[OSM-talk] When images are not calibrated

[stevea]

Addendum to my previous.  While I understand the original poster is from Sweden, and there are dozens (hundreds?) of geodetic data available that one might use (often an OSM user will select one of several from a usually-temporally-latest national-level geodetic datum, or perhaps WGS 84 if one is attempting to be "worldwide"), these truly are decades-long endeavors.  The study of geodesy goes back centuries, though "better mathematics" (due to spheroid calculations of Earth) began in roughly the 19th century, getting better in the 20th with satellites during the Space Age and even better in our present 21st with newer GPS technologies, more precise atomic clocks and computing technologies that are much further miniaturized and seemingly ubiquitous.  The data move through such fabrics, but only slowly.

For example, in the USA, we are planning the "Datum of 2022" to replace / supersede our current-era NAD 83 and WGS 84 by our National Geodetic Survey during 2024-25 to improve our National Spatial Reference System.  The older (NAD 83, NAVD 88...) rely on physical survey marks that deteriorate over time, and a newer datum with a newer geodetic reference frame that relies less and less upon "stones and survey markers" will only enhance precision.

Things like national land surveys, accuracy in calculations and display, and of course mapping will certainly follow from these continuing endeavors, but it does take time.

I can offer the medium-to-longer-term perspective that in my experience of 12 years in OSM, I have seen a statewide protected-area database, local (county-level) landuse polygons and even OSM itself harmonize and synchronize with better data that have become much better aligned (it must be with "reality itself") as we "watch each other" through years and years of updates and iteration:  this really happens.  But only over years and decades.

Have patience:  OSM is a long-term project.  Oh, and "map your best."