You’re workflow is vastly different than typical GNSS use, but I understand where you’re coming from. I didn’t get the “2 shots per point”? With the rover on 5Hz we are actually taking 75 observations in 15 seconds. Primary control off the benchmarks are 1 minute and 300 observations then level-looped.
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That’s fine if it works for your projects. My attitude has always been “prove me wrong”. If there is a questionable issue, I’ve got the data to backup my position. Usually others don’t. I’ve proved many other surveyors positions wrong that they’ve located in high multi-path areas with GNSS. They usually claim it was a “fixed” position. Reviewing the data they provide is usually less than 1 minute with no re-occupaton of the point.
I’ve been using GPS/GNSS receivers since late 80’s using all brands. Time on station is important to get a confident position. I don’t care about a “fixed” solution unless you’ve got the data to back it up. Enough said.
Works pretty good if you can verify stakeout at 1.5-2cm with an instrument.
People that don’t log even while running RTK are asking for it.
Let’s clarify for everyone that this is primary survey control and boundaries. Most people that “survey” today have no need for this level of accuracy. Even though we have an inhouse 2cm threshold on our primary control our construction layout tolerance is 3cm which is very easy to obtain even with 5 second observations. If you do your proper backsights and spot checks then there is no need to reoccupy every point in the day-to-day workflow.
Pretty impressive considering RTK wasn’t even developed and released until 1992-93, but that’s a statement for the 80’s when all we had was a smattering of satellites and L1. Everything was PPK in 2000 when I started and all control was still manual total stations with HP48’s. The days of the three-man crew are gone unless your banging bluetops.
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As far as receivers available during the late 80’s, I think you need to do some research. Our firm was one of two that used Trimble receivers available at the time in SC. Our first project which paid for the receivers (3 @ $27k each) was providing 60 first order ( exceeding 1: 500,000) control points for photogrammetric control and many of the points were included in the NSRS.
Accuracy standards in SC have various levels of accuracy for different survey projects. Our boundary surveys locating property corners have accuracies of less than <3 cm. Our surveys will be and have been a standard for others to follow in the future.
Confidence in locating a point is basically set to the user, many have the knowledge in statistics and GNSS use, others don’t or are newcomers trying to learn. Getting in a hurried situation to locate points as fast as you can, willl get you in trouble.
I’m just here for advising users because of my experience. If you don’t think you need it, ignore my posts. Everybody wants to be a Land Surveyor, but don’t want the trouble or hassle of being licensed.
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As i understand, it comes down which of these three problems you would have the least of.
Time, Cost or Error.
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Or maybe “Time, Cost, and Cost of Error” 
Haha good one. I should have added the fourth one.
But I guess its implied (Error = trouble)
Hi Tatiana,
Thank you for your support so far 
Just following up from a previous post I made.
Can you share with us some of the details about how the RS2 determines a fix eg.
- number of iterations performed
- quality determinant eg. fixed result is 3 standard deviations better than the next best result
- if the software assesses for linear trends in the coordinates of a point
It would be nice if a minimum number of satellites could be set.
Also a minimum length of time that corrections have been received without interruption?
Kind regards,
James
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Can something like this be implemented?
I do not know the fine details of the Surefix system, however they often state that they guarantee a fix is true 99.99% of the time.
This feature will get a lot of Surveyors excited.
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Using 2 RS2. 1 base 1 rover. The errors are random. You get fLse fixes in both open and high building areas. This is my problem. I understand that you would get false fix in building areas but in open areas? There was 1 case where it was a fix status for nearly 30 secs. I pressed the accept button and after pt was saved status went float. When I reviewed the point it was recorded as a float.
@jjb I´m having some false fixes too with Ntrip. I thought that it may be related to NTRIP and that my baseline is 53km. And that using 2 equal antennas and shorter distances the results would be better, but if you are getting false fixes in open areas with 2 RS2, maybe it’s related to the RS2 itself.
One thing I have found helpful using FieldGenius for Android is the ability to set tolerances for the PDOP and Age of Correction. I turned these down to a PDOP of 5 and Age of 2 seconds and very rarely if ever get a false fix as verified by also PPK’ing the logs. I don’t think Reachview has such an ability?
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I don’t think that an age of correction of 2 seconds prompts a false fix,. The atmosphere simply doesn’t change that quickly. However, a PDOP of 5 would most certainly be a candidate.
But overall I am a fan of more indication of the risk of a false fix. Calculating that risk shouldn’t rocket science. One could include GDOP or RDOP (if in survey mode), cycle slips or minute, average SNR, and AR ratio over that last minute… (and probably more that I didn’t think of)
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Average SnR would be a great addition. Like in Reachview you can establish an acceptable SnR value, but in FieldGenius you can also determine how many satellites that meet that criteria are available for each specified category of shot. We have standard topo, layout and control. Control is the 5/2 setting, but also requires 12 satellites whereas topo requires 7 and layout 9. Topo also only requires a PDOP of 10.
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Where in Fieldgenius do I set that up?
On the first screen after you connect to the receiver at the bottom you choose what kind of shot it is period put it on control and you can edit the settings.
Totally agree.
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