Digital CamerasA digital camera ( or

digital) is a camera that takes video or still

photographs, or both, digitally by recording

images by an electronic image sensor.

The front side of Cannon Digital Camera

The back side of Cannon Digital Camera

What Digital Cameras Do?

• Digital Cameras capture and record images of the world around us using digital technology. In other words, they store photographs not as patterns of darkness and light but as long strings of numbers. This has many advantages:

• It gives us instant photographs, allows us

to edit our pictures.

makes it easier for us to share

photographs using (mobile phones),

e-mail, and web sites.

Digital CamerasDigital cameras can do things film

cameras cannot: • Displaying images on a screen

immediately after they are recorded.

• Storing thousands of images on a single small memory device, recording video with sound, and deleting images to free storage space.

• Some can crop pictures and perform other elements.

How Ordinary Cameras Work?

• If you have an old-style camera, you'll know that it's ineffective without one fundamental piece of equipment: a film. A film is a long spool of flexible plastic coated with special chemicals that are sensitive to light. To stop light spoiling the film, it is wrapped up inside a tough, light-proof plastic cylinder—the thing you put in your camera.

How Ordinary Cameras Work?

• When you want to take a photograph with a film camera, you have to press a button.

This operates a mechanism called the shutter, which makes a hole (the aperture) open briefly at the front of the camera, allowing light to enter through the lens(a thick piece of glass or plastic mounted on the front). The light causes reactions to take place in the chemicals on the film, thus storing the picture in front of you.

How Digital Cameras Work?

Digital cameras look very much like ordinary film cameras but they work in a completely different way. When you press the button to take a photograph with a digital camera, an

aperture opens at the front of the camera and light streams in through the lens.

From this point on, however, everything is different. There is no film in a digital camera.

Instead, there is a piece of electronic equipment that captures the incoming light rays and turns

them into electrical signals. This light detector is called a charge-coupled device (CCD).

How Digital Cameras Work?

In a digital camera, exactly the

opposite happens. Light from the

thing you are photographing

zooms into the camera lens. This

incoming "picture" hits the CCD,

which breaks it up into millions of

pixels. The CCD measures the color

and brightness of each pixel and

stores it as a number.

Digital Cameras Aperture

The aperture controls the amount of light that reaches a digital camera

sensor. An aperture acts much like the pupil of an eye. It opens wider as light

decreases to let in more available light. It gets smaller when light

increases to reduce the amount of light entering the eye.

Aperture

Digital Cameras Focusing and F-stop

It helps to make the aperture size larger to allow

light through.

They allow the photographer to adjust the

aperture to the point of best definition of the

lens.

To get a sharp image of a subject at a given

distance, you must adjust the lens to the

appropriate distance from the film plane.

This adjustment is known as focusing. In

focusing a camera lens, the nearer the subject

is to the lens the further the image is formed

and to get a close image the lens must moved

away from the film plane to focus image.

F-Stop Functions

Focusing

How The Flash, Shatter, work

• Flash:-

Shutter :-

It is very difficult for a camera to capture an image without the right amount of light. If you are shooting outside in direct sunlight, it can manage with out the help of flash. A flash works by charging a tube filled with xenon gas in order to create a brief burst of light, an electrode on each end, a metal trigger plate behind the tube, and circuitry that provides the necessary voltage to create the flash.

A camera shutter works by opening and closing at a determined speed to allow a certain amount of light in

How does the light Sensor work?• A digital camera uses a sensor array of millions of tiny pixels in order to produce the

final image. When you press your camera's shutter button and the exposure begins, each of these pixels has a "photosite" which is uncovered to collect and store photons in a cavity. Once the exposure finishes, the camera closes each of these photosites, and then tries to assess how many photons fell into each. The relative quantity of photons in each cavity are then sorted into various intensity levels, whose precision is determined by bit depth (0 - 255 for an 8-bit image).

• Bit depth quantifies how many unique colors are available in an image's color palette in terms of the number of 0's and 1's, or "bits," which are used to specify each color.

Shutter Speed

In cameras with TTL (through the lens) viewfinders, the shutter release button also moves a mirror out of the way of the film and shutter curtain. It is this movement of the shutter curtain and the mirror that gives taking a picture its distinctive "click" sound.

Shutter speed is one of the most basic important controls on a camera. Shutter speed controls the amount of time that your film, or digital sensor, is exposed to light. In effect, the shutter determines what image is captured on your film. The shutter is a small plastic sheet that opens and closes to allow light onto the film or prevent light from reaching the film. The shutter is opened when you press the shutter release button on your camera to take a picture. The shutter speed determines how long the shutter remains open.

The time lapse of clicking the shutter button

How To Use Viewfinder

Most viewfinders can be adjusted to accommodate the camera. They slide away from the camera body which allows them to be tilted up. You can now operate the camera without putting yourself in an awkward and uncomfortable position.

A device on a camera that shows what will appear in the field of view of the lens; it helps the user target a subject, zoom and focus the image.

Viewfinder

What Is SLR? (Single-lens reflex camera)

It’s a camera that typically uses a semi-automatic moving mirror system that permits the photographer to see exactly what will be captured by the film or digital imaging system

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