Reading OPUS Solutions Report

Does anyone have a good link that breaks down what the OPUS solutions report is comprised of and how to best understand it?

https://geodesy.noaa.gov/OPUS/about.jsp

Yeah I read this. Was looking more for a dummies guide.

Is this what I would use to enter into the base mode section or does this need converted to WGS84?

LAT: 40 23 52.95955 0.004(m)
W LON: 80 11 24.19541 0.005(m)
EL HGT: 247.787(m) 0.006(m)

Latitude: 40.235295955
Longitude: -80.112419541
Height: 247.787

Maybe someone can assist me. I’m trying to determine what target coordinate system I need to convert these coordinates to for the base mode?

LAT: 40 23 52.95955 0.004(m)
W LON: 80 11 24.19541 0.005(m)
EL HGT: 247.787(m) 0.006(m)

How are the coords derived ? What was used to compute these coords ? Where did they come from ? Is the height an ellipsoid height or orthometric (approx ground) height ? Are you setting up your own permanent base station ?

M2 that is set up as a base station and the antenna is static on the building.

I used ran the M2 for four hours and then ran it through OPUS. Those are from the solution report. I’m trying to determine how I take the coordinates from the report and use them in the base.

You can use as is, just make sure you select the same coordinate system that they are computed in. I’m assuming the elevation is orthometric, correct ?

No the VRS system is in ellipsoid so I collected in ellipsoid for that point also.

Ok, the OPUS report gives both ellipsoid and orthometric heights. Once you get setup, you should check in to a passive station (NGS monument) that might be near your base. You might be surprised how accurate your base computed position is.

https://geodesy.noaa.gov/NGSDataExplorer/

Given that I didn’t measure the distance from the arp to the ground level, I figured using ellipsoid was the way to go?

For the base station, you don’t need the ground. ARP would be the actual coord reference. That’s the way all the CORS positions are computed to.

So which is reflecting the exact center position of that antenna? Ellipsoid or Orthometric?

Whatever you want to use. NGS OPUS report shows both ellipsoid and orthometric. Our RTN uses ellipsoid heights, however the controller at the rover computes the actual orthometric.

If you are using your own base, you need to use orthometric, it’s just like using radio RTK except you are using internet.

I was under the impression that if I have the base set up using ellipsoid and then when in the field with my RS2 and RV3, I select the geoid and NAVD88 and RV3 would make the adjustments to ground level?

I’m really not that familiar with the app, my M2’s are used for static. Michael Lambert and others here on the forum could give you that detail. Wizprod is very knowledgeable using the app. I’d pm him or Emlid for the answer. Sorry I couldn’t help

This is correct.

This seems to be what you need to use.

However, remember to use a very long obs for establishing a permanent base.

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I ran a four hour, eight hour and a ten hour observation. Would I enter this below exact as is into the base section?

402352.95955
-801124.19541
247.787

Nope, you need the decimal degree format for ReachView to understand it.

Recommended website that I could use to convert it? I’ve used his one before but not certain on the source and target systems to use to convert it.