Verifiable State Plane Coordinates, Blunder detection, and other questions

Hello all, thanks for adding me to this group. I just purchased 4 Reach RS + units and have some questions from a party that I am working with. Any help would be appreciated. Here are the questions: "Our main concern is post-processing the Emlid GPS Data in order to get correct, verifiable State Plane Coordinates with sub-centimeter accuracy as we do with the Trimble Equipment.
Specifically a step-by-step “Emlid Photo Control for Dummies”:

Pre-processing and field - Which files to use, where are they downloaded from and what they represent

Processing and what each of the user-specified settings and how they affect results and accuracy

Blunder detection and avoidance in the field and in the office

I’m familiar with dual frequency Trimble and Leica units, but this Emlid equipment is completely new to me and it seems to have little in the way of error flagging.
In the videos I’ve watched, the people are entering a coordinate which I believe they pull from their BASE, which I believe comes from an off-site reference station that broadcasts the correction and that is how they get their sub-centimeter accuracy (Emlid files got kicked back from OPUS because it’s single frequency). The creators of those videos live in more populated areas and have the luxury of those base stations, but I’m not sure if Pinedale Wyoming is close enough to use those."

well i think most folks here do their post processing with RTKIB but it sounds like you may have access to other desktop software (TBC? pathfinder office) so you may want to see if you can use your existing desktop software to post proccess. especially since RTKLIB and the Reach receivers will not give you state plane out of the box. and in my opinion if you want sub centimeter you should use a total station not RTK. im sure some day a GNSS receiver marketing department is going to claim “sub gnat’s ass accuracy!”

yeah this may not be the tool set your looking for.

yes that would be network RTK over a cellular network. if you are outside the network then you have nothing. so you will need to get your base coordinates from other means. some folks use PPP others RTKLIB with CORS, i use a separate set of l1/l2 receivers and do OPUS.

allot of this is covered in Emlids online docs which are really rather good.

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Thank you for the reply!

also you may want to look into the threads here about third party survey apps like fieldgenius.

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Even trimble gear will have the constraints of physics, and thus will be within the usual 2-3 cm absolute accuracy. There marketing might want to claim otherwise, but nope.

Have you gone through this one: https://docs.emlid.com/reach/common/tutorials/gps-post-processing/ ?

This will get you started: http://www.rtklib.com/prog/manual_2.4.2.pdf

RTK is the same technique working with single or multiple frequencies. All the fundamentals are the same.
What you need to know is that on L1:

  • Observation times are a bit longer, depending on your needs.
  • Time-to-first-fix are longer
  • More sensitive to sky-obstruction and multi-path situations.

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