheaper than its Image Stabilizer/Vibration Reduction/Optical Stabilizer counterpart - note that some lenses that have the stabilizing mechanism are quite affordable too. As mentioned, it would be best if you had the best of both worlds.

Conclusion?
Use a fast shutter speed when you want to freeze a subject’s motion or to prevent handshake. Use a slow shutter speed when you want to capture the motion of the subject, trails of light or night scenery. Image Stabilizer/Vibration Reduction/Optical Stabilizer is useful for taking pictures handheld at slow shutter speeds provided the subject remains motionless. It is however quite heavy on the wallet - note that some lenses that have the stabilizing mechanism are quite affordable too.

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