Camera Lenses Explained
Camera lenses help to provide direction to path of light rays, so that these rays create an image, which is as accurate as possible, on the film . The different types of lenses available, are capable of reproducing different variations of the same image. This makes it important to learn various types of lenses and their mechanism in order to use the best one as per the need. Using various camera lenses might prove to be helpful.
How do Camera Lenses Work
The manner in which light rays reach the film, determines how an image gets imprinted on it. As light rays are emitted from an object in various directions, there has to be a way to control these rays, so as to get a proper image. Lenses are therefore created for the purpose of controlling the amount of light which will eventually reach the film.
The focal length of the lens along with its diameter decides what is the maximum amount of light it can let through on to the film. To find out the lens speed, you need to divide it's focal length with its diameter. To cut down on the amount of light reaching the film, an iris is kept on the lens. You can reduce the lens diameter by closing the iris.
Calibrated rings present on lenses define different focusing distances. In case your camera has an accurate reflex viewing system, you can determine your focus by seeing through the viewfinder. If your camera does not have a good reflex viewing system, you can set your focus by manually moving and adjusting the calibrated rings.
Standard Lens
As the name suggests, standard lens records images in a standard or normal manner as visible to the human eye. There is no added distortion or a change in size of an object, while clicking pictures with a standard lens. For digital cameras, focal length of standard lenses is 35 mm, while for film cameras the focal length of standard lenses increases to 50 mm. Focal length of standard lenses in medium format cameras is somewhere in the range of 75 to 105 mm.
Short Telephoto Lens
The short telephoto lens is considered to be the best for taking portrait pictures. This lens is similar to standard lens as it does not distort images. Short telephoto lenses are also good for taking pictures from a short distance.
Long Telephoto Lens
Long telephoto lenses are considered to be excellent when it comes to enlarging or magnifying distant objects, because of their longer focal lengths. You can click a picture of an object far away, but will appear very close in the picture. These lenses are large and heavy.
A variation in long telephoto lens is the mirror lens. These lenses have a very long focal length, thanks mainly to the fact that they are made of mirrors and not glass. As light falls on these lenses, it radiates off in a 'folded' manner, thereby creating a longer focal length. Certain problems with these lenses can result in poor quality images.
Fish-eye lens
A fish-eye camera lens has the unique ability to make the image appear like it is in a fish bowl. It does this by producing a highly wide angled image and making it appear convex. Uses of this kind of lens would be - capturing a close up picture along with surroundings, and also taking funny or unique pictures.
Ultra/Wide Angle
The best use of ultra/wide lenses comes while capturing a big scene. These lenses have the ability to enlarge depth in an image, thereby helping you to highlight the foreground while capturing the background. Image distortion is inversely proportional to the width of your frame. More the width, lesser the distortion.
Macro Lens
You can capture great close-up pictures using a macro lens. Also, a macro lens will give you all the details while capturing a large picture. These lenses are not capable of giving pictures of great depth and it is therefore essential to set your focus on the most crucial part of the whole frame.
After reading the various lenses, use the acquired knowledge while taking pictures. It will surely help enhance your picture quality.
