Re: [Tagging] Difference between lighthouses and beacons

[Paul Allen]

On Sat, Jan 20, 2018 at 12:04 AM, marc marc 
wrote:

> Le 19. 01. 18 à 23:42, Graeme Fitzpatrick a écrit :
> > 1. A lighthouse is a usually tall building or tower that has a lamp at
> > the top.
>
> has or had
>

Irrespective of technical definitions, I think you'll find that most people
think a lighthouse
has a keeper dwelling within.  Those with slightly more knowledge
understand that many
lighthouses have been automated and no longer have keepers.  I think you'll
find that
most people would think the following things characteristic of a lighthouse:

1) Has a light at the top.  Not necessarily working.  Not necessarily with
any lamp
remaining.  But it has visible glass at the top which is (or was) there for
a light to
shine through.

2) Is large enough that it is capable of allowing at least one person to
reside within
even if nobody lives there now.

3) Is circular (or nearly circular) in plan view.  Other shapes are
possible, but circular is
the one most familiar to them.

That, I think, is pretty much how most people's minds work.  Show them a
photo of
such a structure (with the photo taken in daylight) and they'll identify it
as a
lighthouse.  If you then say it's been automated, they'll still say
lighthouse (for lack
of anything else to call it).  If you tell them it no longer operates
they'll say it WAS
a lighthouse and still identify it as a lighthouse.  If you mark something
on a map as
a lighthouse then that's the type of structure they'll be looking for.
They'll be looking
for that because most of them (at least those in the UK)  will have seen a
seaside
postcard featuring a lighthouse that looks like that.

Can I back that up?  Yep.  I just did a google image search for
lighthouse.  The
results weren't affected by any previous search I've done because it's the
first
time in my life I've used google to search for lighthouse.  Google's image
classifier
is based in large part upon users playing a "game with a purpose" that
presents
them with randomly-chosen images and they describe what's in the image.
Those
results are based on what people think a lighthouse looks like.  You can
see from
the results that most photos were taken in daylight and there's no way of
knowing
if the lighthouse was manned or had a working light.

Having said all that, I'll give my conclusion.  Any tagging that does not
conform
to user expectations will be misapplied by taggers and misread by
end-users, no
matter what the wiki has to say about it. If it looks like a lighthouse
(see google
images) then it's a lighthouse.  Whether it functions as a major light,
minor light,
beacon or doesn't function at all is for other tagging to describe.

 --
Paul
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[marc marc]

Le 19. 01. 18 à 23:42, Graeme Fitzpatrick a écrit :
> 1. A lighthouse is a usually tall building or tower that has a lamp at 
> the top.

has or had
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Graeme Fitzpatrick]

On 20 January 2018 at 08:18, Malcolm Herring  wrote:

> I think from all the cases presented in this thread, we could perhaps
> frame two broader definitions:
>
> 1. A lighthouse is a building that has a lamp room at the top.
>
> 2. A beacon is a mast surmounted by a light.
>

Pretty good, but I'd modify them slightly :-)

1. A lighthouse is a usually tall building or tower that has a lamp at the
top.

2. A beacon is a short mast surmounted by a light.
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Malcolm Herring]

I think from all the cases presented in this thread, we could perhaps 
frame two broader definitions:


1. A lighthouse is a building that has a lamp room at the top.

2. A beacon is a mast surmounted by a light.


___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Martin Koppenhoefer]

sent from a phone

> On 19. Jan 2018, at 03:16, Andrew Davidson  wrote:
> 
> Don't be too sure about that. I thought that we could all agree that a 
> lighthouse had some thing to do with light and houses, but it turns out 
> that's not an universally held opinion.


rather than light and houses it’s a house for the light


> "A tower that emits (or emitted) a light signal assisting navigation on sea."
> 
> which is what is in your photo above.


I would not have considered this structure a tower, but maybe in English the 
word can be used for a greater variety of things


cheers,
Martin 
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Philip Barnes]

On Fri, 2018-01-19 at 10:49 +, Janko Mihelić wrote:
> I think the border between lighthouses and beacons can only be fuzzy,
> we can never make a clear line. We can have a few pointers like
> "living quarters, big in size", but nothing set in stone. And that is
> ok because their purpose is the same, so some overlaping is not a
> problem. But I believe we do want to differentiate between this:

Lighthouses also flash, or at least the lens rotates giving each a
unique signature from which they can be identified by ships.


