Talk:Tag:man made=telescope

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X-ray telescope

For X-ray telescope you should instead of telescope:type=gamma maybe better telescope:type=radio + telescope:spectrum=nnn

The tag can then be evaluated more easily.--geozeisig (talk) 06:22, 16 September 2018 (UTC)

telescope:type or telescope:sensing ?

Much rather be more specific in what is meant by this tag. There is already the tag frequency=* that can be used. Light/optical and radio are a fairly broad band of frequencies. Warin61 (talk) 05:31, 23 November 2018 (UTC)

Type vs spectrum

@Jeisenbe: https://wiki.openstreetmap.org/w/index.php?title=Tag:man_made%3Dtelescope&oldid=2013609 I don't understand your comment. Radio and optical already describes a part of the spectrum. We don't need to know their exact frequency to be able to describe in what spectrum they operate in. frequency=* exists for the exact frequency in parallel. Anecodotally, there's 10 instances of telescope:spectrum=light (which may not be the best value). This is a possible interpretation. It would fit the role to "broadly categorise the spectrum that the telescope senses" (Key:telescope:type#Usage more. Furthermore, half of telescope:spectrum=* actually records the wavelength, suggesting these properties can be separated. For "appearance", the presence of a dish can be indicated by some other tags.


Of interest:

seamark:light:wavelength=* seamark:radar_transponder:wavelength=* communication:amateur_radio:beacon:wavelength=*

-- Kovposch (talk) 09:14, 20 July 2020 (UTC)

The tag frequency=* seems like a confusion of that key, because most uses of frequency=* are for a single number (usually with power=* features), but telescopes operate in a range of spectrum, rather than at one specific frequency. However telescope:spectrum=* is certainly nice to add if you can verify this information. But in most cases mappers will not have access to that information without consulting another database or searching documents: telescopes do not usually have a sign next to them which states the spectrum which they can observe. When surveying a location or mapping from aerial imagery, the information that is clearly accurate is that this is a radio telescope, or an optical telescope, because the construction of these devices is very different. --Jeisenbe (talk) 15:24, 20 July 2020 (UTC)
Why should frequency=* not allow a value range then? There are already tuples in use for frequency converter, and rectifiers or inverters. At least 2 telescopes have be tagged as such, frequency=80 -300␣MHz within way 607964749, and frequency=0.7 - 1.8 GHz around node 2377898990 (sorry website is overloaded). Bloating into a telescope:spectrum:frequency=* (and telescope:spectrum:wavelength=*) doesn't seem neccesary; neither does rejecting something as telescope:spectrum=optical and telescope:spectrum=radio. -- Kovposch (talk) 14:23, 21 July 2020 (UTC)

This is based on acknowledging the use of telescope:type=phased_array before. The observation subject, as in telescope:type=solar (5 instances), can also get stuffed into telescope:type=*.

-- Kovposch (talk) 09:16, 20 July 2020 (UTC)

A phased array is a radar device, not an observational radio telescope. A phased array emits radio waves, it does not receive them, if this Wikipedia article is accurate: https://en.wikipedia.org/wiki/Phased_array
It's describing an electronically-scanned array, as defined in the lede. A telescope, be it radio or optical (there are optical phased array), can be a "phased array" in the antenna array sense. I do agree this isn't the best value (eg as proposed for antenna:configuration=phased_array in Proposed_features/antenna:use). -- Kovposch (talk) 14:23, 21 July 2020 (UTC)
A solar observatory is quite different than an ordinary optical telescope: a standard optical telescope will be damaged if it were aimed directly at the sun, so I am fine with using a different value for this. --Jeisenbe (talk) 15:24, 20 July 2020 (UTC)
But the point is they are both optical telescopes, so a tag in use could be documented to classify and distinguish them better. -- Kovposch (talk) 14:23, 21 July 2020 (UTC)

Other issues: In theory, radio bands can be used to describe the spectrum specifically. On the other hand, the definition of "radio" wave and "microwave" very often varies. -- Kovposch (talk) 09:27, 20 July 2020 (UTC)

General consolidation of the values

See the overview in https://wiki.openstreetmap.org/wiki/Talk:Tag:telescope:type%3Dradio rtfm Rtfm (talk) 13:53, 20 December 2020 (UTC)