Talk:Binoculars/Archive 1
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Archive 1 | Archive 2 |
Roof Prisms
How do Roof Prism Binoculars flip the image around horizontally? according to the diagram you should see an upside-down "F" but not a backwards-upside-down one. The F simply wouldn't translate that way. If you don't understand what I mean, imagine the F is a sticker that travels through the prism sticking to the walls of it at each consectutive point of reflection.
Correction
"Due to the way binoculars are made, the resulting ratio is the diameter of the final image on the oculars. For example, a 10x50 binocular produces a 5 mm image. For maximum efficiency, this image should match the diametor of the eye's pupil, which in dark environments grows to about 7mm. This ratio is also a measure of the brightness of the image. Thus, 10x50 and 8x40 binoculars have the same brightness, although the latter has a smaller image."
♥
I find this somewhat confusing; if "a 10x50 binocular produces a 5 mm image" because 50/10 = 5, wouldn't an 8x40 binocular produce a 5 mm image because 40/8 = 5? The article says that the latter would be smaller. Could someone who knows something about binoculars clear this up for me?--[[User:HamYoyo|HamYoyo|TALK]] 20:48, Jul 2, 2004 (UTC)
It was simply wrong. I fixed it. Jeff Albro
In a sense the 10x50 pair has the smaller image, since it's more magnified (narrower in field). In another sense it's the other way around - with less magnification, objects in the 8x40 pair will appear smaller (and this is probably what the original phrasing meant). Another difference is that the 8x40 pair gathers less light overall (35% less), which is precisely why the exit brightness is the same despite the wider-field, less magnified image. - toh 04:13, 2005 Mar 4 (UTC)
Extenal links
I have added an external link to my page about choosing binoculars for astronomy, **www.nightskyinfo.com/binoculars. I think it provides useful information and is more comprehensive than most articles on the net. I think the external link to "Doctor Binoculars" **binoculars.com/help/pick_binoculars_learn.php should be removed, as it contains very little information and lots of advertisements. However, I let this decision to more experienced contributors. Later edit: i have removed the "Doctor Binoculars" link. (AstroMalasorte)
I've removed most of the extenal links, since they were little more than advertising. I've restored one link to opticsplanet.com, since at least that page has some semi-decent content. Feel free to change or revert, if you disagree. --Bob Mellish 18:14, 11 November 2005 (UTC)
- I removed the Opticsplanet link since if you check the contributor’s history you will see their sole purpose in life was to add Opticsplanet links (linkspam) to as many articles as they could on 30 different occasions. They have been continually spaming other articles under different IP's names. So spammer is as spammer does. Halfblue 01:44, 2 August 2006 (UTC)
I really don't know how to edit, and don't want to touch the article myself, but there's at least one instance of "Porro" prism being changed to "Porno" which obviously doesn't look much like an accident, anyone mind fixing this so I don't have to break anything? Robinivich 17:02, 7 April 2006 (UTC)
I disagree about the comments regarding Dr. Binoculars from the Binoculars.com website. This was the only animated tutorial out there. It conveys numerous concepts in a visual manner that no other site does. I have added it back because I find it unique.
I have added an external link to my bird watching binoculars page, birdwatching-bliss.com/bird-watching-binoculars.html. It has very detailed information about birding binoculars and I have received comments from visitors thanking me for the info. I cover topics such as
Magnification Eye Relief/Eye Cups, Objective Lens Diameter, Field of View (FOV), Exit Pupil, Lens Coatings, Prism Design Weight, Close Focus, Waterproofing, Ease of Focusing and Rubber Armorine.
