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ABO / NCLE Prep
Opticianry certification
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Transposition
Drill
Transposition
Minus-cylinder to plus-cylinder and back.
Set up the drill
Difficulty
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Hard
Half-dioptre steps, round axes.
Questions
10
20
30
Time per question
Off
15 s
30 s
60 s
Start transposition drill
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Related lesson
Read the lens optics lesson