Telephoto lenses between 70 — mm are very popular lenses for portraiture and product photography as well as nature and wildlife imagery. They allow the photographer to produce close crops on the subject. In the case of portraiture a telephoto allows the photographer to take the photo at a distance that does not intrude upon the subject.
These lenses provide a good range for wildlife and sports photography where the photographer is limited as to how close they can get to the subject. Close-up photography uses a specific range of lenses that allow up to reproduction. These lenses allow the photographer to focus very close to the subject and reproduce them at a life-size ratio on film or an imaging sensor.
These lenses are popular for subjects such as flowers, insects and small products. By clicking Sign Up, you are opting to receive educational and promotional emails from Nikon Inc. You can update your preferences or unsubscribe any time. Search Articles. Glossary Off On. Focal length dictates what part of the image is in focus, isolating elements in either the foreground, middle ground or background It generates visual context for your shots And it alters the visual properties of your shots.
A basic way of explaining focal length is the magnification of your lens. These performers understand the power of focal length. Some people may refer to the focal length at the lens size. Shot list with lens size StudioBinder. Long focal length used to simulate binoculars. Camera Lens Terms Explained What is a camera lens aperture?
The lower the stop number The higher the aperture wider the opening. Understanding Cameras and Lenses What is shutter speed? But for video What is Shutter Speed? Cinema Frame Rate The standard frame rate is 24fps Television Frame Rate The standard frame rate is 30fps When would I use a non-standard shutter speed? Shutter Speed Saving Private Ryan. This created a jagged look that really works well for action. Camera Lenses Explained What is depth of field? This shot has a large, long, or deep depth of field.
Camera lens specs from Blade Runner. Consider this when selecting a camera lens. Lens breathing. Camera Lens Explanation What is lens flaring? Camera Lenses Explained What is chromatic aberration? Chromatic Aberration. Camera Optics Explained What is bokeh? Camera Lens Bokeh. Cinema lenses have a dramatically higher throw than still photo lenses.
Cine lenses vs Photo lenses. Showcase your vision with elegant shot lists and storyboards. Learn More. Featured Blog Posts. Since that first camera did not capture very much light, it actually took eight hours to take a single photograph. The image was also quite blurry. So how are we able to take sharp images in milliseconds today? A camera lens. While light bounces off of objects, it can also pass through objects — but, when it does, it can actually change direction.
A camera lens takes all the light rays bouncing around and uses glass to redirect them to a single point, creating a sharp image. When all of those light rays meet back together on a digital camera sensor or a piece of film, they create a sharp image. Distance also plays a role in how camera lenses are able to zoom in. When the front piece of glass moves farther away from the camera sensor, objects become closer.
Focal length is the measurement of the distance between where the light rays first hit the lens and where they reach the camera sensor. For example, on a lens with a mm focal length, the light takes mm to be directed back into a sharp point on the camera sensor. A camera lens collects and focuses the light — but how is that information recorded? Historically, photographers were also chemists of sorts. Film is made up of light sensitive materials. When those materials are hit with light from the lens, they captured the shape of the objects and details like how much light is coming off of them.
If you're taking a close-up portrait, you might use a wide-angle lens. This lens has a much shorter focal length, so it shrinks the scene in front of you. The entire face is exposed to the film even if the subject is only a foot away from the camera. A standard 50 mm camera lens doesn't significantly magnify or shrink the image, making it ideal for shooting objects that aren't especially close or far away.
A camera lens is actually several lenses combined into one unit. A single converging lens could form a real image on the film, but it would be warped by a number of aberrations. One of the most significant warping factors is that different colors of light bend differently when moving through a lens.
This chromatic aberration essentially produces an image where the colors are not lined up correctly. Cameras compensate for this using several lenses made of different materials. The lenses each handle colors differently, and when you combine them in a certain way, the colors are realigned.
In a zoom lens , you can move different lens elements back and forth. By changing the distance between particular lenses, you can adjust the magnification power -- the focal length -- of the lens as a whole.
