Let's say you have a point that your base is set up on. 5000 over 5000.
You go half mile down the road and take a shot. How does your GPS derive the bearing between the two points?
> Let's say you have a point that your base is set up on. 5000 over 5000.
> You go half mile down the road and take a shot. How does your GPS derive the bearing between the two points?
It depends upon how I instruct it to do so. How did the GPS salesman tell you to do it?
I think you are answering your own question, please, please before starting a job, decide on a projection, set up your data collector and your computer files with it.
I would suggest a state plane one but if you want a ground based kinda true north system on site have someone show you how to set-up LDPs and use them. You will then have a basis system and meta-data to use. And it will be stable and something another surveyor can retrace.
A GPS vector between two points with no tie to any CORS or control will give a very accurate bearing and distance between the two. That would geodetic north. However, the azimuth between two autonomous positions (i.e no baseline between them) would likely be way off.
That's truly terrible. We fight over the minutia of whether or not to put days that data was gathered on or reference stations used in the determination of the OPUS solution. This cat just said to hell with that popppycock and threw down and rolled on.
SMH
The real offense there is the font. Is that papyrus? Whatever it is, looks like something on the side of one of my wife's lotion bottles, not something that belongs on a survey.
> BEARINGS ARE REFERENCED TO GRID NORTH, BASED ON GPS OBSERVATIONS AND CONFORM TO THE NORTH DAKOTA COORDINATE SYSTEM OF 1983, NORTH ZONE (INTERNATIONAL FOOT). THE CONVERGENCE ANGLE AT THE POINT OF BEGINNING IS __°__’__._”.
That's pretty good and much like a statement I have used. I might add .... BASED ON UNRESTRAINED GPS OBSERVATIONS .....
I also like to make a statement of the CSF at the site and incorporate it in the B.O.B.
FWIW, it's just so, soooo easy to collect receiver data while you RTK, send it into OPUS, and shift your coordinates onto a real basis - and thereby create a data set of positions that are recoverable (at least searchable) relative to the national datum, that IMO it is poor practice not to do so.
:good:
