What is white balance?
You may have noticed that light comes in lots of different colours. Most noticeably, a sunset is deep orange, street lamps are yellowy orange, daylight is blueish, the lamps in your home are yellow (think of when you are outside at night, and you see a home lit up in the distance). Colours like red and orange are referred to as warm, while blue is cool. Our eyes are very good at adjusting for these differences. But cameras will over accentuate them. This can lead to problems. Most commonly, if you shoot images inside your home with the lights on, and no flash, they are likely to come out very orange. You can compensate for this by setting your white balance correctly. Here are the usual different white balance setting and when you should use them Auto – This lets...
Read MoreWhat is depth of field?
The depth of field is how much of the photograph is in focus. For example, a photograph has “shallow depth of field” if the foreground is in focus and the background is out of focus. In the fololwing photograph, there is a long depth of field, the sunflowers in the foreground are in focus and so are the ones in the distance. In the following photograph, there is a shallow depth of field, there is one sunflower in focus and then everything in the background is very blurred. How to control the depth of field The depth of field of a photograph is controlled by the aperture. When you use a wide aperture such as f/2.8 – you will create a shallow depth of field. When you use a small aperture such as f/22 – you will...
Read MoreShutterspeed
Right in front of the sensor of your camera, there is a shutter. This opens to allow light onto the sensor for your photograph. The shutter speed can be varied. In some cameras you can set the exact shutter speed yourself and in other cameras, it is done automatically. When there is a short shutter speed, like 1/600th of a second, most motion will be frozen. But also, not much light will get into the camera and, if all the other settings are kept the same, the photo might be quite dark unless you use a flash or there is a lot of ambient light such as a really sunny day. When there is a slow shutter speed, like 1/30th of a second, or even a second, or 15 seconds, much more light will get into the camera and the...
Read MoreWhat is aperture?
Aperture is the hole through which light travels into the camera. It sits behind the lens and in front of the sensor. As you can see in this picture, the hole is created by lots of shutters. This enables the size of the hole to change. When the hole is larger, more light passes onto the sensor, and vice versa. Somewhat confusingly, a large aperture has a number like f/2.8 and a small aperture has a number like f/22. What does aperture affect? In low light situations, we need to use a wide aperture, like f/2.8. This will enable lots of light to get into the sensor. However, it also reduces the depth of field, meaning less of the photograph will be in focus. When we use a narrow aperture, like f/22, lots of the photograph can be in focus, from the foreground...
Read MoreWhat is the difference between digital and optical zoom?
Optical zoom is a “true” zoom, like you would get on a film camera. It means that the lens extends and the optics within the camera zoom in on the scene. Digital zoom is a “crop” zoom. The camera enlarges the center of the frame and clips away the edges. You could get the same result by cropping the image on your computer and enlarging it. So what are the pros and cons of each? Optical Zoom Pros Image quality is maintained even when zoomed in Zooming in changes the perspective of the image Cons More expensive Adds weight to the camera Digital Zoom Pros Cheap Adds no weight or bulk to camera Cons Reduces image quality by literally cropping away some of your megapixel rating Could just as easily be done on a computer later if needed Artificial...
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