These article illustrates the common types of Focusing available on Cameras.
1. Manual Focus
As the name implies, this mode requires the user to manually adjust the lens for a focus. Some older SLR such as the Pentax P30 and Nikon FM2 are purely manual focus machines. For some reasons, certain photographers consider the ability to use manual focussing as a benchmark for good photography skill .
2. Single Shot Autofocus
This mode allows the lens to automatically focussed on a stationary subject. Typically, a light press to the shutter button activate this function. Most modern DSLR and digital compact cameras have this mode. The disadvantage of these is that once the autofocus is not working, using the camera can be difficult or even practically impossible.
3. Continous Autofocus
This mode allows the lens to continuously re-adjust its focus on a moving subject. Typically, a half-press on the shutter button while keeping the subject within the scene activates this function. When the shutter button is fully pressed, the camera will capture the shot. Not all modern cameras have this function.
The focal length is indicative of the optical length of a lens. It is measured in millimetres (mm). Basically there are 3 main types of lens that are classified according to their focal lengths:
1. Normal lens- this range from 35mm to 85mm. It is close to how the human eye perceive things.
2. Wide-angle lens – basically any lens below 35mm is considered as wide-angled. This ranges from 14mm – 18mm (super wide angle) to 28mm-35mm (wide angle). Wide angle lens give greater field of vision than normal lens.
3. Telephoto lens -basically any lense above 85mm is consider as telephoto. These lens allows one to capture scenes that are normally too far away.
All the different classes of lens exhibit very different characteristics.
More indepth details on the specific applications of the various lens will be covered as separate posts.
Under many circumstances, you will need to keep the camera still and stationary. Unless the photographer has super strong and steady hands, it is practically impossible to prevent shakes and vibrations to the camera. Since most of us are not robots, superman or superwoman, thus having a super strong hand grip is impossible.
One way of resolving this common photography issue, is to use the camera supporting tools such as a tripod or a monopod. A tripod is a three legged stand used to support and stabilize a camera. As the name suggests, a monopod is a one-legged counterpart of the more commonly used tripod.
On the market now are fairly new type of tripods known as flexible tripods. In terms of look, they are quite difference from the usual ones. The flexible tripods can stabilise cameras on floor levels that are uneven. It can also be deployed in positions and structures that are not possible with conventional tripods. Some can even grip and position themselves on vertical poles.
One of the original flexible tripod is the Gorillapod. Instead of having hard and stiff legs as supports, the Gorillapod has flexible legs. These legs look like gorilla grips. Perhaps that is where the name gorillapod came from.