The first Midterm will consist of ten short answer questions and a map interpretation section. The short answer questions can be answered with a few words, phrases, and/or sketch illustrations. They often have more than one part, so read each question carefully. The map interpretation portion will involve answering a list of questions and doing several manipulations or calculations on a single topographic map.In the Short Answer section, I will probably ask you to describe the procedure you would use to calculate, say, the ground distance between two points given the representative fraction on a map, or the various other manipulations you practiced in Lab 1, but I will not require that you do the actual calculations. You should be familiar with the formulas. In the Map Interpretation section, I will ask you to do some simple calculations. You can bring a calculator to class. Straight edges will be available.
The following topics will be included on the exam:
Map Interpretation
Map symbols --
nominal, ordinal, interval & ratio,point, line, area
contour lines, vegetation types, etc.
Map scales
large and smallgraphical, verbal, representative fraction
conversion between types
Map projections --
developable surfaceslight sources
qualities preserved -- shape, area, distance, direction
types and areas of distortion
Coordinate systems -- appropriate uses
Geographic grid systemUniversal Transverse Mercator
State Plane Coordinate System
Survey systems -- history, uses, interpretation of
Metes and boundsFrench long lot
Spanish land grants, desenos
U.S. Public Land Survey (township & range)
Topographic maps, thematic maps -- portrayal of information, uses
Interpretation of physical features, usingcontour lines -- shape, slope, aspect (how to determine)depressions, stream valleys
streams, rivers, stream gradient, stream patterns
drainage patterns
vegetation types -- forests, scrub or chaparral, riparian vegetation,
swamps or marshes, orchards, vineyards, grassland
using vegetation patterns to interpret landforms
Interpretation of cultural features
street and highway patternsrural settlement patterns
site and situation of settlements
urban development, time series studies of maps
shopping centers, industrial centers, freeways, etc.
natural resource development -- logging, mining, oil & gas, etc.
Place names -- evidence of settlement history, ethnic history
Project strategies -- how you use different maps to compile information, answer questions
Sample Questions
1. What are the three main types of map scales? Which type can be reduced or enlarged with the map without affecting its accuracy?
2. How would you calculate the scale of a map or air photo that has no scale shown, if you could use another map of known scale to compare it to? (describe steps or show formula)
3. What are the main differences between a survey system and a coordinate system? Describe an example of each.
STUDY GUIDE, SECOND MIDTERM
Tuesday, April 13 The second midterm will consist of ten short answer questions, plus five questions regarding stereo pair air photos that you will look at using the mirror stereoscopes.
Terms and Concepts
Air Photos
Electromagnetic SpectrumThree Energy LawsStefan-Boltzmann, Planck, WeinWavelengths of Visible, Ultraviolet, Infrared (near, mid, far), etc.
Absorption bands and windows
Reflected, scattered, absorbed solar radiation
Albedo
Emissivity of different materials
Spectral reflectance of different materials
Cameras, lens, diaphragm,
shutter speed, aperture, focal length, focal planeexposure time
angular field of view - inversely related to focal length
mapping cameras, fixed focus lenses, lens filters
Films--black & white, color, infrared,
structure, base, emulsion, backing, filterssensitivity (range, in terms of spectrum)
resolution, film speed
developing
appropriate uses
Air Photos --vertical, high oblique, low oblique
Fiducial marks, edge markingsAir Photo Interpretation
Recognition Elements --Shape, size, pattern, shadow, tone or color, texture, association, siteTasks for Interpreting air photos: classification, enumeration, measuring
Stereo Air Photos
requirements for stereo pairs -- overlap, vertical, etc.Planning a air photo shoot, items to consider
How stereo works -- parallax
Types of stereoscopes
Types and sources of distortion
Vertical exaggeration, related to focal length, overlap
Resolution, photo scale (uses of different)
Viewing stereopairs, reversed topography, etc.
Photogrammetry
Calculating scalePrincipal point, conjugate principal point, nadir
parallax, relief displacementmeasuring height of objects using single and stereo air photos
be familiar with equation elements (what you need to know to calculate)
We will include material on planimeters, parallax bar, etc. on next exam
SAMPLE QUESTIONS
1. Where in the spectral distribution of solar radiation does the VISIBLE spectrum fall? How does this compare with the spectrum of energy emitted by the earth?
2. What is the structure and sensitivity of color film? (Sketch a well-labeled diagram.) How is this different from color infrared film?
3. How does parallax allow a person to view two air photos in stereo? How much overlap between successive air photos is needed for 100% of the flight area to be viewed in stereo?
AIR PHOTO ANALYSIS. In the second part of the text, you will examine five sets of stereo pairs and answer questions for each. Each pair will be marked with a letter written in grease pen in the upper left corner of the first photo of the pair. Features that you are asked to identify or interpret will be marked with arrows or other delineating marks.