Beacons will tend to give a steady light.
Phil (trigpoint)___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Janko Mihelić]

I think the border between lighthouses and beacons can only be fuzzy, we
can never make a clear line. We can have a few pointers like "living
quarters, big in size", but nothing set in stone. And that is ok because
their purpose is the same, so some overlaping is not a problem. But I
believe we do want to differentiate between this:

http://static.panoramio.com/photos/original/44263014.jpg

and this

https://upload.wikimedia.org/wikipedia/commons/thumb/e/e5/Buoy_seal.jpg/250px-Buoy_seal.jpg

We have seamark tags that only look at their light and its properties, but
the man_made tag can look at the structure and how it looks and feels.

Janko
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Andrew Davidson]

On 19/01/18 13:23, Steve Doerr wrote:

Here's the OED definition:

'A tower or other structure, with a powerful light or lights (originally 
a beacon) at the top, erected at some important or dangerous point on or 
near the sea-coast for the guidance of mariners.'


That's pretty much the majority view of the very tiny, unscientific, 
sample of people, on this list, who have attempted a definition.


However, there is an alternative view that the definition should be 
based on the availability of accommodation for people within or nearby 
and the grandeur of the structure.


___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Andrew Davidson]

On 19/01/18 13:23, Steve Doerr wrote:


Depends what you mean by 'houses'. 


I was hoping we meant in the sense of providing space for. As in this 
structure houses a light.


___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Andrew Davidson]

On 19/01/18 01:25, Malcolm Herring wrote:

On 18/01/2018 13:52, Janko Mihelić wrote:

It is important mappers doing a surveys can apply correct tags to 
observed objects without any knowledge of their function.




Interesting tagging theory there. So I can only tag:

highway=road

because you need to know what function the road has to give it a 
hierarchy value? and:


highway=path

because you need to know what function it has before you can tag it 
footway or cycleway? and:


building=yes

and let's not forget:

man_made=tower

because you need to know what function a structure has before you can 
tag it man_made=lighthouse.


___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Steve Doerr]

On 19/01/2018 02:16, Andrew Davidson wrote:

On 19/01/18 00:52, Janko Mihelić wrote:

Ok, the discussion at least came to an agreement that this:

https://imgur.com/a/U8SXn

is not a man_made=lighthouse. 


Don't be too sure about that. I thought that we could all agree that a 
lighthouse had some thing to do with light and houses, but it turns 
out that's not an universally held opinion.


Depends what you mean by 'houses'. The purpose of a lighthouse is to 
house a light: it doesn't need to house people. Here's the OED definition:


'A tower or other structure, with a powerful light or lights (originally 
a beacon) at the top, erected at some important or dangerous point on or 
near the sea-coast for the guidance of mariners.'


--
Steve

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Andrew Davidson]

On 19/01/18 00:52, Janko Mihelić wrote:

Ok, the discussion at least came to an agreement that this:

https://imgur.com/a/U8SXn

is not a man_made=lighthouse. 


Don't be too sure about that. I thought that we could all agree that a 
lighthouse had some thing to do with light and houses, but it turns out 
that's not an universally held opinion.


We have A LOT of those mapped as 
lighthouses (I think the majority of that tag is on the wrong element). 


To be fair to those mappers you need to go back and look at how a 
lighthouse was defined in the wiki article (eg: from the beginning of 
2016 
https://wiki.openstreetmap.org/w/index.php?title=Tag:man_made%3Dlighthouse=1257147) 
where they are defined as:


"A tower that emits (or emitted) a light signal assisting navigation on 
sea."


which is what is in your photo above.

The trick would be to redefine what a lighthouse is so that mappers 
might have a chance of getting it "right".


___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Malcolm Herring]

On 18/01/2018 15:27, Janko Mihelić wrote:
I'm in the process of making a new icon, and I can make a pull request 
on the openstreetmap-carto soon.




That is good - maybe it will prevent mappers using "lighthouse" just so 
that a symbol is placed on the map.


I have added some more examples of non-maritime beacons to the tag page


___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Janko Mihelić]

čet, 18. sij 2018. u 15:27 Malcolm Herring 
napisao je:

> man_made=beacon *is* the appropriate tag for such structures. Tags in
> the "seamark" namespace relate only to the *navigational function* of an
> object, not the physical form. Many beacon objects have no navigational
> function & therefore do not carry "seamark" tags.
>

Ok, so man_made=beacon is used for the physical structure that is made to
cary the light, and the seamark tags are used to define what kind of a
light is it. That looks correct.

I'm in the process of making a new icon, and I can make a pull request on
the openstreetmap-carto soon.

