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Optical Illusions and Visual Phenomena

Optical Illusions and Visual Phenomena
Op­ti­cal il­lu­sion are fas­ci­nat­ing while teach­ing us about our vi­sual per­cep­tion, and lim­its thereof. My em­pha­sis here is on the beauty of per­cep­tual phe­nom­ena, on in­ter­ac­tive ex­per­i­ments, and ex­pla­na­tion of the vi­sual mech­a­nisms in­volved – to the de­gree that they are un­der­stood Be­friend­ing mo­bile de­vices: >50 in­ter­ac­tive demos now with­out Flash, but re­quire up-to-date browser ver­sions. Don’t let it irk you if you don’t see all the phe­nom­ena de­scribed. For many il­lu­sions, there is a per­cent­age of peo­ple with per­fectly nor­mal vi­sion who just don’t see it, often for rea­sons cur­rently un­known. If you are not a vi­sion sci­en­tist, you might find my ex­pla­na­tion at­tempts too high­brow.

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Hue Optical Illusion Arjen Goldschmidt has sent in what appears to be the best (proof-endorsed) color optical illusion I have seen up to date! Below examples showcase embedded lines of seemingly different colors. The reason they look different is because our brain judges the color of an object by comparing it to surrounding colors. So without us even knowing it, in first example, our brains compare the flowing red stripes to the yellow stripes, forcing us to think they are orange. The blue stripes make the red ones appear much darker -almost purple, even though they are exactly the same color! This is just one of the examples why you cannot trust what you see even with your own eyes.

Laser is produced by a living cell 13 June 2011Last updated at 01:42 By Jason Palmer Science and technology reporter, BBC News The single-cell lasers were less than 20 millionths of a metre across A single living cell has been coaxed into producing laser light, researchers report in Nature Photonics. Aleph Null: Color Music Jim Andrews: concept, programming, design Jan Odvárko: color-picker Thanks to Regina Célia Pinto, David Jhave Johnston, Ted Warnell, Maarten van Emden, Christine Wilks of JSArt, and the British and Irish Poets List--especially David Bircumshaw--for feedback during dev. Aleph Null is my first piece with the new HTML 5 canvas tag which requires no plugins and works in all modern browsers, including mobile phones. It's exciting to have such a canvas to work/play with in a public technology that is not at the mercy of a corporation's business plan or its continued existence.

Cognitive bias Some cognitive biases are presumably adaptive. Cognitive biases may lead to more effective actions in a given context.[7] Furthermore, cognitive biases enable faster decisions when timeliness is more valuable than accuracy, as illustrated in heuristics.[8] Other cognitive biases are a "by-product" of human processing limitations,[9] resulting from a lack of appropriate mental mechanisms (bounded rationality), or simply from a limited capacity for information processing.[10][11] A continually evolving list of cognitive biases has been identified over the last six decades of research on human judgment and decision-making in cognitive science, social psychology, and behavioral economics. Kahneman and Tversky (1996) argue that cognitive biases have efficient practical implications for areas including clinical judgment, entrepreneurship, finance, and management.[12][13] Overview[edit]

Chaîne de ScienceMagazine Science & Reason on Facebook: Star Size Comparison: The biggest/largest known stars in the Universe. ---Please subscribe to Science & Reason:• VY Canis Majoris (VY CMa) is a red hypergiant star located in the constellation Canis Major. Lilac chaser Stare at the center cross for at least 30 seconds to experience the three phenomena of the illusion A gap running around the circle of lilac discs;A green disc running around the circle of lilac discs in place of the gap;The green disc running around on the grey background, with the lilac discs having disappeared in sequence. The chaser effect results from the phi phenomenon illusion, combined with an afterimage effect in which an opposite, complementary, colour—green—appears when each lilac spot disappears (if the discs were blue, one would see yellow), and Troxler's fading of the lilac discs. History[edit] The illusion was created by Jeremy Hinton some time before 2005.

PMVS2 Introduction New! Please refer to our new software Clustering Views for Multi-view Stereo (CMVS). CMVS contains PMVS2 and have additional useful features (e.g., no need to worry about memory limitation any more.) PMVS is a multi-view stereo software that takes a set of images and camera parameters, then reconstructs 3D structure of an object or a scene visible in the images. Rectangle World – HTML5 Canvas and JavaScript: Tutorials and Experiments Making the Paper Snowflake Web App, Part 1 – Layering canvases Published on December 31, 2013 My first blog post explaining some of the code behind my Paper Snowflake web app. In this installment, we look at how multiple canvases are used together to handle drawing and interactivity tasks. Read more… SourceWatch Koch Spy Agency Led by Voter Fraud Huckster The Kochs have been complaining about a "lack of civility in politics" as they seek to boost their public image--but one of their top operatives helped propel perhaps the most egregious case of race-baiting voter fraud hucksterism in recent years. At the same time that the Kochs have been on a PR blitz, publicly spinning an image of themselves as well-intentioned patriots trying to make the world a better place and decrying "character assassination," they've been quietly ramping up a clandestine surveillance and intelligence gathering operation focused on their perceived political enemies, Ken Vogel reports at Politico. At the helm of this "competitive intelligence" operation is a man named Mike Roman, Vice President of Research for Kochs' Freedom Partners and who was paid $265,000 last year, according to Freedom Partners' recent tax filing. Read the rest of this item here.

Kowloon Walled City History[edit] Military outpost[edit] Lung Tsun Stone Bridge and Lung Tsun Pavilion (Pavilion for Greeting Officials) of Kowloon Walled City in 1898. The history of the Walled City can be traced back to the Song Dynasty (960–1279), when an outpost was set up to manage the trade of salt. Little took place for hundreds of years afterward, although 30 guards were stationed there in 1668.[1] A small coastal fort was established around 1810.[2] In 1842, during Qing Emperor Daoguang's reign, Hong Kong Island was ceded to Britain by the Treaty of Nanjing. LEGO Optical Illusion Mosaic This is what you get when you combine LEGO and optical illusions. Main effect – the circle made of the studs, produces the appearance of curved pieces. However, the design can appear very different depending on the angle it’s viewed from. I’m still discovering surprising patterns in it. If you still got some LEGO brick laying around, try and reproduce some of your favourite old school illusions and we’ll certainly make them pubic public!

Hand Held Light Meter - Luminous Color Meter For LEDs - HCT-99D Light Measurement Tool Easily Measure LED and Standard Light Sources Luminous Color & Illuminance (Lux) LightGigahertz-Optik's compact hand-held HCT-99D light and color meter provides fast, accurate incident color and illuminance (lux) light measurements of LEDs and standard type light sources in field service, production or research applications at an affordable price. Easy To Use, Ergonomically DesignedThe ergonomically designed HCT-99D meter is simple to use. To measure, just connect the detector and switch on the meter. The HCT-99D's high contrast 4-line backlit LCD conveniently provides a simultaneous read-out of:

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