Talk:Rangefinder

How to handle this article
I've stubbed out this article with little more than a dictionary definition. It had been a redirect to power system automation but that seems inappropriate because it's too specific. I would redirect it to telemetry directly, but there is some suggestion that the name "telemeter" can refer to a distance-measuring device (like a theodolite, I guess) such as at Telemeter Glacier. Make of it what you will; I'm a little too confused to fix it all. Morrand (talk) 03:46, 1 December 2008 (UTC)

The original meaning of telemeter, and still one of the main uses of the word, was a device used to measure distances to remote objects (1) Yes, a telemeter is an optical rangefinder used often in the past for artillery, or in viewfinder cameras: "split-image telemeter", "inverted image telemeter", "double image telemeter" are of type "coincidence telemeter". Another optical type using binocular vision is the "stereoscopic telemeter". A simple optical method is stadiametric rangefinding. More generally, a telemeter is a device used to remotely measure any quantity. (2) That sounds reasonable, as "tele" = distant and "to meter" = to measure may not only mean measuring the distance (1) but also measuring distantly (2). But you can't say here that (1) is the definition of telemeter in a narrow sense, and (2) is the definition in a broad sense. If there is a "more general" definition there is also a less general, more specific definition. In this case, both definitions have to be related, and the general term (2) has to comprise the more specific term (1). This is not the case here, as there are tow different technical areas: (1) is rangefinding and (2) is operating a sensor and remotely receiving its data. Thus, the telemetry domain is not more general, but the term has been used in this field more recently, whereas the rangefinding use for telemeter is 200 (coincidence telemeter) or 100 (stereoscopic telemeter) years old. --Gunnar (talk) 15:05, 27 August 2019 (UTC)

Footnote
A pay television system by the name Telemeter was used in the United States from 1951 to 1965. See at. Morrand (talk) 03:46, 1 December 2008 (UTC)

Telemeter is a rangefinder
Isn't it obvious? Fgnievinski (talk) 19:26, 29 October 2013 (UTC)
 * No, it is not obvious, oppose merge. As the article used to say in the lede before you deleted the passage "More generally, a telemeter is a device used to remotely measure any quantity".  This passage was sourced and was a proper summary of the contents of the article.  Please justify the deletion.  Spinning  Spark  19:32, 30 October 2013 (UTC)
 * Support merge This article is principally about telemeters in the sense of rangefinders.  The discussions about telemetry really don't fit with the rest of the article.  I recommend merging most of the article's content into Rangefinder with a few remnants (mainly dealing with history and etymology) going into the article on Telemetry. --SteveMcCluskey (talk) 20:16, 7 September 2014 (UTC)


 * Oppose. All rangefinders are telemeters but not all telemeters are rangefinders.  Dger (talk) 22:41, 17 March 2015 (UTC)


 * Oppose and close. Chiswick Chap (talk) 14:44, 22 January 2016 (UTC)

