Talk:Flashlight

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External links[edit]

I removed external links that served no purpose other than advertising discussion forums. ParasiticToxin (talk) 07:38, 28 July 2009 (UTC)


Incandescent lumens[edit]

This article was written by a kindergarten class. —Preceding unsigned comment added by 216.19.29.109 (talk) 23:07, 26 February 2011 (UTC)

I tagged the 10,000 lumens statement as dubious, because I find it incredibly hard to believe that any flashlight produces that many lumens. For comparison, a standard 100 W household bulb produces around 1700 lumens. So scaling linearly (yes, I know incandescents increase in efficiency as power goes up, but this effect is not dramatic) we would expect said "flashlight" to be 588 W or so. I just don't see any handheld device putting out that sort of power, especially one that is battery-operated.Ngchen (talk) 04:01, 10 March 2008 (UTC)

The article explains it is a halogen bulb instead of normal incandescents, a maximum of 38 lumens per watt can be achieved as per the halogen lamp article. That puts the power to around 260W which less than your estimates but still way too high for portable use. --antilivedT | C | G 09:44, 10 March 2008 (UTC)
Tag was needed, reworded to fix, added ref. Most powerful incan. flashlight is probably the "The Torch" from Wicked Lasers, about 4,100 lumens using a 50w halogen bulb: [1].
That's still 82 Lm/W - still way above what a filament bulb is capable of. 109.153.242.10 (talk) 16:15, 25 January 2012 (UTC)
The company Web site says 100 watt bulb - how's 41 lumens/watt sound? A little more plausible, especially if you don't care how long the lamp lasts. (And it doesnt' say how many watts they actually use). The reference for Incandescent light bulb says that tungsten at its melting point can theoretically produce around 52 lumens per watt and that the best a blackbody radiator can do is 95 lumens per watt. Halogen doesn't change those fundamentals. --Wtshymanski (talk) 17:13, 25 January 2012 (UTC)
I can accept that. Back in the good old days of non halogen photoflood bulbs, a 275 W bulb produced the equivalent light of around 8 x 100 W (UK) light bulbs. Around 36-37 lm/W. Quite impressive. But the bulb had an average life of just 2 hours!. 109.153.242.10 (talk) 18:24, 25 January 2012 (UTC)
Custom-made flashlights with more than 10,000 lumens exist. This one is based on a 600W halogen lamp. Runtime with one battery charge: 5-10 minutes. "The Torch" may be the brightest commercial flashlight around. By the way, it uses a 100W bulb, there is no halogen bulb with more than 50 lm/W anyway. I'm not even aware of any bulb rated at 41 lm/W, so it's probably overdriven. Aragorn2 (talk) 20:31, 8 November 2009 (UTC)

Cowan or Hubert?[edit]

This Web page http://www.ideafinder.com/history/inventions/flashlight.htm says the Cowan story is not the case. Research needed - I wonder if the 1947 New Yorker is available at my local library 'fiche collection.... --Wtshymanski (talk) 16:57, 25 September 2008 (UTC)

Intrinsic safety[edit]

Could we get a reference for a flashlight that is "intrinsically safe"? I'm not a hazardous areas expert but from what I've read an "intrinsically safe" device is one that has such low stored energy in it that it cannot ignite a flammable atmosphere. This is different from "non-incendive" or so-called "explosion-proof" devices that are designed either so that sparks and hot spots can't form, or so that any sparks that happen can't set off an explosion outside the device. You can, for example, get an explosion-proof motor starter but it has a heavy cover and deep threaded joints to prevent flames from escaping the enclosure when the contacts break a circuit. It's non-incendive and explosion-proof, but not intrinsically safe. Hmm, the article Intrinsic safety isn't too reassuring either, or maybe IS is more inclusive than I think. --Wtshymanski (talk) 04:58, 21 August 2011 (UTC)

It appears they do call them "intrinsically safe". --Wtshymanski (talk) 20:27, 22 September 2011 (UTC)

Oh, dear... another US-specific article![edit]

At the risk of probably flogging a long-dead argument, elsewhere in the world we use torches - things that illuminate continuously, and that don't flash. Blitterbug 22:10, 23 December 2011 (UTC)

Speak for yourself. A couple of my flashlights send Morse code (by flashing). --Wtshymanski (talk) 00:44, 24 December 2011 (UTC)
He has a point, only the Americans use 'flashlights'. Our hand held torches flash just as well (when equipped with a suitable button). 109.153.242.10 (talk) 18:27, 25 January 2012 (UTC)