As i partly disagree with the removal of the external links in the manufacturer section by Danny, i added internal links to the wikipages of the various manufacturers. The real bicky 09:35, 21 March 2007 (UTC) - BinocularSearch
Title
Am I the only one who thinks the title should be changed to "Binocular"? Even though there are two sets of lenses, the instrument itself is a binocular. "Binoculars" is actually plural. It's certainly acceptable in common usage to add the "s" to the end, so maybe this is okay here, but it occurs to me that an encyclopedia article should try to be as correct as possible. It's really not an issue for me, but I'm curious to see what everyone else thinks about it. Kafziel 16:24, 8 June 2006 (UTC)
- Kafziel - Binoculars is definately the correct title. Although it may seem plural, binoculars is a noun whereas binocular is an adjective :-> Peripitus (Talk) 12:00, 9 June 2006 (UTC)
- That's not correct. "Binocular" is both an adjective and a noun. See [1] and [2]. Also, I don't know about other brands, but Bushnell never uses the word "binoculars" in their manuals. Kafziel 12:06, 9 June 2006 (UTC)
- Apologies but you appear to be correct - I've been mislead by common usage and [Wiktionary] [[3]]. My Webster Encyclopedic Dictionary confirms that (in the US) binocular was correct (in 1952). Current Australian usage seems to be uniformly binoculars. Web searching seems to show that binocular glasses is a term in common usage - Peripitus (Talk) 12:50, 9 June 2006 (UTC)
- That's not correct. "Binocular" is both an adjective and a noun. See [1] and [2]. Also, I don't know about other brands, but Bushnell never uses the word "binoculars" in their manuals. Kafziel 12:06, 9 June 2006 (UTC)
Astronomical
Hi, this whole article needs a carful revision. Too many repetitions and too focused on astronomical use, thus the obsession with large binos. Too many military images. I corrected some minor mistakes. ViM sept 4th, 2006
- I was just cleaning up some of the asto sections. It looks to me like all the astro stuff could be conglomerated under one heading "Astronomical use" or some such. It is a little spread out and confused right now. Halfblue 01:57, 18 September 2006 (UTC)
Use at sea
There seems to be a distinct bias to astronomical use. I bet most binoculars are sold for use at sea - every ship and most boats have a pair or three. Most of those seem to be 7x50. The best are nitrogen filled, and equipped with a built-in compass and a scale for judging distances. I added one sentence about sea use of 7x50.
(Side note - this is what I have learned in Europe (Denmark and Finland) - do sailors elsewhere use other kinds???)
I have heard that the Finnish ice breakers don't use 7x50, but only 5x magnification, because of the vibrations of a heavy engine. On the other hand, there seems to be historical evidence of using monocular telescopes on sailing ships with magnifications of over 30x. Even without engine vibration, those must have been hard to use. (This may be too much detail for this article, I don't know - one of my first contributions to wikipedia...)
- Heikki
- I have seen binoculars specifically made for use at sea. They were of the 5x or 6x you noted above. The other attribute they had was very large prism sets combined with eyepieces designed to give generous eye relief. They were built that way to make them usable on a ship that is pitching and rolling and ships with high vibrations like you listed. That optical combination meant that you could see through them even when they were pitching and vibrating in relationship to your eye without the image Vignetting or going dark. Information like that may be usful in this article. Maybe this article needs to be devided up with futhar headings "Astronamical Use", "Naval use" ect 69.72.93.165 21:07, 19 September 2006 (UTC)
Choosing binoculars
The section "Choosing binoculars" seems to be giving advice on Choosing binoculars which is in contradiction to WP:NOT, specifically the concept "Wikipedia articles should not include instructions or advice (legal, medical, or otherwise), suggestions, or contain "how-to"s. This includes tutorials, walk-throughs, instruction manuals, video game guides, and recipes". I may re-edit it into something else unless someone sees a good reason to keep it. There is a lot of "application" info floating in that section and in others that could be moved to a new heading "Applications". Fountains of Bryn Mawr 20:03, 16 November 2006 (UTC)
Rearranged article and cleanup
I cleaned up the article by rearranging the content and removing a lot of repetition. I moved the content from the intro and from the Choosing binoculars section that was not "Advice" into its relative sections. Other sections were also converted from "advice" into "description". Fountains of Bryn Mawr 02:52, 25 November 2006 (UTC)
The parameters section
Perhaps someone with more knowledge about this topic can improve the parameters section? It's a bit sparse in terms of explanations. The first external link[4] seems to have a great deal of info. Xiner (talk, email) 01:46, 1 January 2007 (UTC)
- I have taken a whack at this and added an explaining image. Halfblue 02:44, 7 January 2007 (UTC)
External links cleanup
I have added "Notes" section and added the http://www.europa.com/~telscope/binotele.htm link to "References" since it was used as a reference source by me. I have also added Binocular Buying Guide to references because it was used by me and posibly the editors above as a reference source. It is by title non-conforming to WP:EL since a "Featured article" would not contain "advice" but most of its content is description so may pass muster. Fountains of Bryn Mawr 13:47, 10 June 2007 (UTC)
Distance estimation
From the intro:
...the two views ... merge to produce a single perceived view with a sensation of depth, allowing distances to be estimated.
