Practice Focal Length (4.8.12) - Photogrammetry Surveying

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9 questions

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Exercise
6 questions · about 4 min · pass mark 70%. Hints available.
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Quiz
3 questions · about 2 min · pass mark 70%. Hints available.
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6 sample questions

Question 1.
Define focal length.
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Think about how a lens focuses light.
Question 2.
What is scale in photogrammetry?
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Remember how maps can represent real distances.
3Question 3.
What does the term focal length refer to?
- Distance to the ground
- Distance from camera to focal plane
- Distance in mapping
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It's about the lens not the ground.
4Question 4.
True or False: The scale of a photograph taken in flat terrain remains constant.
- True
- False
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Think about the relationship between height and scale.
Question 5.
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.
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Use the formula for each elevation point individually.
Question 6.
Discuss how the scale variance might affect a mapping project in an urban environment with many tall buildings.
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Consider the impact of cliffs and valleys in urban settings.

5 more questions in this section. Enroll free to practise them all.