Top 10 photography factsPhotography quiz
Why were photographic prints sepia toned?
For improved resistance. Sepia toning enhances archival qualities of the photos. Chemicals are used to convert the metallic silver in the print to a sulfide compound, which is at least 50% more stable than silver.
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.
Who should you expect to show stronger red-eye effect?
Blue-eyed people. The iris plays no role in the effect, but the blue-eyed people have relatively low melanin in the fundus as well. Therefore, they show a much stronger red-eye effect, as the light passing fundus is not absorbed by melanin. The role of melanin in red-eye effect is nicely demonstrated in case of heterochromia (one eye blue, one brown): typically, only the blue eye displays the effect.
World's fastest high-speed cameras were built to take photos of specific objects. What kind of objects?
Nuclear bomb explosions. The rapatronic cameras are capable of recording a still image with an exposure time as brief as 10 nanoseconds (that would give 100 million frames per second if the camera was capable to do multiple pictures). The camera uses two polarizing filters mounted with their polarization angles at 90° to each other and a Faraday cell which briefly changes the polarization plane of light passing through it, acting as a shutter.
What does the word "photography" literally mean?
Drawing with light. The word photography derives from the Greek photos ("light") and graphe ("drawing"). The term was coined by Hercules Florence, a French painter and inventor, who used it in his diary to describe the process. Photos is also the root of words such as photon or photophobia (fear of light).
What photographic technique was used to create this photo?
Light painting. The photo was taken with long exposure. For the first 15 seconds, the author hold still with lights on, to achieve the light in the background. Later, he switched off the light and wrote his name with light in his hand. He used his nose as a reference point so he could close the "O" letter - which explains the flare at this position.
Which direction was the camera pointing at while taking this picture?
North. The entire celestial sphere seems to rotate slowly around the North-South axis of Earth's rotation. So the camera must have been pointed North or South, depending on the hemisphere the photo was taken at. But the brightest star in the centre must be Polaris, at the south celestial pole currently lacks a bright star to mark its position.
In which year was the earliest surviving photograph created?
C. 1826. Although Nicéphore Niépce took the first fixed, permanent photograph in 1822, it was later destroyed. The earliest surviving photograph by him is dated c. 1826 and is called 'View from the Window at Le Gras' (La cour du domaine du Gras). The image was created at Saint-Loup-de-Varennes and it captures the roof and surrounding countryside of the estate - Le Gras.
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".