I agree.America is the only place where flashlight is the preferred term where as torch is used in the UK,Ireland and the rest of the english speaking worldEggilicious (talk) 23:50, 21 March 2012 (UTC)

Even Agatha Christie knew what a flashlight was. [[2]]. --Wtshymanski (talk) 15:44, 22 March 2012 (UTC)
... and I (here in northern England) didn't know that they were called "torches" until I met people from further south. We still call them flashlights. Dbfirs 14:22, 23 July 2013 (UTC)
To clarify linguistic differences: what many of us call a 'flashlight' was first marketed as an 'electric hand torch' (hence 'torch'); the term 'flashlight' was coined because the battery contacts were very weak and caused early designs to flash on and off randomly. Frednotbob (talk) 19:58, 13 February 2016 (UTC)

C class[edit]

What our tagger didn't mention is the criteria that make this C class and what's missing to improve it. The criteria read:

The article is substantial, but is still missing important content or contains a lot of irrelevant material. The article should have references to reliable sources, but may still have significant issues or require substantial cleanup.

...

The article is better developed in style, structure and quality than Start-Class, but fails one or more of the criteria for B-Class. It may have some gaps or missing elements; need editing for clarity, balance or flow; or contain policy violations such as bias or original research. Articles on fictional topics are likely to be marked as C-Class if they are written from an in-universe perspective.

Specific guidance would be more useful than a generic tag. What's missing? What's biassed? What's original research? What are the vague "issues" that displeased the god-like eye? --Wtshymanski (talk) 23:53, 30 December 2011 (UTC) Here's what the gods have decreed for B-class

The article meets the six B-Class criteria:

The article is suitably referenced, with inline citations where necessary. It has reliable sources, and any important or controversial material which is likely to be challenged is cited. The use of either <ref> tags or citation templates such as {{cite web}} is not required. The article reasonably covers the topic, and does not contain obvious omissions or inaccuracies. It contains a large proportion of the material necessary for an A-Class article, although some sections may need expansion, and some less important topics may be missing. The article has a defined structure. Content should be organized into groups of related material, including a lead section and all the sections that can reasonably be included in an article of its kind. The article is reasonably well-written. The prose contains no major grammatical errors and flows sensibly, but it certainly need not be "brilliant". The Manual of Style need not be followed rigorously. The article contains supporting materials where appropriate. Illustrations are encouraged, though not required. Diagrams and an infobox etc. should be included where they are relevant and useful to the content. The article presents its content in an appropriately understandable way. It is written with as broad an audience in mind as possible. Although Wikipedia is more than just a general encyclopedia, the article should not assume unnecessary technical background and technical terms should be explained or avoided where possible.

Any help here? --Wtshymanski (talk) 23:57, 30 December 2011 (UTC)

Suggest merge[edit]

Suggest merge the non-redundant contents from Solar powered flashlight here; it's a minor variation in flashlight construction. --Wtshymanski (talk) 16:52, 2 January 2012 (UTC)

  • Oppose - This article is already plenty long, and merging more information will just make it longer, and hence, more difficult to read and find information. Plus, Solar powered flashlight is a reasonable content fork of sorts, and is an established, comprehensive and well-referenced article. Northamerica1000(talk) 13:58, 10 January 2012 (UTC)
  • Oppose - The article has enough content and significant notability to keep as it is. Suraj T 03:48, 11 January 2012 (UTC)
Comment by nominator - There's very little non-redundant content at Solar powered flashlight - there's a definition (which is already here), a few platitudes about general features of flashlights, and about 3 lines particular to solar flashlights. It's not going to break anybody's browser if it's included here, and shouldn't an encyclopedia article be comprehensive? --Wtshymanski (talk) 04:39, 11 January 2012 (UTC)
After a minor tweak to clarify what could be misunderstood to be general features of flashlights, all of the content refers specifically to solar flashlights and not general features of flashlights.Suraj T 05:53, 11 January 2012 (UTC)

Lumens for tasks[edit]

I'd like to find a good reference for how many lumens is useful for various tasks:

  • Less than 1 lumen - supplement to night-adapted vision, avoiding bumping into furniture or stepping on cat
  • 2-3 lumens - finding a keyhole, walking around a room with dark-adapted vision, close reading or close work
  • 20-30 lumens - general household flashlight purposes, walking good trails (2 D cell incandescents at lower end of this range)
  • 100-200 lumens - Tactical flashlights, suitable to identify a man-size target at firearms range (one lumen per yard is what I've read), but without too much backscatter
  • 100 or more - Outdoor, long range uses; search and rescue; inspection lights, caving
  • 500-1000 - Orienteering, running unfamiliar trails at night
  • 100-1000 - Bicycle headlights, brighter lights in urban areas

