Most digital SLRs come with a mid-range zoom lens, such as an 18-55mm. Although most cameras are sold with a recommended zoom lens, there's nothing to stop you buying the camera with another lens that's more suitable for your requirements, although this will probably increase the cost of your camera outfit.
The number expressed in millimetres is the len's focal length or magnification.A 50 mm has a magnification similar to the human eye. Smaller focal length( such as 28mm and 17mm ) have a wider angle-of-view( you can fit more into the photo ), good for landscape photography, while longer focal length ( 70mm 0r 300mm ) magnify the scene with a narrower angle-of-view, suitable for wild life or sports photography, even for portrait too.
The f- number in front of the lens's focal length is the len's maximum aperture. The smaller the number, the larger the aperture. An f2.8 lens is usually preferable to an f4 lens because it lets in more light so you can work in dimmer lighting condition if necessary. If a zoom lens shows a range of apertures ( such as f 3.5-5.6 80-200mm zoom ), this means that the maximum aperture is larger at the wider end (f3.5 at 80mm ) than it is at the longer end ( f5.6 at 200mm ). In practice, this doesn't worry us too much as the camera automatically makes the exposure adjustments needed.
** I recommend starting with the widest zoom range possible, especially if you are only buying one lens. Start with a 28-80mm ( 18-55mm ), a 28-105mm or a super 28-300mm zoom.
No comments:
Post a Comment