16 megapixels

Last time I explained ISO and the part that it plays in creating a digital image, and earlier I explained shutter speed. Now it’s time to wrap up the exposure trio with an aperture breakdown.

The aperture is the opening that lets light into the camera. Which then strikes the digital sensor; creating the image. For DSLR users, controlling the aperture is usually done by turning a knob. For those shooting on a point and shoot, you’re out of luck unless it’s a micro four thirds camera. Most traditional point and shoots do all the work for you, calculating the shutter speed, aperture size and the ISO so you don’t have to.

Aperture sizes are measured in f-stops. Lower f-stops (f/1.8) are a larger aperture and higher f-stops (f/22) are smaller. As I said earlier, the aperture is controlling the amount of light coming into the camera. Lower f-stops will allow you to let more light into the camera, allowing for a faster shutter speed and a shallow depth-of-field. Where as a higher f-stop will let less light into the camera, calling for a slower shutter speed to get a properly exposed image and it will give you less depth-of-field.

When should you use a wide aperture? When you’re shooting in low light conditions, or when you want a shallow depth-of-field to help draw attention to your subject. Lenses with a wide aperture are preferred by professionals for their low light performance.

I shot that image at f/2.8. Notice how the background is thrown out of focus? The shallow depth-of-field will help draw attention to your subject.

When should you use a small aperture? When you want to preserve the foreground and background, mainly when you’re shooting a landscape or if it’s extremely bright out.

That was shot at f/8 which helped keep detail in the background.

Just like shutter speed and ISO, think about what and where you’ll be shooting to help you figure out what size of aperture you should be using.

ISO, what is it? Back when I was given a Canon Powershot for Christmas I remember seeing the ISO setting and then a bunch of numbers. Since higher numbers tend to be better, I would turn my ISO to the highest that the Powershot could handle, but I was baffled at why my pictures were grainy.

Then I took an intro VCT class, and learned that ISO is how sensitive the sensor is to light and that a higher ISO will produce grainy (noisy) images. ISO is the same as film speed. Film speed is how sensitive the film is to light. Using a higher film speed will produce a grainier image, just like ISO.

An ISO of 100 is less sensitive to light than an ISO of 6,400. Also, an ISO of 100 will produce a less noisy image than an ISO of 6,400.

Here’s an example.

If you’re out shooting in the middle of the day and it’s extremely sunny out you won’t need a high ISO. Since there’s so much light out, set the ISO to 100. Because there’s more than enough light to give you a well exposed image.

However, let’s say you’re out shooting indoors at a graduation. Then you would want to turn up your ISO so you could use a higher shutter speed to capture the right moment.

How high your ISO will go depends on the kind of camera you’re shooting with. If you’re shooting with an entry level DSLR like the Nikon D3000 the highest ISO is 3,200. If you’re shooting with a more advanced DSLR, the Nikon D90 in my case, you’re ISO will be higher, 6,400, because of the different technology.

So don’t make the mistake of thinking high ISO is always a good thing. Learn the pros and cons of shooting with a high ISO on your camera to get the most out of it.

Looking back maybe I should have Googled ISO.

Love to push the shutter button? Ever wonder how many times you have pushed the shutter button?  Myshuttercount.com is an easy way to check how many shutter clicks your camera has. Just upload a recent photo and myshuttercount.com reads the exif data, giving you a precise shutter count.

Understanding shutter speed is extremely important if you have any intentions of becoming a photographer. It’s one of the most important concepts next to understanding aperture and ISO .

First off, the shutter. The shutter lets light into the camera. In the old days of film the shutter would open; allowing light to enter the camera, thus exposing the film. The same concept applies to digital photography, except replace the film with a digital sensor which takes the light and turns it into digital information.

Shutter speed is how fast the shutter opens, thus controlling how much light is hits the sensor. Shutter speed is measured in fractions of seconds the higher the denominator the faster (1/1000 is faster than 1/60).

The faster the shutter speed, less light will get in, making a fast shutter speed ideal for a super bright day. Slower shutter speeds, 1/3, will let more light in making them ideal for darker lighting conditions but be warned a slower shutter speed will pave the way for camera shake. Avoid camera shake by investing in a good tripod, so those sweet night shots will look their best. Also, slower shutter speeds will allow for motion in photos.

Here is an example of slow shutter speed

Using a shutter speed of 3 seconds and a tripod I was able to get the light trails from the fireworks, making the picture much more appealing.

Here is an some example of fast shutter speed.

I shot this using a shutter speed of 1/640 freezing the seagull in mid-flap.

So when you’re out shooting, make sure that you’re using the appropriate shutter speed for your image. Do you want a flowing stream or do you want an action shot frozen in time? Mastering shutter speed will help you get the most out of your DSLR.