Janko
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Malcolm Herring]

On 18/01/2018 13:52, Janko Mihelić wrote:
I looked at man_made=beacon. Taginfo says we have about 7 000 of those, 
and the wiki shows something that resembles what we are talking about, 
but not quite:




man_made=beacon *is* the appropriate tag for such structures. Tags in 
the "seamark" namespace relate only to the *navigational function* of an 
object, not the physical form. Many beacon objects have no navigational 
function & therefore do not carry "seamark" tags.


It is important mappers doing a surveys can apply correct tags to 
observed objects without any knowledge of their function.



___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Janko Mihelić]

Ok, the discussion at least came to an agreement that this:

https://imgur.com/a/U8SXn

is not a man_made=lighthouse. We have A LOT of those mapped as lighthouses
(I think the majority of that tag is on the wrong element). One reason is
rendering, and we have to start rendering something. The question is what.

I looked at man_made=beacon. Taginfo says we have about 7 000 of those, and
the wiki shows something that resembles what we are talking about, but not
quite:

https://wiki.openstreetmap.org/wiki/Tag:man_made%3Dbeacon

Maybe just start rendering seamark=beacon? We have only about 2 000 of
those, but we have 40 000 seamark:type="beacon_lateral" or
"beacon_isolated_danger" or "beacon_special_purpose". We can add
seamark=beacon to those.

The icon would be something like man_made=lighthouse, but thinner.

sri, 17. sij 2018. u 13:09 Martin Koppenhoefer 
napisao je:

>
>
> 2018-01-16 12:36 GMT+01:00 Malcolm Herring  >:
>
>> On 16/01/2018 10:25, Andrew Davidson wrote:
>>
>>> OK. So a lighthouse has to have a rotating light then?
>>>
>>
>> A lighthouse does not have any particular type of light, or any light at
>> all, but it will have a lamp room at the top
>>
>
>
> I guess an open fire would be OK as well? Let's not forget, lighthouses
> are much older than (electric) lamps.
>
> Cheers,
> Martin
> ___
> Tagging mailing list
> Tagging@openstreetmap.org
> https://lists.openstreetmap.org/listinfo/tagging
>
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Martin Koppenhoefer]

2018-01-16 12:36 GMT+01:00 Malcolm Herring :

> On 16/01/2018 10:25, Andrew Davidson wrote:
>
>> OK. So a lighthouse has to have a rotating light then?
>>
>
> A lighthouse does not have any particular type of light, or any light at
> all, but it will have a lamp room at the top
>


I guess an open fire would be OK as well? Let's not forget, lighthouses are
much older than (electric) lamps.

Cheers,
Martin
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Malcolm Herring]

On 16/01/2018 10:25, Andrew Davidson wrote:

OK. So a lighthouse has to have a rotating light then?


A lighthouse does not have any particular type of light, or any light at 
all, but it will have a lamp room at the top



___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Andrew Davidson]

On 16/01/18 21:17, Martin Koppenhoefer wrote:
can't see a lighthouse in your link. 


It's the really big building with the beam of light coming out of 
it--you can't miss it


This is a photo of the Rome 
lighthouse (it is also called "lighthouse", and has a rotating light):

https://upload.wikimedia.org/wikipedia/commons/9/98/Roma_2011_08_15_Faro_di_Roma.jpg


OK. So a lighthouse has to have a rotating light then?

___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Martin Koppenhoefer]

2018-01-16 11:04 GMT+01:00 Andrew Davidson :

>
> Oh my. Hope someone has mapped the lighthouse in Las Vegas (
> http://vegasvacationbids.com/luxorhotelatnight.jpg).



can't see a lighthouse in your link. This is a photo of the Rome lighthouse
(it is also called "lighthouse", and has a rotating light):
https://upload.wikimedia.org/wikipedia/commons/9/98/Roma_2011_08_15_Faro_di_Roma.jpg

Cheers,
Martin
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Andrew Davidson]

On 16/01/18 20:32, Martin Koppenhoefer wrote:


sure, for example here's a "famous" lighthouse in Rome, far from the sea:
https://www.openstreetmap.org/node/249332339



Oh my. Hope someone has mapped the lighthouse in Las Vegas 
(http://vegasvacationbids.com/luxorhotelatnight.jpg).


___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Andrew Davidson]

On 16/01/18 19:34, Malcolm Herring wrote:
The main point that I was trying to make is that a simple pile or 
lattice tower with a light on top should not be tagged as 
man_made=lighthouse, but man_made=beacon.


Not always. A lighthouse is a structure housing a major marine 
navigation light. What a major light is less clear but usually has a 
nominal range of 15 nmi or more.


