Photography Camera, Lenses, and Gear 4 — Questions and Answers
Question 1: What is 'focus breathing' in a camera lens?
- The pulsing noise a lens motor makes during autofocus
- The change in a lens's angle of view as focus distance changes (Correct answer)
- The technique of breathing to stabilize the camera during focus
- The micro-vibration caused by lens element movement
Correct answer: The change in a lens's angle of view as focus distance changes
Focus breathing is the change in focal length (and thus field of view) that occurs as a lens is focused from infinity to its minimum focus distance.
Question 2: What does a higher 'stops' rating indicate for a neutral density filter?
- More light is transmitted through the filter
- Less light is transmitted, requiring longer exposure (Correct answer)
- The filter blocks only certain color wavelengths
- The filter is thicker and adds more diffraction
Correct answer: Less light is transmitted, requiring longer exposure
Each additional stop of ND filter halves the amount of light reaching the sensor, requiring a proportionally longer shutter speed for correct exposure.
Question 3: In a camera's autofocus system, what is 'phase detection' AF known for?
- Providing the most accurate focus in low light
- Being faster than contrast detection, especially for moving subjects (Correct answer)
- Requiring less battery power than other AF systems
- Working exclusively with prime lenses
Correct answer: Being faster than contrast detection, especially for moving subjects
Phase detection AF determines focus error direction and magnitude simultaneously, making it significantly faster and better suited for tracking moving subjects than contrast detection.
Question 4: What advantage does a mirrorless camera body have over a DSLR in terms of flange focal distance?
- Longer flange distance allows more lens designs to be used natively
- Shorter flange distance enables adapting nearly any legacy lens with an adapter (Correct answer)
- Equal flange distance ensures full compatibility with all lenses
- Flange distance does not affect lens compatibility
Correct answer: Shorter flange distance enables adapting nearly any legacy lens with an adapter
Mirrorless cameras have a shorter flange focal distance (the gap between lens mount and sensor), making it possible to use adapters to mount almost any legacy lens from various systems.
Question 5: What is a 'diffraction limit' in photography?
- The maximum resolution a lens can resolve based on its focal length
- The point at which stopping down further reduces sharpness due to light wave diffraction (Correct answer)
- The lens coating that limits internal reflections
- The maximum ISO before diffraction noise appears
Correct answer: The point at which stopping down further reduces sharpness due to light wave diffraction
Diffraction limits sharpness at very small apertures (high f-numbers) because light waves bend around the aperture blades, reducing overall image resolution.
Question 6: Which memory card format offers the fastest read and write speeds for modern high-resolution cameras?
- SD (SDHC)
- CompactFlash (CF)
- CFexpress Type B (Correct answer)
- XQD
Correct answer: CFexpress Type B
CFexpress Type B cards use the PCIe NVMe interface and offer the fastest sustained read/write speeds, essential for high-resolution video and burst RAW shooting.
Question 7: What is the purpose of a 'lens hood' on a camera lens?
- To protect the lens from rain and moisture only
- To block stray light from entering the lens and causing flare (Correct answer)
- To reduce the effective focal length of the lens
- To improve the lens's autofocus speed in bright conditions
Correct answer: To block stray light from entering the lens and causing flare
A lens hood blocks peripheral stray light from striking the front element, preventing lens flare and ghosting while also providing some physical protection.
Photography Camera, Lenses, and Gear 4
What is 'focus breathing' in a camera lens?