Emlid Reach RS2 (North Carolina)
I was lucky enough to have a member let me test drive the RS2 for a couple weeks. I made sure to test as much as I could. The below is what I found.
Using the provided app with NC VRS login credentials the unit worked surprisingly well and accurately when fixed. 75% of the time it fixed with no troubles the other 25% of the time I found myself waiting 1-3 minutes before deciding to dump satellites and reestablish. Upon reestablishing the unit became fixed relatively quickly. In open sky areas I didnt have any trouble with Rapid Static or utilizing VRS. In Canopy (I realize multipath is a thing, but the technology is getting to a point where gps can accurately be performed in certain canopies using proper procedures at least with Trimble boards) it took longer to initialize sometimes in the 1-5 minute range and as stated previously i did have to dump satellites in order to gain fix a few times, but when fixed it was still surprisingly accurate. I always consider GPS to be accurate to +/- 0.2' if used properly. I have found it can be much more accurate than that, but if I stick to 0.2' when talking to clients i am comfortable that it will perform to that. When comparing to control I already had established the horizontal was typicaly 0.1' and the vertical was typically less than 0.2'.
Since I was using the app i used Calrson Survey to convert Lat Long to State Plane coordinates for comparison to the existing control. For the vertical I used the difference in Ellipsoidal Height of a near by NGS monument to Orthometric and applied that to the ellipsoidal heights provided by the app. There is more than likely a little be of slop in the vertical method especially. I did try to use corpscon and uploade the Geoid12b as shown by these directions( https://rplstoday.com/wp-content/uploads/converted_files/360157=3144-CoP%20Bulletin%20-%20Feb2016%20-%20Corpscon-Geoid12b.pdf ), but was unable to find the "geiod12b.txt" to download. I found all the .bin files but no .txt. Hints why I just used the difference of the nearby monument with this just being a test. I also setup on said monument and the Ellipsoidal Height difference was less than 0.1'. Once establishing a fix in canopy of any sort it was quickly lost when the instrument was evenly slightly moved.
Static and Rapid Static was a little trickier, and of the 6 I took I was only able to get 4 to process. The 4 that did process came in at the desired location within 0.1' Horizontal and Vertical and were all Rapid Static. The Static position I took I have yet to be able to get processed. I plan on uploading it again in the coming days to see if it will work now that it has been a substantial time since taking the Static location. 4 out of 5 of the rapid static shots processed and were acceptable. The 5th was taken under fairly heavy canopy so its not a big surprise that it didnt work.
I did establish a connection with SurvCE, but didnt have time to fully test that function. I can tell you when running with SurvCE and recieving corrections I was getting accurate Coordinates and elevations, so I assume it would work fine with a topo, but again, I didnt fully test it.
The wifi fucntion of the unit was a little different. You start off establishing a connection with the unit using wifi then tell it what network you want it to go to. Once its on the desired network you join the same network with our device and use the app. It should be noted that the onboard wifi is relatively weak and seemed to get 30' at best.
All that being said for $2,000 I think its a good product for that money, however it doesn't compare to the high dollar units running trimble boards. The trimble boards seem to retain fix far more reliably in canopy than this unit does. With that being said I plan on ordering one as most my work tends to be front end work where I may be using it to bring my survey to Grid and proper elevation. If I were doing any stakeout with GPS I would be hesitant at best to use the Reach. Not saying it wont do it, as a matter of fact it will even with the app, but reliability matters when doing stakeout for obvious reasons.
If others use it with SurvCE feel free to let me know your experience with that. If anyone has any questions I may be able to answer feel free to reach out and ill do my best.
I just found the utility in Carlson for elevation conversion Points->Point Utilities->Geoid Utilities. Just subtract the Geiod you want it converted to and bam converted from ellipsoidal height to orthometric height.
For horizontal conversions from Lat Long to State Plane Points->Coordinate File Utilities->Coordinate transformation