Telemeter and rangefinder (again)
"I don't understand your point that rangefinding is not a subset of telemetry." Telemetry is a rather new sport about measuring and transmitting the data to a hub. Rangefinding as an older discipline about measuring distances. These are two different things, which are not related to each other. So, there is no general and more specific interpretation of what a telemeter could be (Btw, before reading this article I never heard that a telemetry device is called telemeter, but we should never stop learning). There are just two different interpretations of the noun "telemeter", and one is older (rangefinder) and the other one is newer (remote measurements), but it is not that one is a wider sense and the other is a narrow sense: rangefinding is measuring distances, and telemetry is measuring anything somewhere in a remote location and transmitting the measured data to a central data hub. --Gunnar (talk) 15:19, 27 August 2019 (UTC)
 * This refers to my revert earlier today. I reverted you mostly because the English was so poor it was almost meaningless.  There is nothing in the definition of telemetry that says the sensor has to be at the remote point being measured.  Only that the measurement is done remotely.  If you accept that, then clearly telemeter as a rangefinder fits the definition.  If you don't accept that and still think it is something different, then the correct thing to do is start a discussion proposing a split.  But note that we have already had that discussion once above.  The entirely wrong thing to do is to argue in the article itself that these are two different things; Wikipedia articles should be about one thing only.
 * By the way, characterising this as a "recent" usage is stretching it. The terms "telemetry" and "telemeter" have been in use in electrical engineering for well over a century (see this patent from 1893 for instance) and the practice of telemetry for things other than rangefinding for a lot longer than that. SpinningSpark 16:31, 27 August 2019 (UTC)
 * A telemeter (rangefinder) and telemeter (remote sensor) and telemeter (manufacturer) and telemeter (TV) are different things, whereas optical telemeters can be classified in stadiametric, coincidence, and stereoscopic. The coincidence telemeters have subgroups split-image, inverted image, and double image. A device for marine research that measures temperature, pressure, and salt content which transmits the data via radio to receiving station is something different. It cannot be grouped hierachically in the same basket as the rangefinder devices (see set theory). Same is true for a telemeter which we call today smart meter, which is an electronic measurement device for electricity (or gas or water) coupled with a communication device. So no, it makes no sense to me saying that a telemeter (rangefinder) is a subset of telemeter (remote sensor). The purpose of a rangefinder is to determine the distance from here to somewhere, the remote sensor in telemetry may measure any characteristic we find useful. There may be a few items which fit into the "both" category, but there is no specific and more general meaning.
 * Yes, there may be an old (original) meaning and a newer one, e.g. the article itself says the the first optical rangefinders were desinged in the late 18th century, whereas electricity came a century later e.g. for telegraphs and stuff. I have no problem in just listing 3 types of telemeters: 1a) rangefinder, 1b) chronograph scale 2) remote sensor in one article as even the article Homonym explains in different paragraphs Homographs, Homophones, Heteronyms, Polysemes, Capitonyms. But even if this is not wanted, I believe it is not much work to draft a disambiguation page, and to split the content in 1a)+1b) rangefinder and 2) remote sensor. --Gunnar (talk) 21:05, 27 August 2019 (UTC)

Telemeter as remote measuring instrument
"Examples of these are James Watt's (1736-1819) additions to his steam engines of the mercury pressure gauge and the fly-ball governor." - I don't understand this sentence. Why is a fly-ball governer a remote sensor? Why is a mercury pressure gauge a remote sensor? The principle of telemetry is that you can place the point of mesurement and the point of display anywhere you want, isn't it? Is the lookout at the top of sailing ship's mast also a telemeter as he shouts down if he sees land or another ship? --Gunnar (talk) 12:10, 28 August 2019 (UTC)
 * The Kopp source gives exactly these two specific examples and then says:
 * "These early devices monitored and controlled the inhospitable internal processes of a steam engine from a distance, albeit a short one. This was telemetry in its crude beginning."

- Brian Kopp


 * He doesn't say why he considers the fly-ball governor (and why on earth is that a redlink!) a telemeter when, on the face of it, it is telecontrol, not telemetry. But thinking about it, the governor must first sense and measure the pressure before it can take corrective action.  Kopp also discusses later commercial products replacing Watt's original instruments, the Bourdon tube and Westinghouse's hydraulic servo pressure control, immediately before the above quote. SpinningSpark 14:02, 28 August 2019 (UTC)
 * Sorry, but again I don't understand why a fly-ball governor is a remote sensor which measures "inhospitable internal processes". It is used for closed loop control and measures the rotational speed of the main shaft which usually sticks out of the machine in order to drive some useful machinery. The closed loop is done by first measuring the speed and second by acting on the steam valve via some arrangement of levers. I would not call this system telemetry, but rather integral part of a clever piece of engineering for one big item which is the steam engine. Remote (in a near field interpretation within a factory) could be the power distribution via drive belts, so that one steam engine can power several weaving looms. And the principle of a pressure gauge is that the measuring sensor needs to be connected to the gas or liquid, that is still the same with airliners of today. My understanding of telemetry is that you are not dependant from any infrastructure, so you are flexible in the sensor's position. I would even dare to say that pressure control in rotating tires is an application case of telemetry even if the "tele" in this case means not very far away. But again, this telemeter in a tire which measures pressure is not the same as a device that measures distances. So the a) optical telemeter (rangefinder) is a complete different kind of device as a b) telemetry sensor which may measure any characteristic. The metering is different: a) estimates the tele feature (distance), b) measures anything and the tele refers to the how it is done. --Gunnar (talk) 18:04, 28 August 2019 (UTC)
 * Look Gunnar, your opinion on whether or not these things are telemeters counts for nothing. What counts is that a reliable source thinks that they are.  If you want to write something different in the article then first find a source more authoritive than Kopp that says telemetry started somewhere other than in the steam age.  Once we have sources to look at we can talk.  Until then, this discussion is just wasting space. SpinningSpark 20:36, 28 August 2019 (UTC)
 * I think it is a bad habit to quote references which obviously make no sense. Even Einstein published a paper on quantum physics which was proven wrong later. Following your approach, I could strongly rewrite Wikipedia articels dealing with this research are and say that this is all bullshit, because there is this source from a famous man and two able colleague (who simply made a mistake which is perfectly human). I do rather recommend to put the state of the art (or science & technology - which evolves over time) in the article, and then add some supporting documents as references. --Gunnar (talk) 18:03, 29 August 2019 (UTC)
 * The difference there is that there are plenty of sources saying Einstein was wrong and it is easily shown that his ideas on quantum mechanics are now fringe at best. Whole books have been written on the subject.  So no, you can't rewrite quantum mechanics to say Einstein was right. SpinningSpark 20:13, 29 August 2019 (UTC)
 * It is not about if Einstein (or others) is wrong or right, it is about citing stuff regardless what the common sense and the state of science of technology tells us. --Gunnar (talk) 13:53, 30 August 2019 (UTC)
 * But it is about sources, and you don't have any. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 21:10, 31 August 2019 (UTC)
 * It is not about sources, it is about the formal procedure of chosing references and misusing sources, sometimes also called selection bias. --Gunnar (talk) 18:39, 7 September 2019 (UTC)

