Skeptics Stack Exchange
Skeptics Stack Exchange

Questions tagged [light]

for questions about claims based on, or related to, visible light.

28 questions
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Is a spotlight like the Bat-Signal possible?

In the Batman movies, Batman is called when a powerful yellow spotlight with the bat drawing is projected in Gotham City's clouds. The unique drawing then become very clearly visible in the clouds on the entire city. Is this actually possible or at…
Victor Stafusa - BozoNaCadeia
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Do LED light bulbs last as long as claimed by the manufacturers?

Manufacturers routinely claim that their LED light bulb can last from 20,000 hours to 50,000 hours: Anecdotes, such as this one suggest otherwise. Daily mail wrote: More than a quarter did not meet claims of a 15,000-hour life Disappointing…
Question Overflow
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Does the phase-out of incandescent light bulbs measurably reduce overall electrical power consumption?

Many countries are phasing out incandescent light bulbs. For example, in the European Union, various types of classic light bulbs have been removed from the market in the last years. The claim is that this process will help reduce overall electrical…
Heinzi
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Is it preferable to use a computer in a darkened room?

In his latest blog post, Jeff Atwood states: We computer geeks like it dark. Really dark. Ideally, we'd be in a cave. A cave … with an internet connection. The one thing that we can't abide is direct overhead lighting. Every time the overhead light…
Sklivvz
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Can blue light from LCD panels cause damage to the eyes?

In Japan there is quite a fad about LCD blue light filtering and how they might help reduce eyestrain, etc. The web site of a major computer accessory manufacturer has an English-language press release on iPad blue light filter with a nice graph…
Ken Y-N
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Do LED lights of any colour damage your eyes?

There is a Daily Mail article from May 2013: Do 'environmentally friendly' LED lights cause BLINDNESS? In the article, they specifically focus on blue LED lights and the wavelength of this light as being the problem and that it can damage your…
Dave Hilditch
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Do fluorescent lights cause stress?

I have heard that fluorescent lights are generally bad for you. The explanations range from the light being in the blue area of the spectrum: The signature "glow" of fluorescent lighting is created by sending an electrical charge through a special…
Beofett
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Are car headlights getting brighter?

This news story in Popular Science asks whether car headlights are getting brighter and concludes they are not: So are headlights actually getting brighter? The short answer is no—although there was a tweak to headlight regulations in 2008—but…
matt_black
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Can a lightbulb once inserted into your mouth be safely removed?

There is a viral video going around that repeats a claim I've heard before about getting a light bulb stuck in your mouth Graphic reads, The bulb shape allows it to be put into the mouth, but taking it out is problematic. Central to the claim…
Evan Carroll
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Do blue lights on railway platforms reduce suicide?

Does the installation of blue lights at specific locations on station platforms reduce the incidence of suicide... at that location? using that particular method ('suicide by train')? overall? The references below include a paper on the subject,…
A E
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Do Valkee bright light headsets reduce SAD symptoms?

This is old news in Finland by now, but I don't know if these products are well known elsewhere yet. The idea of Valkee headsets is bright light therapy with a twist—the light is channeled through the ear canal, directly to the brain. It should…
StackExchange saddens dancek
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Does switching the lights off help avoiding mosquitoes?

This Travel Stack Exchange answer states something I long considered for granted (probably because my parents told me so): if you want to avoid mosquitoes, switch off the light. Opening the window only works well if the temperature on the outside…
Glorfindel
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Are people physically sensitive to light from LEDs over other sources?

The Irish Independent details the claims of a woman saying she is sensitive to LED light, and that it causes her nausea. The article explains that neurologists, opticians and ophthalmologists found nothing medically wrong with her. That still leaves…
Mikey Mouse
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Does fluorescent lighting in schools correlate to increased illness and behavior problems?

A morning talk radio program was discussing Scotopic sensitivity syndrome and made the claim that in schools where fluorescent lighting had been replaced with indirect non-fluorescent lighting had more than 30% less absences due to illness and…
Chad
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Should I refrain from putting my clothes to dry outside on a full moon?

This website (French) explains: N'étendez jamais votre linge de couleur un soir de pleine lune. En effet, ces nuits sont plus froides que les autres et font poindre une rosée contenant du peroxyde d'hydrogène, composant qui décolore le linge. My…
nic
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