Ranges overlap considerably and personal taste dictates - but it would be useful to turn the abstract notion of "lumens" into ranges that the reader could relate to his own experience. I've found some advertising sites and at least one blog, but I'm really looking for better references. Not finding too many scholarly papers yet, some on miner's lamps and flashlight use in Kenya...but the Web is very wide. --Wtshymanski (talk) 14:58, 20 January 2012 (UTC)

That'd be useful. Good luck.   Will Beback  talk  17:31, 20 January 2012 (UTC)
Someone doesn't understand what lumens are. A 1000 lm bicycle lamp will be a very bright light source indeed. (Lumen is the measure of the total perceived light output of a light source integrated isotropically). A bicycle lamp light source will be less than 5 lm. Focussing the beam in a particular direction doesn't change the lumen output of the source. 109.153.242.10 (talk) 18:33, 25 January 2012 (UTC)
Yes, yes it would be a very bright lamp. 5 lumens doesn't cut it in the bike world any more. These folks [3] claim 1400 lumens for their bike light. We've come a long way from the PR2 bulb and 2 D cells. (A North American low-beam auto headlamp is somewhere around 1600 lumens.) --Wtshymanski (talk) 19:28, 25 January 2012 (UTC)
...and it is going to be even harder to find sources that match candelas to tasks! --Wtshymanski (talk) 19:37, 25 January 2012 (UTC)

──────────────────────────────────────────────────────────────────────────────────────────────────── IEC hasn't gotten around to writing the definitive standard for flashlight lumens for tasks, so the table with the vague and general categories is as good as its going to get for now; at least it has a published source. Once can't refer to the megabytes of stuff ont eh flashlght enthusiasts forums, which would generally agree with the rough and ready groupings in the table. --Wtshymanski (talk) 21:54, 29 November 2012 (UTC)

Teaching grade school science is harder than it used to be[edit]

When I was a boy and the world was new, one unit of grade-school science classes was to teach about electricity by unscrewing the flashlight and showing the battery, bulb, and switch; maybe a little lecture on the reflector, too. A modern flashlight would be better suited to teaching a 3rd year EE course, with converters, pulse-width modulation, microprocessor controls, etc. (If someone has written about it, it might be a useful comment to make in the article - a flashlight may not be the simple model electrical system of years gone by.) It gets worse...we were taught pennies don't stick to a magnet but nickels do, and you can make electricity by stacking "copper" pennies and silver dimes. The first time I saw a bronze-coated steel penny cling to a magnet, a little part of my childhood died....--Wtshymanski (talk) 14:56, 24 January 2012 (UTC)

Nostalgia is not what it used to be ... In what way does this contribution seek to improve the article? - DieSwartzPunkt (talk) 16:55, 26 January 2012 (UTC)
A flashlight was the canonical simple system used to illustrate basic electrical concepts. Modern flashlights may not be a good vehicle for demonstrating these concepts. If someone has run across literature that describes that as a problem in teaching, it might be worth adding that observation to the article. --Wtshymanski (talk) 17:30, 26 January 2012 (UTC)
Agreed. I think this is overcomplicating the topic. Cantaloupe2 (talk) 01:09, 28 November 2012 (UTC)

Beam visibility[edit]

ANSI FL1 used 0.25 lux illuminance, based on a full moon. But we can easily see a magnitude 0 object, it attracts attention in the night sky. The moon is mag -12.5 or so, which makes it (2.51^12.5) about 99,000 times more illuminance than starlight; and the square root of 99,000 is 314. So, you can see a flashlight several hundred times further than the FL 1 0.25 lux "working distance" states; which is why optimistic flashlight vendors prefer to write things like "Projects a beam visible for over a mile!" instead of giving the ANSI working distance of, say, 20 feet. But I need a citation for this....--Wtshymanski (talk) 21:27, 14 February 2012 (UTC)

America only standards. Find ISO something. Cantaloupe2 (talk) 01:05, 28 November 2012 (UTC)

DIY and Mod'ing of Flashlights[edit]

I am thinking this is a worthy topic for its own section.