This 
https://www.unc.edu/~rowlett/lighthouse/photos/Australia2/EmeryPointNT.jpg 
is Emery Point Lighthouse. It has a nominal range of 19 nmi and is a 
major light.


Alternatively you can use the wiki definition for man_made=lighthouse; 
which is that any tower carrying a navigation light is a lighthouse. 
Only problem is that some lighthouses like this Canadian example:


http://www.brucebaycottages.com/fileman/Uploads/Images/mckay-island-lighthouse-bbc.jpg

wouldn't be a lighthouse as it's not a tower.

___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Martin Koppenhoefer]

2018-01-16 10:13 GMT+01:00 Malcolm Herring :

> On 16/01/2018 08:43, Martin Koppenhoefer wrote:
>
>> probably with exceptions, e.g. this is a lighthouse from 1911 (i.e.
>> historic) with a lattice structure, generally considered a lighthouse:
>> https://en.wikipedia.org/wiki/Adziogol_Lighthouse
>>
>
> I can see a house!
>
> To be clear, the OP asked what the difference is between a lighthouse and
> a beacon, not the difference between a major light and a minor light.



yes, there's a house, what I wanted to "prove" is that there are lattice
towers which are considered lighthouses, in response to "The main point
that I was trying to make is that a simple pile or lattice tower with a
light on top should not be tagged as man_made=lighthouse, but
man_made=beacon."



> The two classes of objects overlap, but are not equivalent. Only objects
> that have a maritime navigation function carry "seamark" tags. Many
> lighthouses & beacons do not.
>


sure, for example here's a "famous" lighthouse in Rome, far from the sea:
https://www.openstreetmap.org/node/249332339

Cheers,
Martin
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Malcolm Herring]

On 16/01/2018 08:43, Martin Koppenhoefer wrote:
probably with exceptions, e.g. this is a lighthouse from 1911 (i.e. 
historic) with a lattice structure, generally considered a lighthouse:

https://en.wikipedia.org/wiki/Adziogol_Lighthouse


I can see a house!

To be clear, the OP asked what the difference is between a lighthouse 
and a beacon, not the difference between a major light and a minor 
light. The two classes of objects overlap, but are not equivalent. Only 
objects that have a maritime navigation function carry "seamark" tags. 
Many lighthouses & beacons do not.


There is obviously a grey area between lighthouses & beacons. To tag an 
object as either requires some degree of subjective judgement, since the 
distinction is one of the structure's grandeur.



___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Martin Koppenhoefer]

2018-01-16 9:34 GMT+01:00 Malcolm Herring :

> On 16/01/2018 00:21, Graeme Fitzpatrick wrote:
>
>> In what way would you consider that these are not lighthouse's? Just
>> because they don't have accommodation?
>>
>
> Point taken. I was referring to the historical structures rather than any
> modern replacements.
>
> The main point that I was trying to make is that a simple pile or lattice
> tower with a light on top should not be tagged as man_made=lighthouse, but
> man_made=beacon.



probably with exceptions, e.g. this is a lighthouse from 1911 (i.e.
historic) with a lattice structure, generally considered a lighthouse:
https://en.wikipedia.org/wiki/Adziogol_Lighthouse

Cheers,
Martin
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Malcolm Herring]

On 16/01/2018 00:21, Graeme Fitzpatrick wrote:
In what way would you consider that these are not lighthouse's? Just 
because they don't have accommodation?


Point taken. I was referring to the historical structures rather than 
any modern replacements.


The main point that I was trying to make is that a simple pile or 
lattice tower with a light on top should not be tagged as 
man_made=lighthouse, but man_made=beacon.



___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Graeme Fitzpatrick]

On 16 January 2018 at 02:58, Malcolm Herring  wrote:
>
>
> A lighthouse (man_made=lighthouse) is a tower with living quarters either
> within the tower, or a separate structure at or adjacent to the base. They
> are topped with a lamp room. The lamp may or may not be functional - many
> lighthouses have been decommissioned from their navigation role. The
> distinguishing feature to differentiate lighthouses from masonry beacons is
> the ability to be lived in (do they have a door and at least one window?)
> and an enclosed lamp room at the top.
>

Sorry, will have to disagree with you there.

Australia has ~350 lighthouses, of which none are now manned. Some of them
are still operating in their original towers, but the majority are now
relatively simple structures eg
https://en.wikipedia.org/wiki/Point_Danger_Light &
https://en.wikipedia.org/wiki/Point_Cartwright_Light. In what way would you
consider that these are not lighthouse's? Just because they don't have
accommodation?

