DEW2.1. Spatial Analysis: Length

{ Digital Earth Watch Contents } { All GSS Books } Materials AnalyzingDigitalImages software  Plant Leaf with Ruler image (or any image including an object of known size such as a ruler to determine scale). Open An Image Start the AnalyzingDigitalImages software and open a picture by clicking on one of two options: “Open Picture” in the File […]

DEW1.5. Dueling Beams of Light

{ Digital Earth Watch Contents } { All GSS Books } The computer-based color explorations allow millions of colors to be viewed efficiently, but do you really believe it? Make and mix your own beams of colored light to see what happens. Materials Two overhead projectors, or two slide projectors, or one of eachIf using […]

DEW Sources of Equipment

{ Digital Earth Watch Contents } { All GSS Books } The following sources are not endorsements of any particular product or supplier, but since one of the goals of this project is to develop and integrate low-cost equipment to support scientific exploration and learning, we did need to post our sources. Aerial Photography: Purpose–valuable way to collect useful […]

DEW1.6. Resolution and Pixel Color

{ Digital Earth Watch Contents } { All GSS Books } The number of pixels in an image tells you the picture’s resolution. More pixels means a higher resolution, allowing you to distinguish more details in the picture. The Pixels button of the software DigitalImageBasics can increase and decrease the resolution of the image, so that you […]

DEW1.2. LEDs As Light Sensors

{ Digital Earth Watch Contents } { All GSS Books } It is now possible with inexpensive technology to measure the intensity of specific wavelengths of light. Light Emitting Diodes (LEDs) were invented in the 1960s. An LED is a device in which electrical energy is converted into light in a very narrow range of […]

DEW1.4. Creating Colors

{ Digital Earth Watch Contents } { All GSS Books } Materials: Software: ColorBasics* Charts: Tri-color Creation Chart Tri-color Prediction Chart Tri-color Reference Chart *The author of ColorBasics software, John Pickle, has a website where you can find new web-based apps on his website’s Color Vision page: Detect Change in Color Detect Differences Between Colors […]

DEW3. Analyzing Plants and Ecosystems

Chapter 3 { Digital Earth Watch Contents } Plants are indicators of the quality of the local environment that impacts all living creatures in the area. Can we examine plants to be able to read their signs of an unhealthy environment and be able to identify the causes of the problems? To do that, it’s […]

DEW2. Measuring With Digital Images

Chapter 2 { Digital Earth Watch Contents } I. The Power of Digital Images With the inventions of the computer and the Internet, many of us use digital cameras or cameras in smart phones as tools to record memories by capturing images of objects. But digital images are now more than just a way to […]

DEW1. Digital Image Basics

Chapter 1 { Digital Earth Watch Contents } Of our five senses, sight provides near-instantaneous information over a large range of distances and space. So it is no coincidence that people use a plethora of images to convey a rich variety of data: photographs, maps, drawings, paintings, movies, text documents, signs, etc. With the inventions […]

Digital Earth Watch

The Digital Earth Watch (DEW) project grew from a NASA grant project titled Measuring Vegetation Health. Its goal was to teach about how monitoring the health of vegetation can be done at various scales: from individual plants to large scale ecosystems. See Overview. Contents Chapters Investigations Challenges 1. Digital Image Basics 1.1 How Is Light […]