I just checked the other souce on the claim that telemetry was already invented in the steam age, e.g. by Watt: (Kirby 1990), p 167-169. In these three pages the steam engine of Watt is discribed, but nowhere is written that it can be interpreted as the first steps of telemetry. --Gunnar (talk) 12:31, 31 August 2019 (UTC)
 * Agreed that it does not support Kopp's claim, but it does support the claim that Watt invented the two examples and describes what they do. It is therefore a useful ref to leave in the article.  I also don't understand why you have moved the Kopp cite to not include the examples sentence.  Kopp definitely has them in the text. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 12:51, 31 August 2019 (UTC)
 * As Kirby does not say anything about Kopp's main claim about telemetry in the late 1700s, the reference should be removed. The fact that Watt's steam machine had an closed loop control for speed and a pressure gauge is quite known in many sources and not specific for the telemetry notion. Adding Kirby here does give a false impression that the main message is also supported by him. --Gunnar (talk) 18:35, 7 September 2019 (UTC)

Selligue coined the term
The question to me is: Is the telemeter Selligue (from Switzerland) the same as Alexander François Selligue who died in Paris more than 20 years later after the improved telemeter invention. See Talk:Alexander_Selligue --Gunnar (talk) 12:36, 31 August 2019 (UTC)

Ngram Analysis
Let's have a look how often the terms "telemeter" and "telemetry" have been used according to the Google Book DB: The timeframe up to WWII shows that the word "telemetry" was rather seldom use, and "telemeter" prevailed. After the Second World War, the use of "telemetry" declassified the term "telemeter" and had a distinctive peak in the 1960s. The use of "Telemeter" declined further on. Comparing "telemeter" with "rangefinder", these two words show the same range of frequencies, but while the telemeter had his peak in the 50s and 60s, the rangefinder took over in the 70s and 80s and went down later. --Gunnar (talk) 14:09, 31 August 2019 (UTC)

Article move
I don't especially object to the move to Rangefinding telemeter, but I do strongly object to the removal of large chunks of content that do not fit with the new title. There was not the slightest attempt to merge any of that material into the new redirect to Telemetry. That article does not even contain the term telemeter making the redirect something of an Easter egg. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 12:51, 21 September 2020 (UTC)


 * Telemeter was a WP:CHIMERA: two unrelated or marginally related concepts sharing the name name. The word "telemeter" was and still is mentioned and defined in Telemetry. And the portions deleted from Telemeter were mostly already stated in Telemetry, esp. in History, reason why a merge was unnecessary. I'm puzzled what it's that you like in the previous state of the articles? fgnievinski (talk) 16:15, 21 September 2020 (UTC)


