How the matching works
A GPX track is a list of positions, each with the time it was recorded,
in UTC. Your camera records the time each photo was taken
(DateTimeOriginal). The matcher turns that into the same UTC
time, finds the moment in the track, and reads the position recorded
then. If the photo falls between two GPS fixes, the position is
interpolated between them rather than snapped to one, so a burst taken
while walking does not collapse onto a single spot. It never interpolates
across a break between track segments.
What the numbers mean
- Time from a GPS fix is how far the photo is, in time, from the nearest real recorded point. A few seconds is a confident match; minutes means the position is a guess between distant points.
- Distance from it is how far the matched position is from that fix. On a sparse track, a short time can still be a long way.
- Outside the track means the photo was taken before the recording started or after it ended. Usually that is the clock, not the GPS.
- In a gap means the recording lost signal around the time of the photo, for longer than the match window.
Photos in the wrong place? It is usually the clock
Off by whole hours is a timezone: the camera recorded local time with no zone, and the matcher assumed a different one. Set the photo timezone, or apply the suggested offset. Off by exactly one hour is usually daylight saving. Off by seconds or minutes is clock drift. The suggestion can only find offsets that move photos onto the track; to measure drift, photograph a phone’s clock with the camera and compare. Fixing wrong geotags walks through all three.
Questions
Why only five photos? This is a free preview of one batch. The EasyGeotag app is built for a whole shoot.
Why no map? Map tiles come from a tile server, which would learn the area you are looking at. The plot is drawn locally from your track instead, so nothing leaves the page.
Where do I get a GPX file? From a Garmin or other GPS watch, a handheld GPS, a bike computer, or an app — see geotagging photos from a GPX file, or record one on your iPhone. Lightroom users: Lightroom Classic and GPX tracklogs.
Something not working? Write to contact@easygeotag.app.