Maybe relative distances to various objects can be seen, but does the unfamiliar parallax perceived through a pair of binoculars actually let one accurately estimate the distance to an object? (of course distances can be estimated with a stadiametric reticle, but that is not what the intro is saying) —Michael Z. 2007-06-21 20:21 Z
porros versus roofs
The article makes the (unsourced) claim that, theory notwithstanding, in practice the best roof prism binocs are comparable to the best porros. Um, OK, comparable as in you can compare them, but most people who have directly compared Nikon Superior E's with the best roof prisms, from Leitz, Zeiss, Swarovski, whatever, will not agree that they are as good. I've seen good, objective testing results that backed this perception of mine up, but unfortunately, my source for binocular testing seems to have disappeared -- does anyone know a good one?
(Incidentally, I'm not biased -- I used my Swarovskis yesterday; I just wouldn't claim they're nearly as good as the Nikons.)
atakdoug (talk) 02:01, 27 December 2007 (UTC)
- I have re-edited this section with supporting references. I have moved the below un-sourced statements to talk. This stuff needs sources and the middle bit seems to be a little crystal ball-y.
- "However, as of 2005, the optical quality of the best roof-prism binoculars with up-to-date coating processes as used in Schmidt-Pechan models is comparable with the best Porro glasses, and it appears that roof prisms will dominate the market for high-quality portable binoculars in spite of their higher price.[citation needed] The major European optical manufacturers (Leica, Zeiss, Swarovski) have discontinued their Porro lines; Japanese manufacturers (Nikon, Fujinon, etc.) may follow suit."
notable binocular manufacturers?
I am moving the whole list in this section to talk until some references can be cited that these are "notable". Leaving in article any manufacturer that has its own article own article or mention in a another article... at least that is some kind of "vetting" . Names below should be re-added when a reference is found. Mr Floating IP (talk) 20:01, 22 June 2008 (UTC)
- I strongly disagree, i think the information value of a list of binocular manufacturers is as valuable as a small list of 'notable' manufacturers. Just leave it to anyone's own opinion which manufacturers are notable and which are not. Objectively proving that a manufacturer is 'notable', is difficult if not ridiculous. Furthermore, 'notability' also depends on the region people live in, e.g. a Japanese manufacturer which is 'notable' in Japan might not be notable in the US. Finally, none of the manufacturers in the current list have references to their notability.
- Therefore, i have added Swarovski and Eschenbach which are both European manufacturers with a generally known reputation for high quality optics.
- I am not going to try to prove this, but if you insist, use your time for finding references (it won't be difficult, i assure you) rather than wasting your time on undoing and removing valuable additions.
- This is a general 'illness' on Wikipedia: there are two ways to use one's time working on Wikipedia: one can just delete all added unreferenced information or one can search for references to this information to make it even more valuable... The real bicky (talk) 11:05, 17 March 2009 (UTC)
- All additions to Wikipedia must pass WP:V and WP:N and ways of referencing and establishing notability are spelled out there. It is your job as the editor adding information to "prove it" WP:BURDEN. Mr Floating IP (talk) 19:56, 19 March 2009 (UTC)
- Point taken but then the entire current list should be removed. (Actually half of wikipedia should be removed in that case... but that's another discussion.) 'Notability requires objective evidence' which is just absurd to apply to something subjective as a manufacturers reputation... how can you 'prove' a manufacturer is worth noting?? Actually, notability WP:N refers to whether or not a topic merits its own article, not to the content.
- So either we remove the word 'notable' and make a separate 'list of binoculars manufacturers' article or we remove the current list from the article. The real bicky (talk) 09:12, 23 March 2009 (UTC)
- As stated at WP:N Wikipedia's policies regarding content are covered by the other core content policies, in this case WP:V. My original reason for the cleanup was the really long list right below with no reference as to whether these are notable or just spam. The list heading is "notable binocular manufacturers" because the companies have Wikipedia articles (notable) and the articles state they manufacture binoculars, so I pared the list down to that. The other way to prove notability is to reference it. Mr Floating IP (talk) 08:24, 27 March 2009 (UTC)
Manufacturers Some notable binocular manufacturers as of 2008. Sorted in alphabetical order:
- Acuter – Spotting Scopes
- Alfred Kärcher
- Alpen (USA). Also sells OEM products manufactured by the KAMAKURA KOKI CO. LTD. of Japan.