 * As I said, I'm not objecting to this in principle, but this article includes Kopp's take on the steam age. It discussed Seebeck, Siemens, Davy and Kelvin, none of whom are even mentioned in the telemetry article.  Morse code is mentioned, but the relation of Morse's equipment to telemetry is not.  The Insitution of Civil engineers discussion of terminology and the hijacking of the term by electrical engineering is not discussed.  Strain gauges in rocketry.  Bio telemetry of astronauts.  So no, I don't agree that it was "mostly already stated in Telemetry."  Rather, it was a thoughtless purge of material without doing the hard work of ensuring that WP:PRESERVE was maintained. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 17:04, 21 September 2020 (UTC)


 * I've now segregated the discarded portion in Telemeter. I've tagged it as original research, because nowhere in the main reference on telemetry I can find the words "rangefinder", "rangefinding", or "surveying" (Brian Kopp, "Industrial telemetry", in Telemetry Systems Engineering, ). fgnievinski (talk) 20:44, 21 September 2020 (UTC)
 * What?? That doesn't make any sense. Kopp's book is not about rangefinding, so why would you expect to find it there?  Nor is Kopp used to cite anything about rangefinding.  So claiming original research on that basis is just nonsense. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 06:52, 23 September 2020 (UTC)
 * there are two types of telemeters: rangefinding or not. It seems original synthesis to state that rangefinding telemeters inspired the development of non-rangefinding telemeters, just because the former existed before the latter. It might just have been a case of two independent developments sharing a common name (the prefix "tele" was in vogue at that time). The first citation (Kopp) only discusses non-rangefinding telemeters, the second one is a patent registration (a primary source), and the third source is the only one that acknowledges there was a competition for the common name between the two concepts (in a much milder tone than the Wikipedia article implied). Still, nowhere we have sources stating that non-rangefinding telemeters grew out of rangefinding telemeters. This article is in desperate need of disambiguation, hence my renaming to "rangefinding telemeter". Could you please reconsider the renaming in itself? fgnievinski (talk) 15:41, 23 September 2020 (UTC)


 * BTW, the history of this article talk page shows how problematic the conflation of two concepts has been over the years. fgnievinski (talk) 20:47, 21 September 2020 (UTC)
 * I agree that this has been problematic. I would support splitting the rangefinder material into a separate telemeter article.  I'm saying split off the rangefinder material because the current page has been about telemetry devices from its creation.  The rangefinder page can still take the primary title (I would support that too) but the history should stay with the telemetry meaning even if it is moved to a new title. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 07:21, 23 September 2020 (UTC)
 * Agreed overall; just to confirm: would you agree with merging the history of non-rangefinding telemeter to Telemetry? fgnievinski (talk) 15:41, 23 September 2020 (UTC)
 * That wasn't my suggestion at all. But I'll accept it as a compromise, providing that the merge is done with some sympathy for the target article and not just dumped in.  Specifically;
 * that all information is preserved in some form,
 * the primary title carries a disambiguating hatnote, and
 * that it is clarified where necessary that the term telemeter is being discussed (such as at the discussion of EEs hijacking the term)
 * <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 16:16, 23 September 2020 (UTC)
 * OK, I gave it a try; how do you you like it? can I leave the renaming for you? Thanks. fgnievinski (talk) 06:10, 24 September 2020 (UTC)
 * I don't know what you mean by renaming. What needs renaming?  What does need doing is checking the incoming links and retarget any that are no longer relevant.  As the person who has repurposed the page, I think it is down to you to do that. <b style="background:#FAFAD2;color:#C08000">Spinning</b><b style="color:#4840A0">Spark</b> 15:01, 24 September 2020 (UTC)
 * I didn't want to undo your undoing of my renaming, but now it's fixed. fgnievinski (talk) 21:04, 24 September 2020 (UTC)

The change to the article title violates WP:Title as "rangefinding telemeter" is not a common name for a rangefinder. In fact, I've never heard of the former term despite using rangefinders extensively during my army career. Nor was it used by my few naval references from the 1930s–1950s, much less anything more recent. Perhaps the term was used by surveyors or such types, but it's not in common use in any military or naval context within the last 90 years, which is likely the majority of such instruments in use during that time. Please be so kind as to restore the article to its original title.--Sturmvogel 66 (talk) 12:50, 6 April 2022 (UTC)
 * I agree.--Srleffler (talk) 04:49, 10 April 2022 (UTC)
 * Telemeter is a very uncommon term for rangefinder. A telemeter is typically a remote indicator dial in the English Language.Damwiki1 (talk) 23:32, 3 June 2022 (UTC)

Requested move 10 April 2022
<div class="boilerplate" style="background-color: #efe; margin: 1em 0 0 0; padding: 0 10px 0 10px; border: 1px dotted #aaa;">
 * The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this section. 