There are multiple well visited forums where all people do is trade stories on how they upgraded their torches (flashlights). I would think it is a very strong hobby that deserves some mention. There must be a way to add this information without it turning into an advertisement for those forums, yes? — Preceding unsigned comment added by MarcoPolo419 (talkcontribs) 09:47, 20 April 2012 (UTC)

Gallery[edit]

Each of those types of flashlight is mentioned in the text, and its probably better to collect the pictures in one place than have them competing with text for screen space. --Wtshymanski (talk) 20:53, 27 November 2012 (UTC)

Another editor commented that policy discourages galleries. I agree too. This is not a collage of historical flashlights. We simply don't need that many pictures. Cantaloupe2 (talk) 01:04, 28 November 2012 (UTC)
You don't think there's encyclopedic value in showing the reader what a diver's light looks like, what a headlamp looks like, what an inspection light looks like, what a penlight looks like? Why should we conceal this from the reader? --Wtshymanski (talk) 01:49, 28 November 2012 (UTC)
Isn't the point of Wikipedia:Galleries#Image_galleries to describe a gallery such as this one? --Wtshymanski (talk) 01:51, 28 November 2012 (UTC)
Wikipedia policy does not totally disallow galleries of images. They are permitted where they are appropriate. There are times when they are wholly inappropriate and this is one of those ocassions. Wikipedia policy discourages the use of galleries of images that illustrate different types of item that are otherwise relevant to the article. The policy is to encourage the image being moved to a section of article describing the item in question. For example: the gallery includes 'one type of diver's light' even though a diver's light receives a mention in the main body of the article. The illustration could therefore, usefully be moved to that section of the artcle. In fact, the subject of five out of the six gallery images receives a mention in the text of the article and each image should be moved to the relevant section. The remaining image, the non-incendive flashlight, receives no mention and thus either suitable text added to support the image (to which it can be moved) or the image deleted as it does not illustrate any point in the article. The logical extension to having some relevant illustrations in the gallery at the end would be to move every illustration in the article to that gallery, but that would be obviously absurd as any illustration is much more useful near the text that describes it. I B Wright (talk) 12:33, 28 November 2012 (UTC)
I have now moved the gallery images into the appropriate parts of the article so that each illustration is near to the text that describes it, a much better arrangement. I did not understand Wtshymanski's first point above. I or anybody else had not suggested removing the images, and the tag certainly did not say this. I B Wright (talk) 13:02, 11 December 2012 (UTC)
You don't think the text is rather "winding" around these images? It's somewhat a matter of taste; we can recall books in which the "color plates" were separate pages, perhaps a long way from the text. The non-incendive flashlight is also called "explosion proof" and is referenced in the text. --Wtshymanski (talk) 15:11, 11 December 2012 (UTC)
An ever present problem when there are a large number of images on the subject. Mr Wright has done surprisingly well I think, particularly as he has kept the text in the 'Formats and specialized designs' section in one column (as it has, not unsurprisingly, the most number of images).
My only (minor) observation is the use of breaks to put the 'Power sources' section separate from the images. He has assumed that everone is using the same screen size as he is. I'm sure there is a Wiki command to do the job properly, but I don't know what it is. Can anyone hepl here?
I don't understand your comment on colour plates being separate pages in older books. Actually it wasn't colour specifically but all half-tone renderings of photographs. This was not to keep the pictures separate from the text, but because half-tone printing at the time required a much higher grade of paper than was used for the text and line drawings. DieSwartzPunkt (talk) 16:29, 11 December 2012 (UTC)
Incidentally, if you have a valid critisism of something that has been missed, then it is better to say so here rather than put it in the edit summary where it can easily be missed (as indeed I had done until I accidentally spotted it nearly an hour later). Why didn't you just restore the missing alt text if it's so important? DieSwartzPunkt (talk) 16:59, 11 December 2012 (UTC)

Vandals[edit]

Some vandal has apparently gone through and changed most instances of the word "flashlight" to "fleshlight." This should definitely be fixed. 68.235.179.47 (talk) 04:18, 6 March 2015 (UTC)

It was fixed about four minutes after your warning (thank you for that), and the vandal (96.42.220.214) was warned. Dbfirs 18:31, 6 March 2015 (UTC)

Torch[edit]

Torch is very widespread use, and is not limited to the Commonwealth. ONE example is Ireland. — Preceding unsigned comment added by 171.99.189.241 (talk) 13:29, 20 June 2015 (UTC)

Agreed. Nor is "flashlight" limited to America. Dbfirs 15:56, 20 June 2015 (UTC)
And Ireland is a part of the british isles. Irish can be prime minister of the UK. Part of Ireland is in the UK (that last one I don't actually believe, honestly, the country should be the primary topic of Ireland, not the island...but that's another story for another day).. ~~ipuser 94.14.212.141 (talk) 08:12, 30 June 2015 (UTC)
What are you going on about? Dbfirs 05:56, 1 July 2015 (UTC)
Ignore him. He's a semi-literate, deluded agenda pusher — Preceding unsigned comment added by 171.99.189.241 (talk) 13:07, 15 July 2015 (UTC)

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