The most difficult optics riddles A list of optics related questions that are most often answered incorrectly Photography quiz What term would photographers use to describe the quality of blurred part of the photo? Bokeh has been defined as "the way the lens renders out-of-focus points of light". It can be good or unpleasant, depending on the lens aberrations and aperture shape. The term comes from Japanese for "blur".very hard 32% diffractiondiffraction33%bokehbokeh32%outfieldoutfield19%overexposureoverexposure13%Created by: globalquiz.org. Statistics based on 5798 answers in 2 languages »photography riddles » What kind of lens was most likely used for this photo?Fixed focal length. Such shallow depth-of-field is possible with lens of large aperture size (small f-number). The large aperture is a typical feature (and advantage) of a fixed focal length lens. The photo was taken with a 50mm f/1.4 lens. hard 51% fixed focal lengthfixed focal length51%zoomzoom16%telephototelephoto10%macromacro22%Created by: Debbie Fox. Statistics based on 13384 answers in 2 languages »lens riddles » Which of the following camera lenses are typically more expensive?F/1.8. The smaller the f-number, the larger relative aperture there is, and that means more light for the exposure. Each aperture has half the light gathering area of the previous one.hard 53% f/1.8f/1.853%f/2.4f/2.48%f/2.8f/2.812%f/3.5f/3.525%Created by: karate kid. Statistics based on 9325 answers in 2 languages »technology riddles » The rainbow is violet on the inside of its arc. What color is it on the outside?Red. Visible light spans from red to violet. It is easy to remember, since wavelengths just outside the visible range are called infrared and ultraviolet.hard 55% blueblue15%greengreen9%yellowyellow19%redred55%Created by: Hà Linh Chi. Statistics based on 19020 answers in 2 languages »light riddles » What kind of photos can be made with standard zoom lens mounted in the reversed position?Macro photography may be accomplished by mounting a lens in reverse, in front of a normally mounted lens of greater focal length. This method allows most cameras to maintain the full function of electronic and mechanical communication with the normally mounted lens, for features such as open-aperture metering.average 67% panoramicpanoramic19%nightnight6%high-speedhigh-speed6%macromacro67%Created by: Shankar Kumar. Statistics based on 12764 answers in 4 languages »photography riddles » Which area is brighter?Both are the same. This is the well known checker shadow illusion, first published in 1995 by Edward H. Adelson, Professor of Vision Science at MIT. The area A appears darker because of its light surrounding. At the same time, area B, surrounded with dark areas, appear lighter.easy 71% AA8%BB12%Both are the sameBoth are the same71%It depends on the order of seeingIt depends on the order of seeing6%Created by: globalquiz.org. Statistics based on 19181 answers in 4 languages »illusions riddles » What kind of camera lens is that?Macro. Small front lens elements are typical for macro lenses.easy 71% macromacro71%telephototelephoto14%ultravioletultraviolet6%underwaterunderwater7%Created by: globalquiz.org. Statistics based on 18335 answers in 2 languages »technology riddles » Why do cats have vertical pupils?To better see in the dark. The sharpest image is produced by round pupils, and if cats weren’t nocturnal, they probably would have round pupils like us. But the vertical pupil, in combination with horizontal eyelids, gives the cat greater and more accurate control in different types of lighting. A cat may adjust the amount of light by moving eyelids only.easy 78% to have sharper visionto have sharper vision17%to better see in the darkto better see in the dark78%to be more attractiveto be more attractive1%it is a useless mutationit is a useless mutation3%Created by: globalquiz.org. Statistics based on 23921 answers in 2 languages »eyes riddles » Play photography quiz and see all the questions.