The f on a camera lens is the maximum aperture of the lens. It is sometimes listed as 1:X with X being the maximum aperture. For example:
- Canon EF 50mm f1.4 is a 50mm prime lens with a maximum aperture of 1.4
- Tamron 90mm f2.8 is a 90mm prime lens with a maximum aperture of 2.8
- Canon 70-200mm f/4 is a lens with a focal length of 70-200mm and a maximum aperture of 4.
The main function of a camera lens is to collect light. The aperture of a lens is the diameter of the lens opening and is usually controlled by an iris. The larger the diameter of the aperture, the more light reaches the film / image sensor.Aperture is expressed as F-stop, e.g. F2.8 or f/2.8. The smaller the F-stop number (or f/value), the larger the lens opening (aperture).
It is a measure of the size of the opening in the lens for the light to pass through. The smaller the f-stop the larger the lens opening, and large f numbers relate to small openings or apertures in the lens.
the F numbers usually refer to the aperture of the lens which controls how much light can enter the camera. it also affects the depth of field.
This is a Nikon lens that was originally released around 2005. AF-S stands for Auto Focus-Silent Wave Motor. This means that the lens has an autofocus motor built into it, so the cameras used with it do not have to have AF motors built into them. "DX" refers to the size of the camera sensor; the sensor has a 1.5x crop, which affects the focal length and the aperture. "18-135mm" refers to the range of focal lengths of the lens. "f/3.5-5.6" refers to the aperture of the lens; as the lens is zoomed in to longer focal lengths, the aperture gradually increases from f/3.5 to f/5.6. "ED" refers to the Extra-Low Dispersion elements, which reduce the chromatic aberration of the lens. IF stands for Internal Focus, which means the lens length does not change when focusing. The front element of this lens does not rotate when focusing either, so the orientation of front mounted accessories such as polarizing filters does not change during focusing. In photography, the "focal length" of a lens is usually stated in millimeters (mm). The higher the number, the greater the magnification. A "normal" focal length for a 35mm film camera is around 50mm. A focal length of 18mm is considered "wide angle" and 135mm is sometimes referred to as a "portrait" lens. Lenses with higher numbers (200-1000) may be called "tele-photo". The listing for a lens as 18-135mm means it is a "zoom" lens. This means the focal length can be changed by the photographer usually by turning a ring on the body of the lens. As to "f3.5-5.6", in this listing, it is the range of the maximum size of the aperture. The aperture is the opening in the camera that allows light in to take the picture. The f number -- called the "f-stop" is calculated by dividing the diameter of the aperture opening by the focal length of the lens and expressing the answer as a properly reduced fraction (with the top number a 1). The f-stop is the bottom of the fraction. For example: a camera with a 100mm lens that has a maximum aperture of 50mm, or an "f-stop" of 2 (50/100=1/2). On a zoom lens, since the focal length changes, but the aperture does not, the f-stop will change with the focal length. So, the first number 3.5 means at the lower focal length (18mm) the maximum aperture opening is 1/3.5th of the focal length, or about 5mm. The other number 5.6 means at the higher focal length (135mm) the maximum aperture opening is 1/5.6th of the focal length, or about 24mm.
An F Stop refers to a ratio used in a camera lens. It is concerned with the amount of light the lens lets in, how fast the camera can take a picture, and how much of the picture will be in focus. With pixels, it is possible to overcome some of the restrictions of film cameras. First, if you have a low f stop, like 1.2, and you have a lot of light, you can take a picture real fast. Only the object you focused the camera on will be in focus. If you use a high f stop, like 22, you will need to slow down your shutter speed. Your subject will be in focus and so will the background. The old point and click cameras had about a shutter speed of 1/125 of a second, a distance of 8 feet, and an f stop of about 8. The person would be in focus. The background would not.
Aperture refers to the opening in a camera lens through which light passes. The f-number, also known as the f-stop, is the ratio of the lens's focal length to the diameter of the aperture. A smaller f-number indicates a larger aperture and more light entering the camera.
It refers to the lens opening of a camera.
The f-stop is a number used to describe the relative opening size of the lens diaphragm during the moment of exposure. It is "relative" because the physical size for a given number (e.g. F 5.6) depends on the focal length of the lens. F 5.6 is physically larger in a 200mm lens than it is in a 50mm lens.
The setting which dictates the amount of light that enters the lens. f-stop...f-1.4
This is called the. 'f' number of the lens. A lens with a small f number is faster than one with a large f number as it admits more light. Cameras generally have lenses with f numbers of the order of 1.4 to around 16, though this does vary according to the type and size of the camera. A doubled f number (eg from 1.4 to 2.8) allows only one quarter of the light through.
The main function of a camera lens is to collect light. The aperture of a lens is the diameter of the lens opening and is usually controlled by an iris. The larger the diameter of the aperture, the more light reaches the film / image sensor.Aperture is expressed as F-stop, e.g. F2.8 or f/2.8. The smaller the F-stop number (or f/value), the larger the lens opening (aperture).
The cost of a Canon F-1 camera body is about $150 to $200. The cost of a lens for that camera can range from $200 to $5000.
shut up bit*h
an f-stop is a setting for a camera lens that determines how much light is allowed to reach the film.
The Canon EF lens will only fit Canon SLR camera bodies, unfortunately.
It has an "F" lens mount. source: http://www.dpreview.com/reviews/nikond50/page5.asp
Canon makes the best 50mm camera lens, known as the EF 50mm f/1.8mk2, 50mm f/1.4 USM and 50mm f/1.2L lenses