Types of Vision

Question 1

Mesopic vision:

Answer 1

• Transition zone between photopic and scotopic.
• Experienced at dawn, dusk, and under full moonlight.
• Includes brightness output from NVG.
• Most dangerous visual condition for crewmembers.

Question 2

Scotopic vision:

Answer 2

• Night vision.
• Partial moonlight and starlight conditions.
• Acuity degraded to silhouette recognition (20/200 or less).
• Cones are ineffective.
• Poor resolution in detail and color perception is lost.
• Off center viewing (scanning).

Question 3

Photopic vision:

Answer 3

• Daylight or bright light.
• Central vision.
• Color sense and image sharpness
• Visual acuity 20/20