The chemical component in a traditional camera is film. Essentially, when you expose film to a real image , it makes a chemical record of the pattern of light. It does this with a collection of tiny light-sensitive grains, spread out in a chemical suspension on a strip of plastic. When exposed to light, the grains undergo a chemical reaction. Once the roll is finished, the film is developed -- it is exposed to other chemicals, which react with the light-sensitive grains.
In black and white film, the developer chemicals darken the grains that were exposed to light. This produces a negative, where lighter areas appear darker and darker areas appear lighter, which is then converted into a positive image in printing. Color film has three different layers of light-sensitive materials, which respond, in turn, to red, green and blue. When the film is developed, these layers are exposed to chemicals that dye the layers of film.
When you overlay the color information from all three layers, you get a full-color negative. For an in-depth description of this entire process, check out How Photographic Film Works.
So far, we've looked at the basic idea of photography -- you create a real image with a converging lens, and you record the light pattern of this real image on a layer of light-sensitive material. Conceptually, this is all that's involved in taking a picture. But to capture a clear image, you have to carefully control how everything comes together. Obviously, if you were to lay a piece of film on the ground and focus a real image onto it with a converging lens, you wouldn't get any kind of usable picture.
Out in the open, every grain in the film would be completely exposed to light. And without any contrasting unexposed areas, there's no picture. To capture an image, you have to keep the film in complete darkness until it's time to take the picture. Then, when you want to record an image, you let some light in. At its most basic level, this is all the body of a camera is -- a sealed box with a shutter that opens and closes between the lens and film.
In fact, the term camera is shortened from camera obscura , literally "dark room" in Latin. For the picture to come out right, you have to precisely control how much light hits the film. If you let too much light in, too many grains will react, and the picture will appear washed out. If you don't let enough light hit the film, too few grains will react, and the picture will be too dark.
In the next section, we'll look at the different camera mechanisms that let you adjust the exposure. As it turns out, the term photography describes the photographic process quite accurately. Sir John Herschel, a 19th century astronomer and one of the first photographers, came up with the term in The term is a combination of two Greek words -- photos meaning light and graphein meaning writing or drawing.
The term camera comes from camera obscura , Latin for "dark room. A traditional camera obscura was a dark room with light shining through a lens or tiny hole in the wall. Light passed through the hole, forming an upside-down real image on the opposite wall. This effect was very popular with artists, scientists and curious spectators. In the last section, we saw that you need to carefully control the film's exposure to light, or your picture will come out too dark or too bright.
So how do you adjust this exposure level? You have to consider two major factors:. To increase or decrease the amount of light passing through the lens, you have to change the size of the aperture -- the lens opening.
This is the job of the iris diaphragm , a series of overlapping metal plates that can fold in on each other or expand out. Essentially, this mechanism works the same way as the iris in your eye -- it opens or closes in a circle, to shrink or expand the diameter of the lens. When the lens is smaller, it captures less light, and when it is larger, it captures more light. The length of exposure is determined by the shutter speed.
Most SLR cameras use a focal plane shutter. This mechanism is very simple -- it basically consists of two "curtains" between the lens and the film. Before you take a picture, the first curtain is closed, so the film won't be exposed to light. When you take the picture, this curtain slides open. After a certain amount of time, the second curtain slides in from the other side, to stop the exposure. When you click the camera's shutter release, the first curtain slides open, exposing the film.
After a certain amount of time, the second shutter slides closed, ending the exposure. The time delay is controlled by the camera's shutter speed knob. This simple action is controlled by a complex mass of gears, switches and springs, like you might find inside a watch.
When you hit the shutter button , it releases a lever, which sets several gears in motion. You can tighten or loosen some of the springs by turning the shutter speed knob.
This adjusts the gear mechanism, increasing or decreasing the delay between the first curtain opening and the second curtain closing. When you set the knob to a very slow shutter speed, the shutter is open for a very long time.
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