You know the infinitely long tunnel that appears when you look into two mirrors that are pointed at one another? Have you ever noticed that the tunnel becomes more and more green, the deeper you go?
YouTube personality Vsauce has a fascinating new video titled “What Color Is A Mirror?”. In it, Mr. Sauce explains that this is due to the fact that there is no such thing as a perfect mirror (i.e. a mirror that perfectly reflects 100% of light). The fact is, a typical mirror best reflects light in the 510nm range, which we perceive as green light.
Take a look at your camera, and there’s a good chance it’ll have this symbol: Φ — a small circle bisected by a long line that looks like a hieroglyph of Saturn. If you’ve always wondered what it means, today’s your lucky day: it’s called a “film plane mark” (or “focal plane mark”, depending on who you ask), and indicates exactly where the film (or sensor) plane is inside the camera body. One reason the mark is useful is that macro photographers often want to determine the exact distance between their subject and the film plane, and the mark can make this calculation much easier.
(via PhotoNotes.org via Reddit)
P.S. For a complete list of common camera symbols, check out this page on PhotoNotes.org.
You may have heard that digital cameras can be made sensitive to infrared light by removing the IR filter found inside, but did you now that something similar can be done with the human eye? People who have aphakia, or the absence of the lens on the eye, have reported the ability to see ultraviolet wavelengths. Claude Monet was one such person. Carl Zimmer writes,
Late in his life, Claude Monet developed cataracts. As his lenses degraded, they blocked parts of the visible spectrum, and the colors he perceived grew muddy. Monet’s cataracts left him struggling to paint; he complained to friends that he felt as if he saw everything in a fog. After years of failed treatments, he agreed at age 82 to have the lens of his left eye completely removed. Light could now stream through the opening unimpeded. Monet could now see familiar colors again. And he could also see colors he had never seen before. Monet began to see–and to paint–in ultraviolet.
[...] With his lens removed, Monet continued to paint. Flowers remained one of his favorite subjects. Only now the flowers were different. When most people look at water lily flowers, they appear white. After his cataract surgery, Monet’s blue-tuned pigments could grab some of the UV light bouncing off of the petals. He started to paint the flowers a whitish-blue.
The lens on a human eye ordinarily filters out UV rays, so we don’t see many of the things certain animals see. For example, the males and females of some butterfly species look identical to the human eye but very different to UV-sensitive eyes — the males sport bright patterns in order to attract the females!
Monet’s Ultraviolet Eye (via kottke.org)
Here’s your completely random photography fact of the day: Nutella lids can double as lens caps. Belgian photography enthusiast Frans Leys lost the 72mm cap to his 18-200mm Nikon lens, but found that the cap from his 220g jar of Nutella was a perfect fit. 220g isn’t the standard size sold in the US, but can be found in some shops.
Image credit: 18-200 mm Nikon VR lens cap by Frans Leys and used with permission
Have you ever wondered why newer Canon DSLR battery covers have a small rectangular hole punched into them? It’s more than just for style:
Take a look at the cover. Does it have a small cut-out a few millimetres in from one edge? This is not just decoration. It is designed so that you can tell at a glance which of your batteries are fully charged and which are not. The batteries that come with this cover have a blue stripe down one side of the back. When you remove a charged battery from the charger, you can attach the cover so that the blue is visible. When you remove a discharged battery from the camera, you can attach the cover so that the blue patch is not showing.
It’s a simple and useful tip that those of you who don’t read instruction manuals may have never learned.
(via Canon Professional Network)
Captured on April 1, 1995 by the Hubble Telescope, the photograph Pillars of Creation is one of the most famous space images ever made. Here’s a crazy fact though: did you know that the “pillars” seen in the photo were already long gone by the time the image was captured? Astronomers have concluded that the pillars — which measure up to 4 light years in length — were destroyed about 6,000 years ago by the shock wave from a supernova. Because of how long it takes light to travel across such vast distances, we can currently see the shock waves approaching the pillars but won’t actually see their destruction for another thousand years or so!
(via Wikipedia via Photographs on the Brain)
Here’s your interesting photo fact of the day: did you know that sepia toning (when B&W photos are given that distinctive warm tone) is named after the Common Cuttlefish? The scientific name of the species is Sepia officinalis, and the ink produced by the cuttlefish was used for sepia toning when the technique first emerged in the 1880s.
Sepia is a dark brown-grey color, named after the rich brown pigment derived from the ink sac of the common cuttlefish Sepia. The word sepia is the Latinized form of the Greek σηπία, sēpía, cuttlefish. [#]
Nowadays, sepia ink is generally replaced with other dyes or pigments that produce the same hue.
Photographic print toning (via Reddit)
In interviews published on Sony’s website, the company’s designers talk about how its latest DSLRs are based on a styling technique called “Tensile Skin”, in which sharp lines and curved surfaces giving a “natural sense of tension”. What’s interesting is the tool they used to explore this idea: an ordinary sock. Art director Takuya Niitsu says,
What helped me explore this idea was an ordinary sock. As soon as I stretched the sock over our structural mock-up, it transformed the jumble of blocks into a coherent, sculptural unit. It looked fresh, and the jutting edges resonated nicely with the gentle contours. Although this unified whole could be called “monoform,” it was hardly monotonous, and there was a pleasant sense of tension. I knew that following this approach would lead us to the new shape for Alpha SLRs.
Discoveries in a new approach to design (via sonyalpharumors)
Ever wonder why most DSLR cameras capture images with a 3:2 aspect ratio, while most other cameras use 4:3? It’s because they were designed to match different things:
Common aspect ratios in still photography include 4:3 (1.33) used by most digital point-and-shoot cameras, Four Thirds system cameras and medium format 645 cameras; 3:2 (1.5) used by 35 mm film, APS-C (“classic” mode) and most DSLRs;
[...] The reason for DSLR image sensors being the flatter 3:2 versus the taller point-and-shoot 4:3 is that DSLRs were designed to match the legacy 35 mm SLR film, whereas the majority of digital cameras were designed to match the predominant computer displays of the time, with VGA, SVGA, XGA and UXGA all being 4:3. [#]
Prints have been around longer than digital cameras, so that’s why your compact camera photos are cropped when you try to have them printed as standard 4×6 prints (4×6 prints have an aspect ratio of 3:2).
Aspect ratio [Wikipedia]
Image credit: Aspect Ratio by schani
Here’s a fun entry to add to your brain’s collection of “totally random facts about the world”: Nikon’s 52mm lens caps will fit neatly on most beverage cans. 52mm isn’t just a common diameter for camera lenses… it’s also an international standard diameter for can tops!
Sorry Canonites, your lens caps don’t really work for this.
Image credit: Photograph by kokotron and used with permission