M+ Missing and extra events for PPK

Hi Guys,

First time posting here.

I have an M+ and I have tried a few times to process different jobs. The first time I had a mis-match between the amount of events and the amount of images that I had captured.

The second time I some how managed to get 15,500 events, only haveing captured 700 ish photos.

I am using the M+ on a P4 pro with the kit from Tuff wing. I have my own base station set up to process the PPK in EZ surv and I am following the tutorial on youtube from Mid South Drone services.

Could someone have a look at this file for me and see am I doing something wrong with the processing or have I done something wrong during the processing?

Does anyone have any tips or tricks on how to align a mis match between too many events vs photos or visa versa? apart from trying to match them in Excel or similar.

Thanks in advance

Reach will pick up almost every single variance in the triggersignal. If you have a bad connection or the trigger signal is weak/noisy this might create hugh amount of events in the raw file.
Makes sure you have a clean signal, good connection.

With so many events, its going to be hard lining up photos with the events.

I’m not sure if you are familiar with the kit from Tuffwing, I am unsure how there would be noise / weak Singal. I’ll have another go at it tomorrow and see if I can find any weak links with the wiring

Try move and wiggel/shake all parts from the camera to the Reach unit while having the Reachview up https://docs.emlid.com/reachm-plus/common/reachview/camera-control/
from here you can see if Reach creates an event (in the top right side of the screen).
You could try fly a mission without triggering the camera, no events should be created during this test.

2 Likes

Thanks TB_RTK for the tips. I Have other jobs where there are less events than there are photos. In this case do you have any tips on how to line up the events with the photos and possibly get it to line up? in EZ surv if you are out by one event / photo it will not write the updated exif.

Hi. This software should do the trick. Written by @kineo.

wsi-software.webbersurveying.com

Allows u 2 match up events with photos and create a control file for import into photogrammetry software. Should do fine with less events than photos. Might struggle some with your excess events case.

1 Like

Thanks wsurvey. This looks just like what I am after. Did you develop this software? Is it accurate enough to use the first photo to match the photos to the events? are you using it with much success?

hi donno,

It was written by Bill Webber @kineo. I have used it to match up photos for several test flights. You can select the best match pair that gives the most reliable number of matches. Because of the coarse nature of the DJI timestamps it may be that, for example, photo 2 and event 2 may give the best initial match rather than photo 1 and event 1. But you also get to set the tolerance for matches so if you set it wide enough it should get most of the available matches.

I understand thanks for the explanation.

In “Open custom position file” there is the option to open a file that has not come from RTKLIB. I am trying to open a file that I exported from EZ surv which has the format:
GPSWEEK,GPSSECOND,LAT,LONG,ELLHEIGHT and geo adjust does not like the formatting. any idea what format it like to see for date and time?

TIA.

I have not tried custom pos files. perhaps @kineo can chime in if he’s around.

I would suggest to use the same format as in the RTKlib pos files with YYYY/MM/DD and time to 3 decimals (I don’t think 5 decimals works). Also make sure your pos file time output is UTC instead of GPST, as the photos are most likely timestamped in UTC.

I also forgot to mention, if you didn’t know, logging of certain satellite constellations at some update rates causes missed events. I was logging GPS, GLO GAL, SBAS and QZSS i think at 5Hz and was missing heaps of events. I have no problems with missing events or fixed PPK tracks when logging GPS, GLO and GAL at 5Hz.

The custom position file was added for Phantom 4 RTK users which have the Timemark.mrk event file recorded in addition to the Rinex file. I have some users post processing the P4RTK rinex file with other software, so added that for them. I should probably make that more clear.

If you are using the Reach M+ and want to use GeoAdjust to sync your events and photos you should probably just use RTKLIB. If for some reason you need to use EZ Surv email me the position file and event file output from EZ Surv to geoadjust@gmail.com, and when I get a chance I’ll see if there is some work around.

This topic was automatically closed 100 days after the last reply. New replies are no longer allowed.