Photo I: Aperture, Shutter Speed & ISO · (aperture and shutter speed) •Have built-in light...

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Transcript of Photo I: Aperture, Shutter Speed & ISO · (aperture and shutter speed) •Have built-in light...

Photo I: Aperture, Shutter Speed & ISO Week 1 Lecture

Techniques

-What is a DSLR Camera?

-Film vs. Digital Sensor

-Exposure Modes and Functions

-Exposure Triangle

-ISO

-White Balance

Composition

-Light, intensity and direction at different times of the day

DSLR Cameras

• What does SLR mean?

• Many current DSLRs also have live view mode (uses direct feed from sensor)

Terminology – Front View

Menu Set Up

• Color Space

• Quality

Your New Best Friend...

The camera manual! Printed or PDF format

Film Versus Digital Capture

35mm Roll Film

After entire roll is exposed it has to be developed to create this type of negative below.

How an Image is Created on Film

Silver crystal halides reacts to

light and forms a negative

After the film is developed the negative is used to print on photo paper.

Digital Camera Sensor

Captures picture elements and send the information

to the camera memory card.

Little electronic pulses pick up picture elements to form an image

Height X Width = mega pixel

Film vs. Digital Cameras - What has changed?

• Capture - Instead of cameras capturing images by film digital cameras use a recyclable sensor that captures an image and then sends it to be stored in on a memory card.

• Additional Features – ISO and white balance options can be adjusted in-camera and for each image. Auto focusing options has also advanced in digital camera technology.

Similarities - Film and Digital Cameras

• Same ways to control light

(aperture and shutter speed) • Have built-in light meters

• Have many of the same features like exposure mode options, flash and focus options.

*Capture media has changed but the fundamental camera features have not.

Exposure Modes and Functions

Exposure Triangle

ISO and Digital Photography

Program Exposure Mode

• The camera decides on exposure indication through aperture and shutter speed combination.

• Photographer still can choose options such as ISO, white balance, flash use and in some cases, file quality and type.

ISO -International Standard Organization

What does ISO control on a digital camera?

• Regulates the sensitivity of the camera sensor

• Guides the in-camera light meter to decide on exposure

• Relates to film photography ISO ratings

The Purpose of ISO Ratings

• The camera’s light meter need a baseline of how sensitive the camera sensor will be in order to judge the light and provide exposure indication.

• Setting your ISO at a low rating such as 80 or 100 will make the sensor less sensitive to light thus your exposure will half to be longer.

• Low ISO is ideal when there is plenty of light and/or your subject is still.

The Purpose of ISO Ratings cont. • The higher the ISO rating the more sensitive the camera

sensor becomes to light.

• Most current digital cameras have at an ISO range of 100 – 6400 or faster.

• Slow versus fast ISO – image quality is better with low ISO speeds so always choose the lowest possible ISO.

• Fast ISO and other variables contribute to digital noise (RGB specks and grain in the darker areas of an image)

When should you raise the ISO ? • When you see unwanted motion blur in your playback view

• When an exposure requires a shutter speed at 1/60th of a second or below and you don’t have a tripod.

• When you are trying to capture moving subjects in low light

• Turn Auto ISO off!

Examples of different ISO speeds in the same

*These images

were taken in

Program mode,

camera on tripod

Note the

exposures stay

relatively the

same but as we

look at the

details the image

quality is

compromised

Details of low versus high ISO

Low ISO provided better clarity and color

High ISO has digital noise/grain in the darker areas and the color is not as vibrant

White Balance

White Balance

• Films were either balanced for daylight or Tungsten lighting

• Digital camera sensors have been designed to compensate for color casts used basic color theory.

• The sensor combines Red, Green and Blue.

• For example if you choose Tungsten WB option the camera will add blue to the grid to counteract the orange/red color cast.

White Balance Options Icons

Color Casts and Lighting Types

White Balance Options under Tungsten Lighting

Most accurate WB choice was Tungsten

Least accurate WB choice was Flash

Light Affects of Time of Day, Year and Weather

Week 1 Assignments

Techniques

• ISO Experiment

• White Balance Experiment

*Remember all techniques assignments are opportunities to create engaging compositions!