Hi. It has been awhile since I have collected ground control points and I am new to the Emlid workflow. I am getting high RMS values from OPUS. Latest one had the following: NORMALIZED RMS: 0.400
I would like to know if my workflow seems correct.
Here is the workflow.
On Emlid Flow base settings
Select all satellites *
Update rate set to 5 hz *
RTCM3 messages with ARP Station Coordinates set to 0.1 hx and MSM4 to 0.5 hz*
Base Output set to LoRa *
power 20 dBm*
air data rate 9.11 kb/s*
Rover settings
Set GNSS selections to same as base *
Set update rate to 5 hz*
Base collects for 3+ hours*
GCPs placed and Rover captures data at each one
Solution status during collect shows Fix
Wait 24hrs
Process rinex file on OPUS
Use values to correct the Base in post process on Emlid Studio
I would personally let the base log for min 4 hours, 7-8 hours ideally.
Clear sky view? No tall buildings, trees or obstructions adjacent or nearby clipping satellites? No electrical or radio disturbance. Photos of environment?
Are you using the regular GPS only OPUS or the OPUS BETA which can use more constellations?
Make sure your ARP is correct. (From point of interest up to bottom of RS3). The OPUS calibration file will take into consideration the additional distance to APC (from ARP to APC) as long as u selected RS3 of course.
If I understand correctly, you want to collect GCPs using OPUS PPP. With this method, you won’t need to set up rover and base outputs. All you need to do is collect the log data with good satellite visibility. We also have this OPUS preset available to ensure the log meets OPUS requirements. Please give it a try, and if the issue persists, I’ll need to check the data quality.
Please share the log, and I’ll take a closer look. If you’d prefer to share it privately, you can email it to support@emlid.com and mention this thread.
