Exposure: Aperture

In Digital Photography the exposure is the most important aspect to consider by the photographer. Exposure mainly composed of three basic thing Aperture,Shutter speed, and ISO, but let us focus first in the Aperture.

Let us first understand the what is the effect of aperture in Digital Photography.

What Is... Aperture?

When you look at the technical specifications of a digital camera, one of the very first specification mentioned is its maximum aperture and/or its aperture range.

What is 'aperture,' what is a good aperture range, and how is aperture relevant when it comes to choosing a digital camera?

What Is Aperture?

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).

[Note: Many camera user manuals today will refer to the aperture in terms of "aperture value" instead of f/value. I'm not sure when this trend started but don't get confused between "aperture" and "aperture value." Aperture value" is simply another way of saying f/value.]

In practice, unless you are dealing with a fixed-aperture lens (many simple point-and-shoot cameras have only one fixed aperture), the aperture of a lens is usually expressed as a range of fstops.

When you read the specifications of a camera, the aperture may be expressed in a number of different ways, the following three being the most common:

• Maximum Aperture:

Max. Aperture

F2.8

This simply states that the maximum aperture for the lens is F2.8.

• Aperture Range:

Aperture Range

F2.8-F8.0

This states the max. and min. aperture, the assumption being that there are standard increments between them.

• Maximum Wide-Angle and Telephoto Apertures:

Aperture

F2.8-3.5 or F2.8(W)-F3.5(T)

This gives the max. aperture for the wide-angle (F2.8) and telephoto (F3.5) focal lengths of a zoom lens.

It is usually not too difficult to figure out that a stated range deals with maximum apertures and not max and min apertures: the mimimum aperture should be quite small at F8, F11, F16 or F22.

A "fast" lens is one that has a large maximum aperture (F2.4, F2.0 for current digital cameras; F1.4, F1.2 for 35mm film cameras.

Type of Camera

Types of Camera

The camera or camera obscura is the image forming device and photographic film or a electronic image sensor is the sensing medium. The respective recording medium can be the film itself, or a digital electronic or magnetic memory.

Photographers control the cameras and lens to exposure the light recording material (such as film) to the required amount of light to form a "latent image" (on film) or "raw file" (in digital cameras) which after appropriate processing, is converted to a usable image. Modern digital cameras replace film with an electronic image sensor based on light sensitive electronics such as "Charge couple devices" (CCD) or " complementary metal-oxide semiconductor" (CMOS) technology. The resulting digital image is store electronically, but can reproduce on paper or film.

You also need to choose the best camera for you, depends on your purpose. Learn digital photography in the step by step process.