Entered wrong base-coordinates, how to correct

your sorta right, and i dont remember now what i did (old age sucks!), maybe someone else has the recipe handy? inverse gives you direction and a ellipsoidal distance

Output from INVERSE

Ellipsoid : GRS80 / WGS84 (NAD83)
Equatorial axis, a = 6378137.0000
Polar axis, b = 6356752.3141
Inverse flattening, 1/f = 298.25722210088

First Station : from

LAT =  38 26 23.40361 North 
LON = 122 21 17.10942 West  

Second Station : to

LAT =  38 26 23.39630 North 
LON = 122 21 17.11819 West  

Forward azimuth FAZ = 223 19 30.4245 From North
Back azimuth BAZ = 43 19 30.4190 From North
Ellipsoidal distance S = 0.3099 m

look at ‘project points’, could be that but you may have to convert from meters maybe
image

update: ok i just tried this cause i know i am going to make this mistake again and should have made better notes in the first place. so ngs inverse is just one way to determine a distance and direction. the assumption here is that you have your faulty base coordinate written down (the one you used during your RTK job) and you have the value you wish you had entered. this is FROM and TO (what i wish i had entered) in my inverse above. if you dont then your gonna have to just guess or do the job over. so then i wanted to use ‘project points’ in QGIS but the damn thing wants the shift value in degrees (layer units : epsg4326) which is like 0.00000279…well ok fine…but then it auto truncates it to 0.000002…well thats not ‘right’!!, i want to plug in the value straight from inverse. so i decided to save the layer to state plane since i was going there anyway and i was able to shift it after taking 0.3099 m to feet. thats a bit more description for you on one way to proceed.

Is inverse necessary here? I don’t know enough here to understand. In QGIS you can add an X field and a Y field to your base station attribute table with the correct coordinates. You can then do something like X_Typo and Y_Typo and manually enter in your coordinates as entered into Reachview. Add an X_offset and Y_offset field to attribute table. Run field calculator and write a simple expression (X - X_Typo) to get the offset for X. You could also just use a regular old calculator.

But I prefer this way. You can just plot whole survey with offset as originally done with typo base coordinate included. You will have to add this but would be nice if Emlid did this for us anyways when exporting a survey to include the base. Then plot your correct base coordinate. Grab/edit all the points in your survey including the typo base. Then drag/snap the typo base to the corrected base coordinate thereby shifting all your survey points at same time. All done.

How do you postprocess the survey? Are you using Jurijs tool?

I would be interested how that compares with my script, maybe your solution? and how all of them compare to the infield/onboard calculations.

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