Midterm of DOOM

Question 1

Define Remote Sensing

Answer 1

the science, technology and art of obtaining information about an object area or phenomenon without touching it.

Question 2

What is electromagnetic energy?

Answer 2

elector magnetic energy is carried by electromagnetic radiation by transmitting the oscillation of electromagnetic fields through space or matter

Question 3

4 examples of Electromagnetic energy

Answer 3

Infrared
Visible
Ultraviolet
Microwave

Question 4

Define Scattering

Answer 4

the unpredictable diffusion of radiation by particulates

Question 5

Define Absorption

Answer 5

the loss of energy to constituents

Question 6

How does the atmosphere affect spectral responses patterns?

Answer 6

The atmosphere absorbs electromagnetic energy and causes the resulting image to be dim.

Question 7

Name characteristics of an ideal remote sensing system

Answer 7

• uniform energy source
• non-interfering atmosphere
• super sensor
• unique energy matter interaction of the earths surface
• real time data processing
• multiple data users

Question 8

Name 4 types of resolutions

Answer 8

• Spectral
• Spatial
• Temporal
• Radiometric

Question 9

Describe Spectral Resolution

Answer 9

how much of the electromagnetic spectrum can the sensor differentiate between

Question 10

Describe Spatial Resolution

Answer 10

the size of the pixel projected on the ground

Question 11

Describe Temporal Resolution

Answer 11

frequency if data acquisition over an area.

Question 12

Describe Radiometric Resolution

Answer 12

the ability of the sensor to decipher between electromagnetic energy acquired (the difference between pixel values)

Question 13

What is the difference between passive and active sensors?

Answer 13

Passive sensors only receive information while active sensors send and receive

Question 14

Define Geo-stationary satellite

Answer 14

a satellite that stays over a single position of the ground

Question 15

Define sun-synchronous satellite

Answer 15

satellite stayes on the sunny side of the earth and crosses the equator at the same time every day.

Question 16

5 advantages of Aerial photography

Answer 16

• Improved vantage point
• Capability to stop action
• Permanent record
• Broadened spectral sensitivity (beyond what the eye can see)
• Increased spatial resolution

Question 17

List 3 types of film

Answer 17

Black and white
Colour Film
Colour infrared film

Question 18

List and describe 2 types of black and white film

Answer 18

Panchromatic - UV and Visible spectrum

Infrared - UV, VIS and NIR

Question 19

Describe colour film

Answer 19

layer film, each layer is sensitive to a different range of the spectrum

Question 20

What bands colour Infrared film sensitive to

Answer 20

NIR, red and green of visible spectrum

Question 21

4 types of filters used in arial photography

Answer 21

• High Pass
• Band Pass
• Interference
• Antivignetting

Question 22

3 types of Aerial cameras

Answer 22

Frame
Panoramic
Continuous strip

Question 23

What is the difference between small and large scale photographs?

Answer 23

Large scale covers a covers a small area in greater detail

Small scale covers a large area with less detail

Question 24

What is GCP

Answer 24

Ground Control points

Question 25

What are the 3 techniques to enhance an image and describe them

Answer 25

Grey level thresholding - brak the hitogram into two parts (true / false) black / white
Contrast Enhancement - Linear and Gaussian
Colour enhancement

Question 26

What is digital image processing

Answer 26

a collection of computerized techniques for the manipulation of digital images

Question 27

What are the 4 p’s in processing

Answer 27

Pre-processing
Processing and analysis
Post Processing
Presentation

Question 28

What are the steps in geometric correction using GCP’s?

Answer 28

• determine GCP’s
• Apply transformation equation
• root mean square Error
• resampling
• evaluation