Talk:Coincidence rangefinder

Coincidence is not Stereoscopic
These are two different types of rangefinders and the redirect for stereoscopic to here needs to be removed, please. 97.94.189.111 (talk) 12:46, 20 December 2009 (UTC)


 * That's awkward to do. While I recognise the validity your point, the best fix is to write an article on stereoscopic rangefinders. As that's obviously too much work to do immediately, how about writing one para, with a heading of stereoscopic rangefinders, ideally at least one reference, and pointing out the difference. That's pragmatically simple, not inaccurate (as the present situation) and doesn't create a dead-end (as simply deleting the redirect would). Andy Dingley (talk) 13:00, 20 December 2009 (UTC)


 * I took the stereoscopic stuff and moved it to stereoscopic rangefinder. Both rangefinders are optical instrument and look similar, but they use different principles. Therefore, two articles are needed. --Gunnar (talk) 19:11, 27 August 2019 (UTC)

Block quote
My change was reverted with the comment that the block quote added valuable information to the article. While there's no hard and fast rule on how long a quotation might be, WP:QUOTE does provide some guidance on the subject, in particular "Long quotations crowd the actual article and remove attention from other information. Many direct quotations can be minimized in length by providing an appropriate context in the surrounding text."

I don't find the following sentences to add valuable information to the article: Whatever your feelings about the quote, there can be no value in including its internal reference numbers, such as: "... the Fire Control Division of NDRC (20)." &mdash; BillC talk 23:58, 21 December 2015 (UTC)
 * American crews were being trained at Fort Monroe to operate the coincidence instruments but this plan was dropped when six British seamen, who were experienced range takers, were made available for the tests.
 * Until recently the British Services had tended strongly to the coincidence type of instrument while the American Services had adopted the stereoscopic principle for long-base instruments at least.
 * The decisions of both the British and American Services apparently grow out of different interpretations of the experience of the Battle of Jutland in World War I and are of no concern in this place.
 * Bad weather conditions and various experimental difficulties and mishaps made it impossible to obtain a really satisfactory quantity of data before the tests hall to be terminated.
 * In these latter courses continuous and broken contact were used at different times.
 * The American MI has a base length of 4.5 yards and used 12 power; FQ 25 with a 6 yard base used 28 power and UB 7, a portable instrument, has 25 power and 3-yard base.
 * The coincidence instruments did not use internal adjusters but were calibrated on targets of known range.
 * In UOE,[5] the FQ 25 had comparatively poor precision, while the UB 7, for three of the five aerial courses, had very small precision errors.
 * The number of aerial courses was too small to yield much information about consistency of observations from one course to the next.
 * For the naval target courses, one American instrument was not operating.
 * Precision errors of the other three instruments were similar to those on aerial height courses.
 * In UOE the FQ 25 was worse and the UB 7 was better than the American M1.
 * Consistency error of the UB 7 was smaller than that of the M1, even when measured in reciprocal range units, while the FQ 25 was similar in consistency to the Ml, again in reciprocals units.
 * Consistency errors of the four instruments over the 9-day period were the same when measured in reciprocal-range units.
 * Again the UB 7 was better than the stereoscopic instruments in UOE and the FQ 25 was worse.
 * This report is attached, as supporting data, to a Report to the Services issued by the Fire Control Division of NDRC (20).


 * This quote has been part of the article for 6 years. It provides a summary of a series of tests that pitted stereo and coincidence RFs against each other. The question of which is better has been a hotly debated issue between historians, since WW1, therefore context and detail are critical. Since the quote is in the public domain but not available online, it is important to reproduce it in it's entirety since it addresses a sensitive technical topic. The quote may seem long, but that's only because this is a short article The quote is already a succinct summary of a series of tests. The fact that the testing was conducted by the fire control division of the NDRC is an important detail to military historians as is the other information given. I see no reason to alter it in any way. Damwiki1 (talk) 06:28, 22 December 2015 (UTC)


 * I concur that the quote is far too long. I'm not a stupid person, but with no background in the subject, I can barely even understand it, and I'm doubtful that the average reader can either. If the quote isn't available online and is public domain, then perhaps it should be posted to Wikidata instead of here. - BilCat (talk) 14:40, 27 August 2016 (UTC)

There's lots of technical articles on wikipedia that "the average reader" will struggle with. I don't make it a habit of trying to change something that I admit I don't understand. If there are things you don't understand point them out and I will add clarification in an additional section or via footnotes. As I've explained previously the quoted section deals with a very controversial topic in naval history and needs to be reproduced in it's entirety. Damwiki1 (talk) 17:33, 27 August 2016 (UTC)

Most pictures show a stereoscopic rangefinder
https://en.wikipedia.org/wiki/File:Coincidence_rangefinder,_Overloon.jpg

shows an US Bausch and Lomb 13.5 Ft. Heightfinder M2.

This is a stereoscopic rangefinder

https://en.wikipedia.org/wiki/File:Coincidence_range_finder,_Musee_Royale_de_l%27Armee_et_d%27Histoire_Militaire.JPG

shows a German Carl Zeiss Jena Entfernungsmesser, model: Em 4m R40.

This is a Stereoscopic rangefinder

https://en.wikipedia.org/wiki/File:11-27-30_-_90mm_Height_finder_at_new_4th_Btry_position.jpg

shows an US Bausch and Lomb 13.5 Ft. Heightfinder M1.

This is a stereoscopic rangefinder Radarshadow (talk) 13:24, 19 November 2022 (UTC)