- Apogee Electronics Corp.
- ATN
- Audubon
- Baigish (Russia)
- Barska Optics(USA)
- Bass Pro
- Bausch and Lomb
- Bilora
- Binoculars.com
- Bresser
- Bright China Industries
- Browning
- Brunton, Inc.(USA)
- BSA
- btc
- Burris / Burris Sawy Optics
- Bushnell Performance Optics(USA); Also sells OEM products manufactured by the KAMAKURA KOKI CO. LTD. of Japan.
- Byrtrek
- Canon Inc. (Japan) – I.S. series: porro variants?
- Carson Optical
- Celestron
- Chongqing Yangguang Photoelectric
- Coronado
- Delta Optical (Germany)– binoculars, riflescopes, microscopes
- Docter (the former Carl Zeiss Jena plant in Eisfeld) (Germany)Nobilem 7×50, 8×56, 10×50, 15×60: porro; Docter 7×40, 8×40, 10×40: roof prism.
- Eschenbach Optik GmbH (Germany) – Farlux, Trophy, Adventure, Sektor...: some are roof prism, some porro.
- Fujinon Co. (Japan) – FMTSX, FMTSX-2, MTSX series: porro.
- KAHLES (Austria)- – riflescopes, binoculars
- Kowa Co. (Japan) – BD series: Roof prism.
- Kronos (Russia)
- Leica GmbH (Germany) – Ultravid, Duovid, Geovid: all are roof prism.
- Leupold & Stevens, Inc.(USA). Also sells OEM products manufactured by the KAMAKURA KOKI CO. LTD. of Japan.
- Minox
- Miyauchi Co. (Japan) – specializes in oversized porro binoculars.
- Newcon Optik (Canada) – Big Eye series, Stibilized Image binoculars, 7x50 binoculars with compass. —Preceding unsigned comment added by 70.211.169.211 (talk) 17:43, 28 August 2008 (UTC)
- Nikon Co. (Japan) – High Grade series, Monarch series, RAII, Spotter series: roof prism; Prostar series, Superior E series, E series, Action EX series: porro.
- Olympus Co. (Japan) – EXWPI series: roof prism.
- Optolyth (Germany) – Royal: Roof; Alpin: porro
- Optolyth (Germany)– Royal, ViaNova: roof prism; Alpin, Alpin Classic: porro prism.
- Pentax Co. (Japan) – DCFSP/XP series: roof prism; UCF series: inverted porro; PCFV/WP/XCF series: porro.
- Russian Military Binoculars – BPOc 10x42 7x30, BKFC series.
- Sicong (from Xian Stateoptics) (China) – Navigator series: roof prism; Ares series: porro.
- Simmons Optics - devision of Bushnell (USA)
- Steiner GmbH (Germany)– Commander, Nighthunter: porro; Predator, Wildlife: roof prism.
- Swarovski Optik (Austria) – SLC, EL: roof prism; Habicht: porro prism, but to be discontinued.
- Vixen Co. (Japan) – Apex/Apex Pro: roof prism; Ultima: porro. Also sells OEM products manufactured by the Kamakura Koki Co. Ltd. of Japan.
- Vortex Optics (USA)
- Weaver (USA)
- William Optics (USA)
- WDtian (from Yunnan State optics) (China) – porro.
- Yukon Advanced Optics (Russia)
- Yunnan State optics (China) – MS series: porro.
- Zeiss GmbH(Germany) – FL, Victory, Conquest: roof prism; 7×50 BGAT/T porro, 15×60 BGA/T porro, discontinued.
- Zenith (Japan)
- Zen-Ray Optics (USA)– SUMMIT, Vista Series WP.
Wikipedia Rocks
This website is the best. It's helped me get so much info for my impossible science project. Yay! <(^_^)> Pokegeek42 (talk) 00:56, 6 March 2009 (UTC)
Binoculars
Do you know wthat is the make at —Preceding unsigned comment added by 174.131.0.86 (talk) 15:21, 17 April 2009 (UTC)
3d Communications?
