What this lesson teaches
I can read and choose the right maps, graphs, photographs and other visual resources.
Syllabus 9173, Fieldwork, Additional Notes on Data. Students are required to be familiar with the following types of data: Maps: contour maps, choropleth maps, isoline maps, dot maps, flow-line maps, proportional symbols maps and cartograms; Graphs: pie charts, bars, histograms, scatter graphs, radar charts, triangular graphs and line graphs; Photographs: landscape photographs, aerial photographs and satellite images; Others: tables, schematic diagrams, illustrations and cartoons.
Make a guess
A photo shows dark water in a canal. Does it prove the canal is polluted?
- Yes, because photos show everything at a place.
- No, because photos are not useful evidence.
- Yes, because clean water is clear.
- No. Dark colour alone is not evidence.
Show the answer
No. Dark colour alone is not evidence.
Water can look dark from depth, shade or sediment. Describe what you see, then say what tests would be needed.
Describe what you can see first, then explain what it suggests and what extra information you would need.
A landscape photo shows ground-level detail, but things in front can hide what lies behind. An aerial photo shows layouts from above. Satellite images cover wider areas and may use processed colours, not natural ones.
Check the location, date, direction, scale and source. One image is a single moment, not a trend. Compare images only if the season, detail and conditions match. Dark water does not by itself prove pollution.
A schematic diagram or illustration picks out features to explain an idea. Arrows may show direction, not measured speed. A drainage basin diagram explains pathways, but cannot predict a real flood without data.
A cartoon expresses a viewpoint through exaggeration and symbols. Identify the issue, the visual evidence and the message. Neither a photo nor a cartoon gives a complete, neutral picture. Ask whose interests are shown or left out, and compare the message with other evidence.
- Landscape photo
- Ground-level view; foreground hides background.
- Aerial and satellite
- Views from above; wider areas, processed colours.
- Schematic
- A simplified diagram to explain an idea.
Step by step
Describe
Name specific visible features and where they are.
Interpret
Link the evidence to a process or viewpoint.
Qualify
What stops you concluding more?
Worked example: Reading a made-up cartoon
An official celebrates ten new benches, while a wheelchair user faces steps leading to them. The contrast criticises facilities that people cannot use. It is a viewpoint, not proof about a real town.
Watch out for this
A photograph shows everything that matters at a place.
The frame, angle and moment select what is shown. Other evidence is needed.
Check your understanding
Two aerial photos show different amounts of exposed riverbed. What should you check before claiming the channel changed permanently?
- Whether the second photo is sharper and more detailed.
- Dates, river flow, scale and whether the views match.
- Which photo shows more of the riverbed.
Show the answer
Dates, river flow, scale and whether the views match.
Yes. A low-flow day can expose more riverbed.