The hole in the lens. The greater the hole the greater the amount of light going in.
A large hole. A small f-number. Lets in lots of light. Gives the best possible bokeh.
Different lenses allow different apertures. Generally, the more expensive lenses allow much larger apertures, such as f1.4.
Using the largest aperture possible on your lens is called "shooting wide open"
The speed that the camera takes the photo. Slow shutter speeds are more likely to see blur, fast shutter speeds will freeze the action.
The sensitivity of the camera sensor.
Think of it as the size of the glass that needs filling up.
Higher ISO are good for low light situations but you have much greater risk of grain and noise.
Focal length is the "magnification" of the lens.
Low numbers (eg. 28mm) are similar to what you eye sees. They don't give you much magnification so you can get a photo of a group of people standing right in front of you. But you wouldn't get a photo of someone a long distance away as they would appear quite tiny!
High numbers (eg. 200mm) are more like using a pair of binoculars. They give you massive magnification so you can take a photo of someone standing a hundred metres away from you. Hence why I call them a paparazzi lens!
If you have a zoom lens you will see the focal lengths marked on the lens itself.
Also known as a paparazzi lens.
A long lens is anything with a focal length of 85mm or above. However your lens might be go up that high, many cameras come equipped with a kit lens which goes up to 55mm. Don't worry, even 55mm will give you a good degree of magnification.
The sparkle in your subjects eye. Often you can see the actual light source - and the photographer! - in the catchlight..
Catchlights liven up a portrait and give the photo more wow!
The fuzzy stuff in the background that everyone loves! You get more bokeh with a large aperture, a long lens, and/or by using the Bokeh Booster techniques taught in class.
Depth of Field
The amount of stuff in focus. You might have a shallow depth of field (10cm) for a portrait, perhaps even with only one eye is in focus. Or you might have a wide depth of field (1 mile) for a landscape photo, where you want most of it in focus.
Shallow depth of field is a result of high aperture. Shallow depth of field gives you lots of yummy bokeh.
Speckles of random colour and grainy appearance to photos. Caused by high ISO - or underexposing your photo.
A photo showing the whole area you are photographing in. Usually used during learning how to use a particular technique so you can show the teacher/instructor the surroundings, light conditions and how much distance there is between your subject and other objects.
Shadows you can see that are clearly defined with a line. Occur generally in "bad light" such as direct sunshine.
The camera assumes your scene will - when everythign is melted together to one colour point - be 18% grey.
However life isn't like that!
Thus a light scene (eg. person in white skisuit standing on snow) will be darkened to get the 18% grey.
The resultant shot will be darker than in real life. To correct this you would use exposure compensation (eg. +1.0)
And a darker scene (eg. person wearing black standing against a dark coloured wall) will be lightened to try and achieve 18% grey.
The resultant shot will be lighter than real life. To correct this you would use exposure compensation (eg. -1.0)