RM'ed below to talk since there are no references and no indication whether this is fact, or fiction, or science fiction, or just some un-cited sources speculation. 70.211.213.188 (talk) 01:56, 20 July 2009 (UTC)
- Consumer applications may include a set of binoculars that are record enabled allowing the user to record the stereo viewing experience. A proliferation of this kind of stereo content may give rise to a modern implementation of the View-Master combined with cell phone. In police stakeout situations a group wear binocular system where team members can remotely share each others viewpoint making group decisions more cohesive.
Movie view
I've seen ONE movie where the view through binoculars was correctly represented. Can't remember the name of it. —Preceding unsigned comment added by 66.232.94.33 (talk) 07:04, 31 August 2009 (UTC)
Doesn't it just drive you Nuts to see two images, like through a pair of field glasses, in a movie when the character is obviously using binoculars? Takes any credibility away from it. But, Hollywood uses that "snake eyes" mask to represent the view... I noticed in "Duck, You Sucker", Rod Steiger uses an odd pair of binoculars--they almost looked like field glasses at first, until you look really closely. The objective lenses are very close together. Either these were roof prisms or some odd make--maybe correct vintage for 1913?70.176.118.196 (talk) 05:56, 2 March 2011 (UTC)
New Possible Link?
Hi i have just started a binoculars youtube channel and wanted to know if i could put a link at the bottom of the article? The channel is designed to educate the end userand we even offer a free email address where they can ask us questions and we put it back to the experts at the brands we work at.
—Preceding unsigned comment added by 86.179.115.168 (talk • contribs) 11:36, 20 October 2009
- Hi. It's quite an interesting video, but I don't think it's really encyclopaedic information. Have a look at WP:ELNO: I don't think it meets this guideline – what do you think? Richard New Forest (talk) 11:43, 20 October 2009 (UTC)
- Hi Richard. Thanks for your response. I understand where you are coming from but would say that the channel is fundamentally designed to educate, much like an encyclopedia. One of the brands we work with called Zeiss, are going to soon submit some content and Manchester university physic department. An external link also does not appear in the main body of the text, as it is merely a third party resource. Please let me know, thanks. —Preceding unsigned comment added by 86.176.163.170 (talk • contribs) 15:09, 21 October 2009
- What about the first item at WP:ELNO? Does the link "provide a unique resource beyond what the article would contain if it became a Featured Article"? If the answer is that it does not, then I think it fails. Also worth looking a little further up the same page, linked as WP:ELYES, which describes which external links should be included. Is there material in the video which could not be included in WP because of copyright issues or amount of detail? Also look lower down the page at WP:YOUTUBE. Richard New Forest (talk) 14:59, 21 October 2009 (UTC)
- Hi Richard, thanks again for getting back to me. Please see as follows in response to your questions - WP:ELNO, yes it does. In the fact that it is video and thus more interactive, should alone answer this rule. One of our tutorials, explains info about a dioptric adjustment ring, which is not properly covered in the article. Therefore, the tutorial will give a reader of the article a further and unique in-site into binoculars and their componants. WP:ELYES, copy right is no issue on the basis that we work with Sunagor and they actually endorse our channel, likewise with any other brand we use in our videos. However, as WP:ELYES does state, it would be a copy right infringement if the binoculars article were to publish in depth information (in the body of the text) about a brand such as sunagor as they do not have the right to do so, therefore in accordance with this rule as the channel provides accurate information, it should be an external link. WP:YOUTUBE, as above, the main issue here is copyright, which as i have already explained, is no issue in this case as we have the brand backing. In fact i would go as far to say that the channel could qualify as an official link under WP code of conduct. Please let me know your thoughts. —Preceding unsigned comment added by Fcamrass (talk • contribs) 01:08, 28 October 2009
- WP:ELNO doesn't ask whether there is material on a link not covered by the article, it asks whether there is material which the article would not include if it was at FA standard. If dioptre adjustment is relevant to the article, it ought to be in the article, not in a link, so I think the link probably does fail on this.
