Screwed up Traverse; Need help editing raw data to recover

I am not real good at editing raw files, but you should save the original, in another name. Maybe even print it. Then, after printing it, make your changes carefully. What software do you use? It's been a while since I have done this sort of thing. I don't want to risk "helping" you. But, those are reasonable tips.

N

> I am not real good at editing raw files, but you should save the original, in another name. Maybe even print it. Then, after printing it, make your changes carefully. What software do you use? It's been a while since I have done this sort of thing. I don't want to risk "helping" you. But, those are reasonable tips.
>
> N
Thanks. I recovered the .rw5 file and I now have backups upon backups. I can edit to my heart's content (assuming I can figure out what to edit), without fear of losing what field data I have. I'm using TraversePC. I have a conference set up with them tonight to see if we can discover the error there and make changes there, and forget about the raw data.

I just always thought that whether with TPC, Carlson/ACAD, or any other office software, that you have to make sure the raw data from the DC is correct; that you need to correct errors from the field straight away, but I really don't know this for a fact, and perhaps office guys are mopping up after sloppy field work all the time. Not sure who they blame if it's a one man operation, lol.

I think I'm going to start by weeding out all the "side shot" data to the points off the traverse...Those are Horizontal Angles of about 90 degrees or so. Then see what's left of the traverse.

My strongest comment will be: carefully sequence things. IF you print it out, and then go mentally through it all, with a stake out, just sequencing stuff, you will likely find a wrong backsite point, or inst point.

Those things are MEANT to be comprehended like the Bible. Line upon line, and precept upon precept.

N

draw all sideshots on one layer, and all traverses on another.

You could just compute the traverse manually using your field notes and raw data using a cogo routine. Going through the data and manually computing your traverse would be good practice for you and give you a better feel for what to do, not to do next time. Don't worry about the side shots, that is until you realize one of your side shots was actually a traverse shot. 😉

Surveying in of itself isn't rocket science. Geodesy, maybe. The real challenge is being able to figure out exactly where things got all goobered up and making everything right again with world.

> You could just compute the traverse manually using your field notes and raw data using a cogo routine.

Thanks for the advice Williwaw. Unfortunately the comment I made about not using a field book just because one uses a data collector was apparently not clear enough:

My notes SUCK! They don't tell me anything. Of course 308 comes after 307 and 307 comes after 306. What's to write down?
Even my notes on the DC leave a lot to be desired: "DEEP WOODS"...Ya, that's informative. NOT! It was all deep woods.

This Grasshopper learned a lesson on this outing.

Back to basics grasshopper. Good field notes with occupying points, backsighting points, foresights, good concise descriptions, diagrams. Your notes should be clear enough someone else could figure out exactly what you did. If you can't figure it out, nobody can help you. Don't fall for the 'magic box' data collector mindset. If your seriously trying to learn how to do this stuff you should doing it all long hand with a calculator, booking all your angles and distances. Master that first. And it ALL begins with good notes.

First thing I noticed is, you are traversing with azimuths and not angle right.

Would that make a difference?

And, your first BS check looks a little funny...

BK,OP307,BP305,BS45.4822,BC45.4822
BD,OP307,FP305,AR45.4822,ZE98.0349,SD182.737000,--SKIDDER TRAIL
--Calculated: AR45°48'22", HD271.908, Z1199.030
--Measured: AR45°48'22", HD180.930, Z1233.758
--Delta: AR0°00'00", HD-90.978, Z34.728

> First thing I noticed is, you are traversing with azimuths and not angle right.
> Would that make a difference?
I've been "set backlight to BS Azimuth" in SurvCE, carrying the Azimuth from the beginning of the traverse. That part seems to work fine for me. The angles still measure to the right though, and I think SurvCE calcs the new BS Azimuth.
>
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> And, your first BS check looks a little funny...
>
> BK,OP307,BP305,BS45.4822,BC45.4822
> BD,OP307,FP305,AR45.4822,ZE98.0349,SD182.737000,--SKIDDER TRAIL
> --Calculated: AR45°48'22", HD271.908, Z1199.030
> --Measured: AR45°48'22", HD180.930, Z1233.758
> --Delta: AR0°00'00", HD-90.978, Z34.728

But I think you're onto something here. How can my Foresight Point in this record be 305, if it's also the Backlight Point?! The Delta of 90.978' seems close to what I'm missing. I'm at work now, but will try dumping this record when I get home tonight. I think I did the set again after I realized I might have started by measuring the next set's Backsight with the gun still flipped to "Reverse".

I haven't found a way to delete observations on the fly in SurvCE, like when I've obviously made an error. Perhaps the software is designed that way...record everything; blunders and all, and deal with it later, rather than give crews the ability to edit what they've measured. Thanks.

I suggest that you make a little drawing of all TRAVERSE and control points, as you do your field work.

Until you really get proficient with this game.

N

> I suggest that you make a little drawing of all TRAVERSE and control points, as you do your field work.
>
> Until you really get proficient with this game.
>
> N

I have been drawing sketches in the field book, while using the DC, but that's about all, and to respond to Williwaw's comment: I did do it all by hand, completely, last summer.

I just was moving too fast, clicking away on the thing, and did not notice the populated fields for BS and OP; noting that the instrument is in direct or reverse face, etc. Taking the time to record more data...like even only the SD and angle or azimuth to the next point, would have probably slowed me down enough to look more carefully at each screen. Plus, it would be handy to compare with the Back sight information that comes up AT the next point.

I think this is about developing methodical habits...mental check lists at each setup. I might think about sitting down and writing a physical check list to use at each setup. Heck, pilots do it...even those who've flown for years.

A good sketch in addition to your notes forces you to slow down and think in detail about what you're doing.

I wasn't sure about the "AR" code for azimuths, but it does seem to be calculating angles correctly.
The "BP" and "FP" codes are correct on the backsight check. It is backsighting the BP and then checking it as a FP.
With the large deviation in the backsight, either the coordinates are wrong for the occupy/backsight or both OR you occupied the wrong point.

Changing the coordinates and azimuth might be the key, or changing the incorrect point number and then re-running the numbers.

> I wasn't sure about the "AR" code for azimuths, but it does seem to be calculating angles correctly.
> The "BP" and "FP" codes are correct on the backsight check. It is backsighting the BP and then checking it as a FP.
> With the large deviation in the backsight, either the coordinates are wrong for the occupy/backsight or both OR you occupied the wrong point.
>
> Changing the coordinates and azimuth might be the key, or changing the incorrect point number and then re-running the numbers.

Well I think I know generally what happened but have not yet corrected the errors; your suspicion is probably correct:

Day one...Open new job in SurvCE; call it "Job 1"
Day two...Open "Job 1" and continue the traverse, starting with last fore sighted point and backsighting to last point setup upon from the previous day.
Day three...Following different advice, Create New Job ("Job 2"), in SurvCE, but use the last two points from the "Job 1" traverse, (all the points of which I'd added to the "Control File", and were now available in "Job 2", and continued on the traverse.

Bottom line: Either on Day two or Day 3, I set upon one point, but SurvCE identified it as another point. In effect, Either I used the same point number twice for two different places on the earth, or I set upon the same place on the earth twice, and SurvCE called it two different point numbers. (Notice how my language is beginning to blame SurvCE, rather than the grasshopper pushing the buttons?)

Now I just have to methodically go back through the data, point by point finding out where it went south (or should I say southwest?):-S

Until they finish development on that brain implant to link us directly to our data collectors and office software, we will continue to see this. They consistently do what we tell them rather than what we thought we told them. 😛