Photography is one of the most appealing of hobbies and is pursued by millions of people all over the world. Thanks to emerging technology, most of us nowadays boast of possessing a digital camera.
Most such modern generation cameras do not require any tweaking of settings prior to taking a picture. However, it is not the same with mechanical cameras that depend on the skills of the photographer to capture excellent images.
These mechanical cameras use light sensitive rolls of polyester films that are coated on one side by a gelatin based light sensitive chemical.
The other side of the negative has an opaque backing to prevent light from passing through. On clicking the shutter, the aperture of the camera opens for a duration of time as set by the photographer and permits light reflected off the subject to pass through an array of lenses and then fall upon the gelatin coating. Both digital and mechanical cameras are available in two types.
The mechanical ones are known as the parallax film cameras and the SLR film cameras. The old box camera that your grandfather used is a typical example of the parallax camera.
It uses 2 different lenses. One is used for viewing the image and the other one allows light to travel through to the film’s photosensitive surface. The SLR cameras, as their name suggests use a single lens for both viewing and imaging. The term SLR means “single lens reflex”. As a photographer using the box cameras you might have noticed that at times the subject got cropped up in certain areas.
This is because of the parallax error the parallax cameras are so notorious for. Try viewing a fixed object from one eye and then from the other and you will understand what parallax error is all about.
With the SLR film cameras the same lens is used to view the subject and also to expose the negative. A mirror lies between the lens and the film at an angle of 45º when the subject is being viewed. The image reflects off the lens and through the mirror directly on the viewfinder.
When the shutter is depressed, the mirror moves out of the way, permitting the light to pass unhindered on to the surface of the film. This is one of the major advantages of the SLR film cameras. With it you get what you see on the viewfinder and there are no chances of parallax error.
Apart from this, there are many other advantages of using the film cameras. With such cameras, one has the option to remove the normal lens and replace it with either telescopic, macro, or wide angle lenses. In fact the 35mm mount of the SLR cameras is so popular that there are countless filters and special effect lenses available for the same.
These can be used to create special effects on the image. The standard film used by the SLR film cameras is 35mm.