- However, I don't see that it makes a great deal of difference in this case. Why not put it in for the moment, and see how long it stays there? If later editors feel it's not of use, no doubt they will remove it; in the meanwhile it's not spam, and does contain some interesting material, so it's not doing a lot of harm. Richard New Forest (talk) 09:21, 28 October 2009 (UTC)
- Hi Richard, thanks for getting back to me. I have put the link up, thanks for your time. More content will go up over the next few months on the channel, including some educational videos on how binoculars are manufactured, as provided by the brands we work with. Please add anything if you have any further questions and i direct this to any other user who wants to chat. (Fcamrass (talk) 17:10, 28 October 2009 (UTC))
- rm'ed the link. It blatantly violates (WP:SPAM) since it is an ad for, and only features, Sunagor Binoculars. This material "can be integrated into the Wikipedia" without linking WP:ELYES. It fails WP:ELNO mentioned above #5 "Links to web pages that primarily exist to sell products", #11 "Links to blogs, personal web pages and most fansites" - speaker is a "recognized authority"? Fountains of Bryn Mawr (talk) 19:43, 28 October 2009 (UTC)
Alternative method of rating magnification
The Optic 1050 infomercials and websites say "up to 1000x magnification," but some websites say they are 10x50 (meaning 10x magnification, right?) No other binoculars seem to claim such high magnification, I don't understand how they are measuring it. I was hoping the article would have a line such as "Some manufacturers advertise their maginification using an alternative method, ... Can anyone explain? Habanero-tan (talk) 00:26, 31 December 2009 (UTC)
This is Snookerrobot: It's important to bear in mind that magnification can be expressed in two ways, i.e. linear magnification and area magnification. The area magnification is equal to the square of the linear magnification. So if the linear magnification is 10, for example, then the area magnification is 10 squared = 100. Astronomers always use linear magnification. With binoculars, the first of the two numbers (i.e. the number before the multiplication sign), is always the linear magnification, so a 10x50 binocular has a linear magnification of 10 but an area magnification of 100. I don't know anything about the Optic 1050 but I cannot imagine how such an instrument could possibly have a linear magnification of 1000. I therefore think it is the area magnification that is 1000, in which case the linear magnification would be the square root of 1000 = approx. 32 Hope this helps.Snookerrobot (talk) 16:09, 21 March 2010 (UTC)
Nice work
Some nice work on this page. It is very informative, well laid out and easy to read, with good illustrations (it is a bit short on external links though). The compehensive list of binocular manufacturers is useful. The article was a great help when I was trying to understand the theory when looking for a decent pair of binoculars recently. CPES (talk) 20:45, 31 December 2009 (UTC)
Optical coatings
This section seems to be redundant with the articles Optical coating and Anti-reflective coating, fails to even describe binocular coatings for at least a paragraph, and is full of jargon and convoluted easter egg links. Needs a cleanup. Fountains of Bryn Mawr (talk) 16:34, 11 January 2010 (UTC)
Did a cleanup. Still a little Jargon-y. Other editors who know something about coatings may want to try restoring left out tech links if they can explain them without jargon. Fountains of Bryn Mawr (talk) 21:58, 12 January 2010 (UTC)
Astronomical Use: Binoculars vs. Telescopes
For astronomical use binoculars have one rather obvious advantage, over telescopes, that is not discussed but probably should be for the sake of complete clarity. It is simply that a pair of binoculars, with two objectives, collects twice as much light as a telescope of the same aperture. So for example, if I had a pair of binoculars and a refracting telescope of the same aperture, and both instruments were of otherwise identical construction, with the same magnification, same diameter of exit pupil, and same percentage light loss through the instrument, then the binoculars would collect twice as much light as the telescope, and a star would appear to be twice as bright with the binoculars as with the telescope. Also, the binoculars would allow me to detect stars that were only half as bright as the faintest stars that I could detect with the telescope. I believe this is the reason why Patrick Moore always recommends good binoculars over small refracting telescopes. The only reason I haven't put this discussion straight into the main article is that I'm not absolutely certain that my rationale is valid. If there is anyone out there that can definitely verify that my rationale is valid, then perhaps they'd be good enough to put a section in the main article.Snookerrobot (talk) 15:36, 21 March 2010 (UTC)
- The problem I see there is binocular telescopes do not collect twice as much light as a single telescope because it falls on two eyeballs, your brain does not add up light. Fountains of Bryn Mawr (talk) 02:50, 26 March 2010 (UTC)
Too many images
Per WP:IUP I am moving images to talk for possible restoration to the article.