If a structure is designed & intended for long-range, coastal / offshore
navigation, it should be called a lighthouse (major light). If it's only
for short-distance navigation within the confines of a harbour, river, bay
etc then it's a beacon (minor light)
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Mateusz Konieczny]

On Mon, 15 Jan 2018 16:58:49 +
Malcolm Herring  wrote:

> A lighthouse (man_made=lighthouse) is a tower with living quarters 
> either within the tower, or a separate structure at or adjacent to
> the base.

Probably usually it is true but I would not consider it as absolutely
necessary.

___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Malcolm Herring]

On 15/01/2018 14:29, Martin Koppenhoefer wrote:

can you please explain how to distinguish a beacon from a light house?


Historical beacons (for which the tag man_made=beacon is appropriate) 
are structures that were for generic signalling purposes, not 
necessarily maritime navigation. They can found inland as well as on 
coasts. They usually take the form of either a masonry tower with an 
open top or else a simple pole with a fire cage on the top.


Maritime navigation beacons, on the other hand, can take many forms - 
everything from a tree branch driven vertically into the seabed, through 
poles, piles to masonry or metal lattice towers. They can be on the 
coast or offshore. They may or may not have lights. They are usually 
painted in internationally recognised colour schemes & may be topped 
with cones, cylinders or spheres. The colours & top shapes indicate the 
navigation information or warning.


A lighthouse (man_made=lighthouse) is a tower with living quarters 
either within the tower, or a separate structure at or adjacent to the 
base. They are topped with a lamp room. The lamp may or may not be 
functional - many lighthouses have been decommissioned from their 
navigation role. The distinguishing feature to differentiate lighthouses 
from masonry beacons is the ability to be lived in (do they have a door 
and at least one window?) and an enclosed lamp room at the top.



___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Martin Koppenhoefer]

2018-01-14 14:47 GMT+01:00 Janko Mihelić :

> A map with lighthouses was produced [1] that gained popularity because it
> was nicely rendered, but it showed how flawed OSM data was in this regard.
> Very often little beacons [2] are mapped as man_made=lighthouse, which is
> not right.
>
...
[2] - https://wiki.openstreetmap.org/wiki/Seamarks/Lights


can you please explain how to distinguish a beacon from a light house? I
cannot even see from the linked page, which tag to apply to a beacon [2],
nor is there a definition of either. The image for minor lights is not
readable (stamp size only. 135x100px).
https://wiki.openstreetmap.org/wiki/File:Minor_Light.png



> Lighthouses are big structures that were built to have living quarters for
> people that operated them.
>


I guess this is just a small part of all lighthouses, certainly there are
smaller ones as well?


Cheers,
Martin
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[Malcolm Herring]

On 14/01/2018 13:47, Janko Mihelić wrote:
So a fuzzy rule can be created, you can't have a man_made=lighthouse tag 
and seamark:xxx=yyy tags on the same object. That's instantly an error. 
Seamark tags are used for instruments that help navigation, and 
lighthouses are structures that can house those instruments. But they 
are not the same thing. So a lighthouse can be an area with a seamark 
node at the place where the light is.


Is this generally accepted?


No. Lighthouse objects mapped as building outlines should have any 
seamark tags on the way as opposed to a separate node. This arrangement 
is easier to maintain. As most lighthouses have their lamp centrally 
placed in the building, the light position can inferred by calculating 
the centroid of the area.


The bigger problem is defining exactly what is a lighthouse & what is 
just a beacon. I agree that a lighthouse should be a building with 
living quarters. Often beacon towers, whether masonry or metal towers 
that support a navigation light are tagged as lighthouses - which is 
incorrect. Part of this is 'tagging for the renderer', so that a symbol 
is placed on the main map, but often it is the lack of a clear 
definition of a lighthouse.



___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging

Re: [Tagging] Difference between lighthouses and beacons

[marc marc]

Le 14. 01. 18 à 14:47, Janko Mihelić a écrit :
> a lighthouse can be an area with a seamark node at the place where 
> the light is.

theoretically the difference seems correct to me.
but if someone just wants to map a lighthouse, he'll do it with a simple 
node. you cannot require that anyone who wants to add a lighthouse must 
have a sufficiently accurate source to be able to see the area used by 
the lighthouse.
Therefore, when the lighthouse is mapped as a simple node,
it seems normal to me that the seamark tag is on the same node as the 
lighthouse.

Regards,
Marc
___
Tagging mailing list
Tagging@openstreetmap.org
https://lists.openstreetmap.org/listinfo/tagging