Basic Camera Techniques

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HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

The word Photography comes from the Greek word

photos

which means light and with light.

graphe

which means to draw. This basically means that Photography is drawing Photography as we know it today, where a permanent image can be captured, dates back to 1825 when the French inventor called

Joseph Nicéphore Niépce

created the black and white image to the right using a metal plate covered in a light sensitive coating. View from the Window at Le Gras, France

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

The first colour image was produced in 1861 by the Scottish physicist

James Clerk Maxwell

and was produced by projecting three images, one red, one blue and green which when combined created the image to the right. Digital photography which we use today (photography without the use of film or chemicals) dates back to the 1970’s where Steven Sasson, and engineer at Kodak, used an image sensor instead of film.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Light Photography would not be possible without light. Light is a form of electromagnetic radiation which is visible to the human eye. The study of light and how it interacts with different things is called optics and the area of optics is something which is very important to the creation of an image using a camera. Light always moves in a straight line

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES Refraction

Refraction is the bending of light when light rays pass between one transparent object (for example glass) and another (for example air or water) An example of this is shown to the right. Refraction causes the pencil to appear to be broken and not line up.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES Refraction

When light meets a transparent object it slows down as it slows it changes direction as is shown in the example below

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Refraction & Lenses

Convex lenses are used in camera lenses. These lenses take advantage of refraction and as they are curved they are able to focus light to a single point. This makes it possible for us to capture an image which is in focus.

A side effect a refracting lense like this one is that the image projected appears upside down. This is exactly the same in the human eye however our brain corrects the image so we don’t see the world upside down.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES Focal Point and Focal Length

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Path of Light Through a Camera

The camera shown here is called an SLR camera. This stands for

Single Lens Reflex

.

Single Lens

- because there is only one path of light through the camera to both the viewfinder and film.

Reflex

– because of the mirror which moves out of the way when you press the button to take a photograph. This allows the film behind it to be exposed to the light entering the camera.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Direct & Diffuse Transmission Direct transmission of light can be found when light passes through a transparent material such as glass in a thin clean window. The light passes easily through with little distortion When light passes through a translucent material such as tracing paper or white acrylic the light rays are scattered. This happens when light rays are scattered by clouds which pass in front of it.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Absorbtion of Light Light is made of a spectrum of colour and is called the RGB (Red, Green and Blue) Additive Colour Model.

White light is made up of a combination of red green and blue combined. Rainbows are a good example of this. When white light is scattered it is possible to see all the colours of the spectrum.

The absence of all light is black.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Absorbtion of Light Only light which reflects off an object can be seen. Once light is absorbed by an object it is transformed into heat and is no longer visible to the naked eye.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Reflection of Light Reflection makes vision possible. We do not see objects; we see light Because most objects produce no light, their visibility depends entirely on light reflected from them.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Reflection of Light

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Reflection

Diffuse Specular Is a mirror like reflection of light.

Is the reflection of light in many directions.

A single ray of light is reflected off a smooth shiny surface in a single direction.

This happens when a surface is rough (at a microscopic level) such as paper, plaster walls or fibre in clothing.

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Reflection

Specular

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

Reflection

Diffuse

HIGHER PHOTOGRAPHY UNIT 1: BASIC CAMERA TECHNIQUES

A white object reflects all the light (therefore reflects all the colours) and very little is transformed into heat.

A black object will absorb all the light (and therefore all the colours) and most of the energy is transformed into heat.

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