I would note these images have some problems encyclopedia wise re: the Galilean image has a useful optical diagram but adds 4 extra redundant images to the article, needs cropping. The Schmidt-Pechan is hard to read, low rez, and, as a bitmap, not the preferred format for diagrams. Maybe it would be better to create a page or category combining all of them at Wikimedia Commons per WP:LAYOUT. Fountains of Bryn Mawr (talk) 14:09, 29 April 2010 (UTC)
No history
The article is really only an empirical description of various systems of making and using binoculars, and thus lacks depth. Some material on the origin and development would be good. 24.81.25.127 (talk) 23:15, 6 June 2010 (UTC)
"List of binocular manufacturers"
The more I look into this list the more inaccurate it seems. The companies listed their are for the most part "brand names", not "manufacturers". A source like this points to companies like Tokyo Kogaku, Joi Optical, Nippon Kogaku, OTSUKA, Toyo Jitsugyo, HYROSHI, FUTABA, ITABASHI, etc as being the manufacturers. It may be better to change this list def to fit ""List of binocular brand names" and/or write a prose section on who really manufacturers binoculars. Fountains of Bryn Mawr (talk) 16:53, 29 August 2010 (UTC)
Can an explanation of 10x20 or 7x50mm be included in the Binoculars article?
Frequently when we go buy Binoculars or see some on Amazon.com, it says 10x20 or 7x50. Does 10x20 not mean 10x magnification but 2x? That number comes from 20 / 10. So 7x50 is 7x (by 50 / 7)... and 10x20 is actually 10x20mm? Are those the focal length of the eyepiece versus the object lens, so whatever they are, a division can give the real magnification power? —Preceding unsigned comment added by Winterheat (talk • contribs) 06:41, 30 August 2010 (UTC)
- The first number is the magnification, the second is the diameter of the objective lens in millimetres, which is an indication of the light gathering power and the overall size of the binoculars. This is in fact explained in the article, under Binoculars#Optical parameters. Richard New Forest (talk) 08:46, 30 August 2010 (UTC)
- Then it is kind of strange that... some Binoculars I bought before was something like 10x20... and so if I see a house and it appears 1cm tall, and when I use this "10x" magnification, I don't see a 10cm tall house. The house is at most 2cm tall. If according to that definition that I will be 10 times closer to the object, then the length should be 10 times bigger. This is because, a row of light poles appears as a straight line to the vanishing point. The one that is 200 feet away, if it looks like 1cm in the eyes, or on photo, then the one that is 100 feet away should look like 2cm tall in the eyes or on a photo. So 10 times closer will also mean it is 10 times taller in the eyes or on a photo.
- Another thing is that when it is actually making the length 10 times as large, then the spec doesn't say it is 100x, because when we consider the area of what is seen, it is in fact 100 times. Considering how the hard drives are marketed nowadays -- when the capacity is 931 Gigabytes large, it is advertised as 1TB, because their definition is 1,000,000,000,000 bytes, instead of 1024 ^ 4 bytes. So advertising it as 10x instead of 100x is quite a modest act. —Preceding unsigned comment added by Winterheat (talk • contribs) 09:10, 30 August 2010 (UTC)
- Yes, "10 times" magnification does mean the object appears ten times bigger, or as if at a tenth the distance. If this is not working with your binoculars, they are not ten times magnification, or you are not measuring correctly. Try looking at an object through the binoculars with one eye, and at it directly with the other, so the images overlap. Then by carefully moving the binoculars you can step the direct image along the magnified one and count how many times the one fits into the other.
- Yes, we could use the area not the length to define magnification, but it makes sense to use length, as this is directly related to visual acuity. So if something is magnified twice, our eyes can separate items half the distance apart.
