OpenStreetMap

Messinian's Diary

Recent diary entries

I was doing some HOT mapping on an old project in Nigeria recently and noticed that depending on how I access the project, I get different versions of the Bing imagery.

If I use the HOT tasking manager (either using iD or JOSM) or direct JOSM download as a starting point I get a lower resolution image that is clearly a different vintage than if I open it direct from the OSM page through the iD editor.

I can’t tell which is more recent as buildings appear and disappear in Nigeria so no telling without some local knowledge.

Someone suggested that it’s likely due to accessing different API endpoints (which I don’t quite know what this means).

Time for some more investigating. I’d love to be able to use both sets of images. Maybe I’ll post on why I want to do that as a separate entry when I get a free moment.

Location: Yali, Ganjuwa, Bauchi State, Nigeria

I’ve learned quite a bit over the last few weeks, so I’m re-doing some of my earlier entries.

Notes for self and others: Based on local knowledge I’ve been able to determine that the PEMA ortho images are newer than the NYS Orthos, but not by much; these are both newer than Mapbox, but Mapbox is higher resolution/clearer.

both PEMA ortho and NY Ortho appear to be positioned pretty well in the Great Bend area, but Mapbox needs to be adjusted.

ESRI world seems to use the NY Ortho in this area and their positioning is shifted slightly to the north relative to the PEMA and NYS Orthos, but it seems to be registered fairly well overall. I would tend to believe ESRI in general, but the state Orthos may be better aligned for this area. Either way, it’s a negligable shift.

Bing: don’t bother; horrible for this rural area.

Can’t tell the vintage/date for the USGS 3DEP DEM model in this area. There is a much higher resolution Lidar dataset on the USGS website.

Location: Great Bend Borough, Susquehanna County, Pennsylvania, 18821, United States

About me

Posted by Messinian on 25 July 2021 in English.

I’m a recently retired senior leader/exploration geologist after 23 years working for a major international oil and gas company. I’m familiar with GIS systems, but not an expert by any means.

I spent a large portion of my career mapping remote sensing data in order to determine what lies below the surface of the earth. In my case this was primarily seismic data and well log data, but occasionally magnetic or gravity data.

I’m looking for some fun things to do so I started contributing to OSM.