Controlling the Photographic Process

With today’s modern digital cameras you can have as much or as little control over the picture taking process as you want. You can use either the point and shoot or point and think method of picture taking. Although different cameras have different buttons and menus, they all contain variations on the basic types of controls. We are going to look at how the basic controls affect your photographs and how you can optimize their use.

All digital cameras have an Auto exposure control This control will take your picture and try to produce the best possible image based on the conditions However because of the specifications of the camera the final product my not have the best exposure.

There are two parts to taking good photographs –Composition –Exposure Composition is the creative part of the photographic process Exposure is the technical part of the photographic process

Composing Pictures Before we begin discussing the various controls that are on your camera I would like to discuss some basics of photographic composition No amount of control or editing can take the place of good picture composition. This is by no means a complete discussion of composition, just some basics.

Good composition is essential in photography. It allows you to convey messages and emotions through the images that you shoot. Composition, the act of composing the image in the viewfinder, is a visual process of organizing the elements and individual details of a scene into a balanced and pleasing arrangement.

Photographic composition is ultimately a matter of person taste. What one person likes another person may hate. We will discuss some general rules of composition that can help you take better photographs.

Some General Composition Rules - Framing Fill the entire photograph with your subject

Have a strong focal point Choose one main subject for you photograph. The main subject can be one object or several. Do not include distractions that pull people away from your photo.

Rule of Thirds Divide you viewfinder into thirds both horizontally and vertically Place your subject along the divide lines between the equal areas or at the places where the these lines meet

Leading Lines Leading lines help to lead the viewers eye to the important object in the photograph Be careful using leading lines so they do not lead away form the important part of the photograph

Angle of View Sometimes you will get a more interesting photograph by changing you angle of view.

Perspective Sometime it will make a photograph more interesting if you add an object to convey the perspective of the photo.

Balance The correct combination of colors, shapes, and areas of light and dark that complement one another

Creative Camera Controls The mode dials of some digital cameras have auto and what I will call creative and exposure settings. Creative Exposure Auto

Creative Controls Auto – The camera selects all of the settings Portrait – blurs the background and makes the person stand out Landscape – focuses as much of the foreground and background as possible.

Sports – captures fast moving object, sometimes will include a burst mode. Night – allows you to capture your subject against a dark background. The flash goes off to capture the subject and the a long shutter speed is used to fill in the background. You should use this mode with a tripod.

SCN – provides a number of specific scenes which allows the camera to set the most appropriate setting. Some of the SCN setting are; –Foliage –Beach –Snow –Fireworks –Indoor –Night snapshot

Exposure Control To control exposure for the best possible picture under a give condition To create a special exposure effect, such as creating a silhouette To use a specific shutter speed to create a certain look, like blurring the flow of a stream To isolate subjects by using selective focus. To create a special color effect by changing the white balance.

Exposure Exposure is the amount of light that strikes the sensor (CCD) It is determined by –The intensity of the light (sensitivity of the sensor ISO) –Amount of light admitted by the iris of the lens (f-stop) –Length of time the light strikes the sensor (shutter speed)

Metering The exposure meter is the component that determines the best combination of f-stop and shutter speed to produce a quality picture based on the ISO setting for the sensor.

Common types of exposure modes –Averaging –Center-weighted –Spot Other types –Corner-weighted –Top or bottom-weighted –Matrix metering

Averaging – the exposure meter figures the exposure based on the average of all of the light striking the sensor. –Works best where you have a good mixture of light and dark throughout the picture

Center-weighted – the exposure meter emphasizes a zone in the center of the frame to calculate the exposure –Based on the idea that the most important element in the picture is located in the center of the frame –Examples of center-weighed pictures Portraits Architectural

Spot-metering – confines the light reading to a limited area. –Allows you to select a specific spot in a picture to determine the metering.

In digital cameras the shutter button has two positions –Partly depress will set the auto focus and the exposure. –Fully depressing the button will take the picture.

The sensor (CCD) needs a minimum amount of light to be activated (normal exposure) CCD Sensitivity ISO

To little light (under exposure) creates a dark image CCD Sensitivity ISO

Too much light (over exposure) creates a light image. CCD Sensitivity ISO

In ether case detail will be lost in the created image. CCD Sensitivity ISO

Software can try to recreate the missing information but it is not as good as a well exposed original.

The sensitivity setting of the sensor (CCD) determines how much light is need to activate the sensors on the CCD Sensitivity is set by ISO setting or film speed. The larger the ISO number the more sensitive the CCD is. Increasing the ISO number will allow you to take pictures in lower light situations but will introduce additional noise or in photo terms grain to the picture.

Different ISO Settings ISO 100ISO 800

Controls how much light is allowed though the lens The measurement term is f-stop There is a formula to determine f-stop numbers Lens Opening F-stop

The important things to remember about f- stop numbers are: –The smaller the number the less light reaches the CCD –That f2 allow twice and much light to reach the senor as f4 Wide angle mode of a lens has a lower f- stop number the a telephoto mode of the same lens

In photography there is a term depth of field Depth of field means how much of the picture is in focus from front to back The f-stop setting effects the depth of field. The higher the f-stop number the more that will be in focus from front to back. The f-stop is controlled in the Av mode Why Play with F-stops

Depth of Field Example F 10F 3

A control that allows you to manually change the f-stop setting incrementally Usually allows you to vary the f-stop by +/- 2 (f8 can be changed to f10 or f6) Can not go below the minimum f-stop of the camera lens. Use this for small changes rather then the Av function on the camera. Exposure Compensation

Controls the time the CCD uses to capture the image Shutter speed is measured in seconds and fractions of seconds Obviously the shorter the shutter speed the less light captured by the CCD Shutter Speed

Shutter speed is used to create photos with motion effects including –Stop action –Blurring The shutter speed is controlled in the Tv mode.

Stop Action Example 1/2501/60

Blur Example 1/301/9