I like StarNet if I have to combine data from totally different systems, or on the rare occasion I need to de-weight or heavily modify standard errors for a single observation. But if I'm doing the latter it usually means I'm in Hail Mary territory already.
I'm not a big fan of its outlier trapping, just using the arbitrary value of 3 for flagging standardized residuals. TBC computes and uses the Tau criterion, which is more rigorous and minimizes the chance that the operator will toss a good observation. Side-by-side
If my data can go into TBC or StarNET, TBC is way faster for QC, blunder trapping and the adjustment. Viewing and selecting data in the plan view is very easy. Not to mention I can process baselines, pull in NGS data sheets and CORS data, etc. TBC also handles geoids and fixing ortho elevations better.
All that being said, StarNET is still an awesome, powerful program. We have both TBC and StarNET and we wouldn't want to give up either.
After a couple of months, I learned that the actual adjustments weren't?ÿ as valuable as its ability to quickly isolate errors, correctly combine various types of survey data, and provide a template in which I can describe the fieldwork.?ÿ
Very well said. Except that the word "errors" should be replaced with "blunders".?ÿ
If my data can go into TBC or StarNET, TBC is way faster ...
That's a major thing. StarNet accepts data from a wide variety of collection programs. I've not used TBC, but I expect that it is restricted to Trimble format data.?ÿ?ÿ
@mark-mayer I have done a couple of traverses with civil 3d (compass rule adjustment) but have found it is almost easier to do it by hand.
@rover83 TBC is great for blunders and outliers even before you get into the adjustment. Those red flags scare the heck out of some but I see them for what they are just a little flag that sais check me out I might cause you some heartache. Most of them for me are not even dealt with as they are usually a vertical angle from measured rounds to some point so close to the gun it doesn??t make a difference. But When you can go through a 40 acre topo and find a vertical bust in just a few moments from just going through and glancing the software has paid its way for sure. The more I use it the more I love it.?ÿ
I hate to say it but it is most definitely up there with StarNet and I loved that program. But Rtk robot resections mini traverses within a site all on one screen is priceless. And I honestly have been trying to break it on purpose. I have had some crazy looking networks from multiple crews tying to each other from all sorts of ways. I went out today as I was uncomfortable with one side that veered off i to know-mans land from the main traverse and did some ground proofing across the site to my adjustment and it was better than I expected and fell within what TBC said it would. So i called it a day.?ÿ
I ditto TBC for adjustments. I was a heavy StarNet user but in 2018 I had a traverse with hundreds of setups and TBC made finding bad angle sets very easy (I have a minimum of 4 sets and sometimes more because I hit set + in the field when I have a loose set). TBC has greatly improved over the past several years.
I view LSA as a processing tool that allows you to use all of your measurements to derive the best coordinates for a given point. The other way is use whichever measurement happens to be first for a coordinate and the rest for a check, that is kind of arbitrary. The measurements aren??t being adjusted so much as being fit together with minimized changes.
If my data can go into TBC or StarNET, TBC is way faster ...
That's a major thing. StarNet accepts data from a wide variety of collection programs. I've not used TBC, but I expect that it is restricted to Trimble format data.?ÿ?ÿ
Not exactly true.?ÿ I know TBC wil at least accept data from Leica and I think Topcon Levels, and can also do Static GPS networks with pretty much anything if converted to RINEX.
Still not sure about other total stations as I haven't had the opportunity to try any since we got TBC and haven't really had the time to look.?ÿ
I'm also fairly sure it will work with other types of scanners.?ÿ
I know TBC wil at least accept data from Leica and I think Topcon Levels...Still not sure about other total stations
If there's an easy way to get SurvCE data into TBC, I haven't found it yet, so Star*Net is still my go-to when TS data is involved.?ÿ For pure GNSS networks I'll sometimes adjust in TBC, but other times I'll run it through Star*Net because I'm just more comfortable with it.
For normal, standard stuff i don't get you guys still use an adjustment routine in the office. I see all on my data collector and it gives immediate errors. If the error is too big i cannot continu.
The error you eliminate (a few mm's) by adjusting is immediate back by not holding your rod completely level for detail points.
Also with resection routines and rtk gnss for setup points, who still does it the old fashioned way? All is mentioned in the field.
I just import my xyz list with coding in my survey package and continu drafting.
@beuckie?ÿ
Not all field personnel have the same skill level as you.
