Best Solution (as of the time of this edit): Upgrade to Pix4D 4.4.9. As of the time of this edit-entry it isn't part of the automatic update but is available at https://cloud.pix4d.com/download/
Is there any way to get the Mavic 2 to record the GPS EXIF tags correctly?
We use DJI mavic drones for photogrammetryand engineering mapping. We've used the Mavic 1 in the past before without issues but we are now having significant problems with the Mavic 2 files. We took several hundred photos of an area withe the Mavic 2 and processed it in Pix4d (the photogrammetry package we use). The location of the resulting map model was off by hundreds of feet. We've replicated this same errored result in several other locations. After posting on the Pix4d website forum for a resolution (This is the link to the original forum post I made: https://support.pix4d.com/hc/en-us/community/posts/360022989372-Pix-4D-Mavoc-2-Processing-Issues) it seems the issue is that the Mavic 2 is storing GPS in two different locations as both XMP and EXIF tags....and the EXIF tags are actually incorrect (read below for more details on that). Unfortunately, these same EXIF tags are what Pix4D reads. So is there any way to get the Mavic 2 to record the GPS EXIF tags correctly or can we excpect that in an update soon?
Hello Jack, After some investigation, I found out what is going on and the reason for your displacement or the reason why Pix4D is locating the images far away from the place where they were really taken. I have opened the EXIF data embedded in your TIFF files. If you do that, you will see that your images have two places where the GPS coordinates are stored and they are different: 1.XMP tags
Xmp.drone-dji.Latitude XmpText 11 +30.2967378
Xmp.drone-dji.Longitude XmpText 11 -97.2779208 They are coming from your DJI drone and they show you the right coordinates, where the flight was really taken, which is to say, over the road. 2. EXIF tags: Exif.GPSInfo.GPSLatitudeRef Ascii 2 North
Exif.GPSInfo.GPSLatitude Rational 3 30deg 17' -13.140"
Exif.GPSInfo.GPSLongitudeRef Ascii 2 West
Exif.GPSInfo.GPSLongitude Rational 3 97deg 16' -20.967" This is the place where the coordinates are usually stored and where Pix4D takes them from.
If you do the conversion from Degrees,Minutes and Seconds to Decimal degress , what you have is: 30.28698°
-97.27249° Which differs in more than kilometer from the coordinates from the XMP tags. That means that the drone is storing two different coordinates for each photo and they are far away from each other. In addition to that, the seconds have a negative sign, so Pix4D is subtracting that amount of seconds to the minutes, so what Pix4D is really taking is: 30 deg 16' 46.86" 97 deg 15' 39.033" Converted into decimal degrees: 30.27968340 -97.26084254 Which is the place where the images are located in Pix4D's map view. Are these TIFF images generated automatically from the DJI or it generated JPG and they were converted into TIFF? You can find more information abot the EXIF and XMP information read by Pix4D here. If you want to use the real position, they must be stored in the EXIF tags and not in the DJI XMP tags. I show you in Google Earth the differences between the three positions: It would be good to know why the drone is storing two different sets of coordinates which are more than 1 km away, and why the seconds are stored with a negative sign. Maybe you can contact the drone or camera manufacturer. Regards.
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