I’ve been contributing to OSM for quite a while now, and I’d like to start doing some mapping on OHM too, because I find it a really interesting project, but I have at least one beginner’s question and will probably think of more…
I noticed that iD for OHM includes all the old versions of Esri, rather than just the latest like for OHM, and I’ve read the corresponding GitHub issue. But do we actually have permission to use it for mapping on OHM? If I recall correctly, the FAQ on the wiki said that for OHM we’re only supposed to use Mapbox Satellite (for now), and the page about Esri itself also suggests that the imagery is only supposed to be used for ODbL-licensed mapping on OSM…
It sounds like you stumbled upon this GitHub issue and this wiki page, which were written before OpenHistoricalMap formally affiliated with OpenStreetMap through OpenStreetMap U.S., a local chapter of the OpenStreetMap Foundation. I’ve updated both to reflect the current state of affairs.
Speaking for the OHM advisory group, to the best of our knowledge, contributors do have the right to trace from the imagery layers that OSM uses, including Esri World Imagery and Esri World Imagery Wayback. Esri’s layers are provided for vectorization in open data sites in general. We’ve been in touch with Esri staff throughout the process of integrating the Wayback imagery into iD. The terms of use note that anyone contributing data to OSM via the ArcGIS platform agrees to place it under the same license as OSM (giving the ODbL as an example). However, the OHM database is in the public domain unless otherwise noted.
Regardless of copyright considerations, it remains important to keep a paper trail. When you use any of the built-in imagery layers in iD, your changeset will cite the layer in the imagery_used=* tag, which is sufficient in general. If your use of one layer versus another is especially relevant to how you mapped it, for example because it contradicts other published sources, then you can also cite the layer on the feature itself using the Source field.
Yes, that’s exactly what I saw. I’m so glad to hear the situation’s more straightforward than those made it sound! Thanks for clarifying!
Makes sense! The need for a paper trail matches up very well with my own instincts on how things should be done!
On a related note, the wiki also mentions the concept of using copyrighted newspaper articles to get names and dates. Are newspaper articles just given as an example, or are there any cases where it might not be OK to pick up dates from a source that’s still in copyright?
It’s just an example. Individual raw facts aren’t copyrightable regardless of the medium. Just be careful about copyrighted maps: although maps can also contain raw facts, it’s difficult to separate the facts from the depiction, so it’s best to steer clear of them.
Thanks for clarifying!