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Public-images-osm logo.svg seamark:fixme
This tag outlines known errors in respect to this seamark which

should be fixed.

Group: Marine
Used on these elements
may be used on nodes
use on ways unspecified
use on areas unspecified
use on relations unspecified
Status: unspecified

seamark:fixme=* is used in combination with OpenSeaMap/Lights Data Model to describe errors which are known and should be corrected manually. Many lights of Openseamap are imported automatically (see OpenSeaMap/List_of_Lights_Import). During parsing the raw data several errors may occur. Some of them are detected automatically but cannot be corrected by software. The reason for those errors is either because the parser incorrectly detected something or because of syntax errors within the original data. The data source of all lights is the List of Lights published by the US NGA as PDF documents. In the following we will refer to this list just as the LoL.

Note that the original documents are republished once a year thereby containing corrections. Thus, errors may change or may be fixed. All tagged errors refer to a specific version of the original documents. The origin and date of issue is kept within the source=* tag.



In JOSM SeaMapEditor all unverified lights objects are marked with a yellow star. This requires that the SeaMapEditor be loaded:
JOSM Edit menu, select "Settings" icon "socket" (plugins), click plugin "SeaMapEditor" check-box, "OK" and restart JOSM.

How to donnload and use JOSM



The positions items in the List of Lights are given to the nearest 1/10 minute, so they may have a positional error of 180m or more. Sometimes the data is not based on WGS84, and can result in positional errors of several hundred metres.
Therefore, each imported lights object is tagged with: seamark:fixme=please_fix_position. Please survey your area to find these seamarks and correct the position and any other incorrect data. Then delete the "seamark:fixme" tag.


In the Lights-FIXME-Chart you find all lights waiting for the right position...

Walk aroud the coast:

from z=6 you will see the light

Change to OpenSeaMap to look for lights:

in z=10..18 you will see the lights
in z=14..18 you will see "Check Position" (if there is)

Zoom in to z=18, select in the OpenSeaMap-menu (JOSM already started) "Edit by JOSM remote"

Select in JOSM in the menu "background" the "Bing" aero photos.
Move the light to the right position,
and delete the tag "please fix position".

The chart will be updated weekly.


Where there is already a mapped feature such as a man_made=lighthouse but without any OpenSeaMap tags, it must be merged with the imported lights object. In this case, the man_made=lighthouse can be taken to be in the correct position, and the imported seamark:type=light_major would have the correct seamark tagging:

  1. Search the coast for a man_made=lighthouse.
  2. Check with aerial photographs, whether the position is exact.
  3. Look for the matching "yellow star" it will most likely be a seamark:type=light_major very often it may have a seamark:longname=* tag which helps to compare or the tower height in a seamark:landmark:height=* tag or the height of the light in seamark:light:height=* may help.
    If there are other yellow stars within 1-2km, examine them all to be certain that the correct match has been made.
  4. be sure to have closed the sector window, if not close it.
  5. Copy the yellow star with <Ctrl-c>.
  6. Select the man_made=lighthouse and use <Shift-Ctrl-v> to add all the properties automatically.
  7. When you have verified that the position accuracy is within 20m (from accurate aerial images, local knowledge or survey), then delete the tag seamark:fixme=please_fix_position in the completed light and this will change the icon from the yellow star to light_major or light_minor black star.
  8. Erase the star no longer needed, and upload the result.

Value List

The errors sould be listed as a comma separated list.

Value Description
beacon_guess If a seamark is detected to be a lateral mark but not class (buoy, beacon,

float,...) was found it is assumed to be a beacon but this may be wrong.

height The height according to column 5 of LoL seems to be detected incorrectly.
intdup Column 1 of the LoL contains more then 1 light with this international

reference ID.

name_incomplete All names within the LoL end with a period otherwise it is tagged like

this. The names are contained within column 2 of LoL.

please_fix_position The LoL has a data accuracy of not more than 185 meters, hence, all lights

should be positioned accurately by hand. This attribute is set by default as long as it was not repositioned accurately.

rem_incomplete This is the same as name_incomplete but in respect to the Remarks

which is column 8 of LoL.

usldup Some lights have no international reference ID assigned but just an internal

number of the US NGA. If several lights with the same number exist, they are tagged like this.


If you like to care for an area:

Maintainer Area Pub.
Malcolm Pub114 (Great Britain, North Sea) 114
Bernhard Croatia, Greece 113
Dave Australia 111,112


Date lights FIXME diff FIXME cum OK %
2012-12-28 46'426 29'882 0 0 35,6
2013-01-04 46'845 28'211 1671 1671 39,8
2013-01-11 46'113 27'966 245 1916 39,4
2013-01-28 46'188 27'660 306 2222 40,1
2013-02-07 46'186 27'637 23 2245 40,2
2013-02-14 46'223 27'326 311 2556 40,9
2013-02-20 46'207 27'321 5 2561 40,9
2013-03-05 46'140 26'477 844 3405 42,6
2013-03-22 46'181 26'277 200 3605 43,1
2013-04-05 46'193 26'168 109 3714 43,4
2013-04-20 46'227 25'943 225 3939 43,9
2013-04-27 46'147 25'817 126 4065 44,1
2013-05-13 46'050 25'725 92 4157 44,1
2013-05-22 46'037 25'593 132 4289 44,4
2013-06-09 46'033 25'530 63 4352 44,5
2013-06-28 46'057 25'513 17 4369 44,6
2013-07-14 46'058 25'469 44 4413 44,7
2013-08-01 46'063 25'380 89 4502 44,9
2013-08-27 45'788 24'898 482 4984 45,6
2013-09-11 45'733 24'733 165 5149 45,9
2013-09-20 45'665 24'608 125 5274 46,1
2013-10-11 45'516 24'408 200 5447 46,4
2013-10-29 45'366 24'249 159 5633 46,5
2013-11-20 45'116 23'803 446 6079 47,2
2013-12-14 45'003 23'678 125 6204 47,4
2014-01-01 44.890 23.560 243 6322 47,5
2014-01-11 44.882 23.535 25 6347 47,6
2014-01-28 44.985 23.406 129 6476 48,0
2014-02-19 44-944 23.188 218 6694 48,4
row content
lights seamark:light:character=*
FIXME seamark:fixme=please_fix_position
diff FIXME seamark:fixme=please_fix_position (old) - seamark:fixme=please_fix_position (new)
cum Fixed lights since import
OK % (lights - seamark:fixme=please_fix_position) / lights