I'd be fine with you running a DC adjustment on a one off project that you took lead on.?ÿ However, if it was a larger project involving multiple crews with differing equipment, I would not want a variety of adjustments and reports.?ÿ?ÿ
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@murphy That is right on point. ?ÿSkill level and how many different people and equipment on a job and what is the job scope. Or requirements. That dictates what needs to be done. If you are doing some topo in the woods or rough terrain it is not as important as where the topo is done when it is tying into the existing curb and gutter or roadway intersections. Have a site right now with some old buildings that will be demolished I don??t sweat the location very much because it is being removed. Where I tie into existing roads and drainage pipes etc I want those to be spot on for design to match so I am not back out trying to field adjust when staking out in the future. Not everyone that surveys just automatically knows all of this. Thats why mentoring is important and explaining when we are building a watch and when we are not to those under our care. Topo is not always just a topo it depends on why and what is going to be done after that becomes important on how to approach the job.?ÿ
You said it correctly for sure.?ÿ
Wholeheartedly agree.
I don't know of any field collection software that runs LSA, outlier detection or blunder trapping for multiple days of fieldwork across different crews.
It's pretty common for us to have GNSS NRTK vectors that can have up to 3-5cm of error in H/V, total station observations that are more on the order of 3-5mm, and level observations that are more like 1mm or less. Our primary link to the NSRS is through the RTN stations and NRTK vectors, but we have higher-quality terrestrial data that needs to be properly weighted. If we're running base/rover, we're likely going to need to post-process to get an updated base location anyways.
?ÿ
The bottom line is, analyzing data and adjusting final positions is best practices and gets you the best quality data, and is not a high bar to clear with today's computing power and multitude of available software suites. If field data is not rife with errors and mis-labelled points, I can crank through the QC and network adjustment in an hour (sometimes way less, as in 5-10 minutes) for a basic control network plus observed monuments.
It's also required on certain projects to ensure you have done your due diligence and meet minimum standards. ALTA/NSPS (and boundary work here in WA) have minimum relative accuracy standards. While I may have a pretty good rough idea of how good the work is, I'm not stamping that survey until I know for sure that certification is correct and I do meet those relative accuracy standards - which means running LSA and getting those error ellipses, because without them we can't know for sure whether we meet standards..
Most of the complaints and scoffing about LSA, at least within my own firm, come from folks who are ignorant of what it is and what it does, or from folks who are not technically competent plus insecure about using post-processing software.
Wholeheartedly agree.
I don't know of any field collection software that runs LSA, outlier detection or blunder trapping for multiple days of fieldwork across different crews.
It's pretty common for us to have GNSS NRTK vectors that can have up to 3-5cm of error in H/V, total station observations that are more on the order of 3-5mm, and level observations that are more like 1mm or less. Our primary link to the NSRS is through the RTN stations and NRTK vectors, but we have higher-quality terrestrial data that needs to be properly weighted. If we're running base/rover, we're likely going to need to post-process to get an updated base location anyways.
?ÿ
The bottom line is, analyzing data and adjusting final positions is best practices and gets you the best quality data, and is not a high bar to clear with today's computing power and multitude of available software suites. If field data is not rife with errors and mis-labelled points, I can crank through the QC and network adjustment in an hour (sometimes way less, as in 5-10 minutes) for a basic control network plus observed monuments.
It's also required on certain projects to ensure you have done your due diligence and meet minimum standards. ALTA/NSPS (and boundary work here in WA) have minimum relative accuracy standards. While I may have a pretty good rough idea of how good the work is, I'm not stamping that survey until I know for sure that certification is correct and I do meet those relative accuracy standards - which means running LSA and getting those error ellipses, because without them we can't know for sure whether we meet standards..
Most of the complaints and scoffing about LSA, at least within my own firm, come from folks who are ignorant of what it is and what it does, or from folks who are not technically competent plus insecure about using post-processing software.
I went out with another crew. They worked together and I worked by myself. 2 days of Topo. TS & RTK. The night before going home I said drop by my hotel room and I??ll show you how to process it in TBC. 5 minutes, drop the files in there, complete report, error ellipses, etc. Linework too.
I went out with another crew. They worked together and I worked by myself. 2 days of Topo. TS & RTK. The night before going home I said drop by my hotel room and I??ll show you how to process it in TBC. 5 minutes, drop the files in there, complete report, error ellipses, etc. Linework too.
No kidding, it is ultra fast when you have good field procedures.
I've always found that the problems only start when the processor doesn't understand the TBC computation engine and/or doesn't understand error propagation and LSA. Throw a couple of minor field blunders in there and processing time will go from a few minutes to several hours, or sometimes I've seen folks just totally freeze up and not be able to troubleshoot the network.
No software can completely overcome ignorance or inexperience, willful or otherwise...
@beuckie?ÿ
I can't agree more with this.?ÿ
It's standard practice for us to set out control now with RTK, occupy the control with a robot and do one or at most two point traverses between control points and check in.?ÿ
The world has changed, adjusting out that .02' or the 5mm "error" is pointless for most tasks I do. If the error shows up large, then it's time to resurvey.?ÿ