- Please remember that this talk page is for discussing the content of the article, it is not a general discussion page about the article's subject – we're drifting a bit. Also, don't forget to sign your comments with the four tildes (~~~~). Richard New Forest (talk) 13:27, 30 August 2010 (UTC)
- Just a quick FYI although, yeah, this is not the "answer page" (but confusion on this may mean the related articles are confusing and need work since Wikipedia is supposed to explain things to a general reader)... but..... magnification is "focal length of the eyepiece divided into the focal length of the objective". i.e. a 10mm FL eyepiece and a 100mm FL objective gives you 10X magnification. It can roughly be described as making things 10x closer but it DOES NOT mean you will see things 10 times bigger. So what Winterheat is seeing is correct, it is not a size ratio. If the binocular manufacturer is doing their math right, the numbers are right. A bit more at an answer website[5]. Fountains of Bryn Mawr (talk) 02:19, 31 August 2010 (UTC)
- Well that would be very odd: why on earth should a technical magnification value not at least be approximately the number of times an image is magnified? And how is ten times closer not ten times larger? Simple geometry. The link you give also does not explain the point you make, and I don't think it is true either (I think it may in fact be trying to say that the 25% difference between 10x and 8x gives an impression of less than that to the eye – which I would agree with).
- I can't remember O-level physics too well from so long ago, but I think what you give as a definition of magnification is no more than a calculation used to find the magnification. I do certainly remember calculating magnification using the simple definition of how many times bigger an image appears.
- Because you had shaken my confidence, I went to the trouble of checking my own binoculars using the technique I described above. They are stamped as 12 x 42 binoculars, and I got as near exactly twelve times as I could measure. Richard New Forest (talk) 20:50, 2 September 2010 (UTC)
- My first experience with this was a day in a shop long ago when a doctor came in claiming his new 6x surgical binoculars were not 100% more powerful than his 3x binoculars. The head engineer had to explain to him that you can't "compare" two fields of view and derive magnification. Like I said, its explained badly in Wikipedia and needs allot of clarification. Its all explained under allot of WP:JARGON at Magnification re: the sections "Angular magnification" and "Measurement of telescope magnification". What I gave as a definition of magnification is where they get the number written on the binocular, --> Fo divided by Fe, that's all they mean. The actual size something will appear to the viewer compared to the actual object is a confluence angular size, tangents, eyepiece design, and a whole myriad of other variables. Its beyond my math but it seems easy to reference so we should look for text covering it and fix these articles. Fountains of Bryn Mawr (talk) 13:03, 8 September 2010 (UTC)
Field of view and magnification are not directly related, and perhaps this is where the confusion arises. Two pairs of binoculars with the same magnification may have very different fields of view, but the linear size of the image will be the same: a larger field of view will show more of the object, but any part of it will be the same linear size, in the same way as a larger window shows more of the view but does not make it nearer. However, the linear size of any part of a 6x image will indeed be double that of a 3x image. Incidentally, as the magnification article points out it's potentially misleading to talk of the "power" of binoculars, as optical power is not the same as magnification.
As far as I can see the Magnification article agrees exactly with what I have said in this discussion: the heading "Angular magnification" in the section Magnification#Magnification as a number (optical magnification) describes it very well. Those difficult sums are all to do with calculating the magnification from other characteristics, they do not define what magnification actually is. Richard New Forest (talk) 15:53, 8 September 2010 (UTC)
- Telescopes (binoculars) express magnification in Angular magnification Fo divided by Fe[6]. There is a difference between Angular magnification and Linear magnification (the actual size something appears)[7]. I just drew it on a piece of paper and Angular and Linear size are not the same when move something 2x, 3x, or 4x away, that where it is all falling flat. Fountains of Bryn Mawr (talk) 16:49, 8 September 2010 (UTC)
- I don't think you're drawing it right... The whole point of perspective is that something twice as far away looks half the size: this is why we get vanishing points and why perspective works in straight lines. Look along a straight fence or line of buildings and you will see converging straight lines, because the relationship between distance and apparent size is linear.
- Yes, it's angular magnification we're talking about: I realise I've been a mite confusing when I've used the phrase "linear size" (I did this because where we came in was why we measure magnification by length rather than area). I meant angular size, which is the size something appears. "Linear magnification" is not necessarily the size it appears, because virtual images can be at various (virtual) distances so may appear very different: a large image at a long virtual distance may be much smaller than a small one at a close distance. The size of a virtual image compared with the original therefore does not give you the angular magnification on its own; you need to know the distances too. However, this is all irrelevant to the discussion, which is about angular magnification not linear magnification.
- Again the link you give appears to agree with what I've been saying, though without my confusing language. Richard New Forest (talk) 17:54, 8 September 2010 (UTC)