Rangefinding telemeter → Rangefinder – This article started out at Telemeter, but that created ambiguity with other uses of that term. The ambiguity was resolved by moving the article to the current title, but that does not satisfy WP:COMMONNAME. "Telemeter" and "rangefinder" both appear to be common names for this type of device, but "rangefinding telemeter" is not. The article should have been moved to Rangefinder. Srleffler (talk) 04:49, 10 April 2022 (UTC) — Relisting. Colonestarrice (talk) 08:47, 9 May 2022 (UTC) <div style="padding-left: 1.6em; font-style: italic; border-top: 1px solid #a2a9b1; margin: 0.5em 0; padding-top: 0.5em">The discussion above is closed. <b style="color: #FF0000;">Please do not modify it.</b> Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
 * Support. Clear common name. -- Necrothesp (talk) 12:46, 13 April 2022 (UTC)
 * Comment: I was about to close this request, but then I found this edit on Rangefinder. On Rangefinding telemeter, this edit is related; on Distance measurement, there may be an edit in this list related to the redirection of Rangefinder, but I can't discern which edit is related per the edit summaries. From the looks of this, it seems some sort of merge needs to be reverted to make the new title accurately encapsulate the scope of the article since some of what is currently at Rangefinding telemeter is duplicated/hiding in the edit history of Rangefinder. Steel1943  (talk) 00:05, 19 April 2022 (UTC)
 * Oppose the primary topic of rangefinder, should there be one, would be Rangefinder camera. Either "rangefinder" should point there, or it should be a disambiguation page -- 65.92.246.142 (talk) 04:31, 27 April 2022 (UTC)
 * That's not the most common use of the term. It should be a hatnote to the main article, though.--Sturmvogel 66 (talk) 10:14, 27 April 2022 (UTC)
 * No. Rangefinder camera cannot be the primary topic. A rangefinder camera is a camera with a rangefinder built in. The latter is the primary topic. Rangefinder camera is derivative. Even if there is no primary topic, we don't make dab pages with only two entries. That's handled with hatnotes. --Srleffler (talk) 05:49, 29 April 2022 (UTC)
 * No. Though the camera has the device contained within it, it is commonly known as a "rangefinder" or "RF" in and of itself. And it is the most common usage to the widest audience. A 2DAB can be built if we find there is no primary topic per WP:NOPRIMARY. I would prefer the camera be the primary landing spot. -- 65.92.246.142 (talk) 03:47, 1 May 2022 (UTC)
 * It is commonly known as a rangefinder among camera enthousiasts and in the context of cameras, not in the world at large. Open a private window in your internet browser and try the search bar on Google, Amazon, Ebay... Hell, even B&H. You'll see it. JBchrch   talk  03:59, 1 May 2022 (UTC)
 * I don't think that the numbers of camera people familiar with that term for a type of camera outnumber those with military or naval experience.--Sturmvogel 66 (talk) 10:52, 1 May 2022 (UTC)
 * I understand that rangefinder cameras are commonly known as "rangefinders" among camera enthusiasts. That isn't sufficient to make that the primary topic. Based on a quick Google search, I would say there is a much bigger audience for rangefinders for hunting and golf than there are for rangefinder cameras.--Srleffler (talk) 21:27, 1 May 2022 (UTC)
 * Support - Rangefinder and Telemeter are technically synonymous. Either would be an appropriate title.  Rangefinder is a more natural title.  However, it is not overwhelmingly the common name.  NGRAMS show this. Testing this complicated by the fact that there are literary works with the term “Rangefinder” in the title and there are companies with “Telemeter” in their name. Mike Cline (talk) 12:16, 20 May 2022 (UTC)
 * The ngrams graph you posted appears to show that rangefinder is overwhelmingly more common in modern usage. It has been half a century since telemeter was more common.--Srleffler (talk) 17:50, 21 May 2022 (UTC)