Since you are reading this I assume you want to become a better photographer. The first step towards this goal is to get familiar with your DSLR camera. Find the mode dial on your camera and select “manual” mode instead of “automatic”. This is often shown simply as an “M”. Check your user’s guide if your camera doesn’t have the “M”. You now have control. If you look through your viewfinder and press the shutter button half way you should see some numbers along the bottom of the viewfinder. This information is very important as you must now adjust a few settings to get the picture you want to achieve. You will likely see a scale with “0” in the centre and ±1 and ±2. Use this to determine a proper exposure. Generally speaking you want the reading to be at “0”.You will also see some other numbers. These represent your shutterspeed, aperture, and ISO. Again see your camera’s user guide to learn in which order these appear. In simplified terms, getting a proper exposure is dependent upon balancing these three settings.
ISO controls the camera’s sensor’s sensitivity to light. The higher the ISO setting the more sensitive it will be to light meaning that you can shoot in low light situations. The trade off for this sensitivity is the introduction of digital noise in your photos in the form of tiny coloured dots appearing throughout you images. Because of this it is best to keep your ISO setting as low as possible to get the least amount of digital noise.
Aperture controls the size of the opening of the shutter when the picture is taken. This is a determining factor in the amount of light that reaches the camera’s sensor. The wider the aperture the more light that gets in. It may be counter-intuitive, but the higher the aperture number the narrower the opening. Aperture is represented by ƒ/ followed by the number like ƒ/1.8 or ƒ/5.6. Aperture has trade-offs as well. Wider aperture settings like ƒ/2.8 will allow more light in, but there will be less in the picture that is in focus. A narrower aperture setting like ƒ/16 will not allow as much light in, but more of the image in focus. This phenomenon is called depth of field.
Shutterspeed controls the amount of time the shutter stays open to allow the light reach the camera’s sensor. The longer the shutter stays open the more light can reach the sensor. The trade-off with shutterspeed is motion blur. In some cases this may be desirable like a photo of running water in a brook to get that silky texture in the flowing water. It would be best to use a tripod in this situation, as you would only want the flowing water blurred not the rocks or other objects in the photo.
Assignment: Get out your camera, and pick a single subject to explore how changing your ISO, aperture, and shutterspeed controls affect the way the photo looks. A running ceiling fan can be a good choice to see the effects of changing the shutterspeed. A very quick shutterspeed like 1/500th seconds will freeze the action and it will likely look like the fan is not moving. Changing to a slower shutterspeed like 1/20th seconds will make the blades blur. For aperture using a telephoto lens will accentuate the effects of different aperture settings. Wider setting like ƒ/2.8 will make whatever you have focused on sharp while the background will be blurred. Narrower aperture settings like ƒ/22 will make both foreground and background more in focus. Note how raising the ISO setting will increase the amount of digital noise is in the image especially in the darker parts of the image. When you have downloaded your photos to your computer you will be able to see how much digital noise is in your photos. It will be up to you to determine how much of this digital noise is acceptable to you.
Thanks for taking the time to read this article. I hope you enjoyed it and will return again for future articles. Please feel free to ask questions or send your comments via the contact page .