What is lamp_mount=angled_mast like?

Most of the tags related to highway=street_lamp are (for me) generally understandable ore at least well described.

I’m pretty sure that the left picture shows a “straight_mast”, the picture in the middle a “bent_mast”. Is the street lamp in the right an “angled_mast”?

Let’s have a look into the wiki: “angled_mast – A pole that starts out straight but then is (usually 90°) angled.”

Unfortunately there is no picture to this tag. My 1st interpretation was: it isn’t all about the pole and if the bulb is not centered above the pole but is angled to the side (street) - it is an angled mast. I was simply interpreting: angled_mast – A pole that starts out straight but the bulb then is (usually 90°) angled.

In the meantime I have some doubts and ask the community: what is an “angled_mast” really like?

Not sure where you are looking. But I see a picture on the wiki.

This one:

I don’t tend to map to that level of detail, but from the description it sounds like this example fits that description.

no, straight_mast (at least that is response I got when I asked it myself sometime ago)

o.k., my oversight, I stopped reading at the main page of Tag:highway=street_lamp - OpenStreetMap Wiki . Going forward down to Key:lamp_mount - OpenStreetMap Wiki , specifications are much more detailed.

For reference I would consider the left and right examples to both be straight masts (on the right because it’s only the lamp assembly which is at a right angle, not an offshoot of the mast itself). And the middle example is of course a bent mast as you said.

On this topic, where should we be mapping the actual street_lamp node?

On the pole itself, or out at the end of the mast where the light is actually located?

One would normally put the highway=street_lamp node where the base of the mast gets into the ground.

Two quotes from wiki, relevant for cases there the “light source” (=bulb) is not strait above the mast position:

en:wiki: “Add a node at the point where the light source is actually positioned”

de:wiki: “Position genau am Leuchtmittel setzen, nicht an der Mastbasis”

Both express to place the node for highway=street_lamp at the position of the bulb (light source).

I am (mis)reading it as entire street lamp being “light source”

In my editing area I have not seen anyone place highway=street_lamp on carriageway where it is overhanging from curved mast.

It is slightly—though really only just a tiny bit—misleading. The light source is the bulb (the part that shines), not the pole. The German text part, however, is unambiguous.

Is the wiki reflecting actual use? I always thought default OSM mapping is on ground level. For example if a roof reaches out, we try to map the building wall, not the roof edge.

It seems weird that street lamps were treated differently. Also it would be much harder to position the node correctly, because you cannot use the mast’s shadow in an aerial image.

Me neither. On the other hand nodes for wire supported lamps are set to the position where the lamp hovers above the street and not to the walls where the wire is attached (i.e. to house walls or poles). Not so much difference for me between a lamp mounted at the top of a widely bent mast and a construction by horizontal wires.

probably because

  • in regular cases you have two attachment points for a single lamp
  • it is still not attached to ground, so you cannot match ground point attachment location

How does it work in the case where the street lamp has two light bulbs (see): one lighting the highway and another lighting the sidewalk? Also ,as others have said, it would be strange to put the street lamp in the middle of the left lane.

3 nodes, 1 for the pole & 1 each for the 2 actual lights?

This is what gets mapped as “angled_mast” around here.

I marked that response

the solution to my question, because it’s the wiki. It shows an obvious different shape from a bent_mast.

I tend to trade other examples shown here in the thread

as bent_mast as well, because of their common design, different to wiki picture for angled_mast: a bulb in reasonable distance from the pole base. Whether the extenting arm is more or less curvy bent seems secondary to me.

Let’s add that to the wiki and wait for comments :wink: