4.8.12 - Focal length
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Practice Questions
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Define focal length.
💡 Hint: Think about how a lens focuses light.
What is scale in photogrammetry?
💡 Hint: Remember how maps can represent real distances.
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Interactive Quizzes
Quick quizzes to reinforce your learning
What does the term focal length refer to?
💡 Hint: It's about the lens not the ground.
True or False: The scale of a photograph taken in flat terrain remains constant.
💡 Hint: Think about the relationship between height and scale.
1 more question available
Challenge Problems
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If an aerial camera with a focal length of 150mm is at 2000m, but the ground height is variable between 50m and 100m, calculate the scale at both points.
💡 Hint: Use the formula for each elevation point individually.
Discuss how the scale variance might affect a mapping project in an urban environment with many tall buildings.
💡 Hint: Consider the impact of cliffs and valleys in urban settings.
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