A 28mm wide angle lens is basically a wide angle lens for a 28mm camera. The book definition for wide angle lens it... "a camera lens having a wider than normal angle of view (and usually a short focal length); produces an image that is foreshortened in the centre". In may words, "A lens that you put on your camera that makes the frame (frame- what you see) wider. Ex. If your zoomed out all the way and your pointing your 28mm camera at a chair. You can see the whole chair and just the chair. If you put on your wide angle lens, you can see more. You could fit two of those chairs in your frame now. Basically, it makes your frame wider.
The wide angle lens is called a fisheye lens.
A fisheye lens IS a wide angle lens
Any lens which is wider than about 28mm all the way upto 10mm is called a wide angle. However, some lens manufacturers will add some zoom capability to their lens, e.g., 10mm to 20mm from Sigma, or 12mm-24mm from Nikon or some go even more extreme like 18mm-200mm from some manufacturers...
It depends on the range of the zoom, the size of the film format, and to some degree, the opinion of the photographer. For 35mm cameras, 50mm is considered "normal", and any lens that goes from about 50% shorter AND longer than that can be consdered a zoom that works as both wide and telephoto. An example of this school of thought is a 28mm - 80mm lens. However, for some people, that is not extreme enough to qualify. There are some "superzooms" that range from wide-angle to telephoto in the same lens - the 18-200mm range is available from Nikon and Sigma.
Fisheye Lens
heyy x a lens help you see in the light
There are a few camera lens types such as : a wide angle lens (used to capture a larger area than the area visible by a human eye), telephoto lens (opposite of wide angle), panoramic lens and so on.
heyy x a lens help you see in the light
Yes, But they will have crop factor. For example a 28mm wide lens will become a 42mm lens (35mm equivalent). Or a 200mm tele will become a 300mm.
plasma simulation using particle code
Are you sure you mean 3 metre and 6 metre lenses? They would both be incredibly long telephoto lenses (big, heavy, physically long), suitable for photographing wildlife from the other side of a National Park! You possibly mean 3millimetre (mm) and 6millimetre (mm) lenses. On compact digital cameras, a 3mm lens would be a very wide-angle lens and a 6mm lens would be a modest wide angle. On a DSLR you would be very unlikely to get a 3mm lens, a 6mm would be a very wide angle, most likely a fish-eye lens giving a round picture with great distortion. You need always to state the format a lens is used on to get a notion of whether it is wide-angle, normal or telephoto.
For shooting landscapes, a wide angle lens is best, such as the Canon EF 35mm f/1.4L USM Wide Angle Lens. It will allow you to capture more of the landscape.