The "mm" marking represents the focal length of the lens as measured from the optical center of the lens to the film plane when the lens is focused at infinity. If the lens is a zoom, focal length is expressed as a range such as 28 - 80mm, which means it can be infinitely varied from one length to the other. Most zoom lenses accomplish this in part by varying the position of the optical center. The focal length or zoom range is typically indicated on the lens barrel and/or the area surrounding the front lens element.
Lenses that accept accessory filters are almost never marked with a filter diameter or series size on the lens, though screw-in filters have the diameter indicated in millimeters on the filter rim. Since many lenses are stored with a filter in place, this might easily be mistaken for a part of the lens itself, particularly with screw-in filters, which normally sit flush with the front diameter of the lens barrel.
It denotes the diameter of the lens in millimeters (mm).
*incorrect answer*
"mm" denotes the "focal length" of the lens... the distance the lens must be from the "film plane", or "sensor", to focus on infinity.
the diameter of the lens is the "f-stop". ie: f2.8.
the f-stop is a ratio of the focal lenth, to the diameter of the front element, and denotes how much light passes through the lens in a given amount of time.
focal length applies to the "zoom" of the lens, or, the size of the image on folm, whereas the fstop, is used to control exposure, and/or to limit of expand depth of fierld.
You need to buy an adaptor. Make sure you specify exactly the type of lens and exactly the camera you want to attach it to. Don't forget that there will be a large increase in magnification, i.e. your 35mm lens will give more telephoto effect on a 16mm camera. It is unlikely that the automatic functions (aperture, focus) of the lens will be carried into the 16mm camera.
2.4 mm All kidding aside: the 3.5mm lens has a wider angle than the 6mm one. This means that in a picture, you will see a larger area with the 3.5mm lens, but with the 6mm lens you'd see more (sharper) detail.
Basically most video cameras are fixed lens so you cannot put a camera lens in it unless it is specially built.
Your typical 35 mm SLR is designed to have the lenses changed while the film is in the camera, so it won't hurt a thing. I suppose it's possible that there is a camera out there that doesn't allow the lens to be changed mid-roll, but it's not likely. Usually the shutter is behind the lens, so no light will fall on the film from changing the lens.
Yes I can --> can you?
This is a Zoom lens with a focal length of between 75 and 300 mm.
Both are good for different purposes.
In standard film camera reference which is commonly used, a 50 mm lens equals a neutral value, or 1x magnification, so a 12x lens would be 600 mm.
You need to buy an adaptor. Make sure you specify exactly the type of lens and exactly the camera you want to attach it to. Don't forget that there will be a large increase in magnification, i.e. your 35mm lens will give more telephoto effect on a 16mm camera. It is unlikely that the automatic functions (aperture, focus) of the lens will be carried into the 16mm camera.
most sensors on digitals are much smaller than 35mm film frames, so the lens of 50mm acts lika a telephoto one.
This really depends on the type of camera you are looking at. If you are looking at a professional camera, chances are the lens will be much bigger than an average family camera. However, most average-sized cameras have around 50 mm lens.
I've used a 200 mm lens on a 35 mm camera for track events and football. It is a little long for portrait work, but may work OK for random candid people shots.
2.4 mm All kidding aside: the 3.5mm lens has a wider angle than the 6mm one. This means that in a picture, you will see a larger area with the 3.5mm lens, but with the 6mm lens you'd see more (sharper) detail.
That number is the focal length of the camera's lens ... which focuses light from the scene to form an image on the 'film' or CCD inside the camera. The longer the focal length of the lens, the larger (nearer) the objects appear to be in the picture. (One radian of angle as seen by the lens ===> One focal length on the film.) On the cameras described in the question, the focal length is given as a range ... "from 18 to 200 mm", and "from 55 to 200 mm". Each of these is a "zoom" lens, whose focal length can be changed over the range, enabling the user to cause objects in the picture to appear somewhat nearer or farther away.
What do you mean? It is a DSLR camera, not a lens.
Any 35 mm film camera or digital camera, usually a Digital Single Lens Reflex (D_SLR) that uses a 24 mm by 36 mm area on film or which has an image sensor (CCD, CMOS, or other) to form the image.
Any 35 mm film camera or digital camera, usually a Digital Single Lens Reflex (D_SLR) that uses a 24 mm by 36 mm area on film or which has an image sensor (CCD, CMOS, or other) to form the image.