Larry Scott, post: 455213, member: 8766 wrote: It was an ongoing project, so it was checked. If not, the adjusted value would stand.
Hopefully you don't do alot of worrying about tenths of a foot do you? Hopefully I do. High precision work returns higher fee. And steel fabrication has to fit. That's not elitist. Stake a rail yard switch, or bridge span, off a tenth and see what happens. With a properly configured network, AND with LS adjustment there's no worrying about 0.10'. That's the point!
You're in a different world. I use to do high steel layout with an old Hilger Watts Theodolite and 100 foot chain. We didn't have a LS adjustment program or even a calculator. The old guy I worked with knew all the tricks of the layout trade. I don't know how many times he said "Close enough we're not building a watch," It still amazes be how an iron worker that can't read anything but fabrication drawings can lay it all out with on old Carpenters tape and everything fits perfect. I've watched railroad crews lay track. It's hard to believe a tenth matters to them. They usually use a chunk of rope to layout tracks. You must be working on high speed rails. First train that goes over the tracks moves them three or four inches.
Yep I never chatted with one of you Elitist before. Patooh!
Skeeter1996, post: 455219, member: 9224 wrote: You're in a different world. I use to do high steel layout with an old Hilger Watts Theodolite and 100 foot chain. We didn't have a LS adjustment program or even a calculator. The old guy I worked with knew all the tricks of the layout trade. I don't know how many times he said "Close enough we're not building a watch," It still amazes be how an iron worker that can't read anything but fabrication drawings can lay it all out with on old Carpenters tape and everything fits perfect. I've watched railroad crews lay track. It's hard to believe a tenth matters to them. They usually use a chunk of rope to layout tracks. You must be working on high speed rails. First train that goes over the tracks moves them three or four inches.
Yep I never chatted with one of you Elitist before. Patooh!
By the way my old boss drank himself to death. I guess he was worrying about those tenths he was off.
Skeeter1996, post: 455219, member: 9224 wrote: You're in a different world. I use to do high steel layout with an old Hilger Watts Theodolite and 100 foot chain. We didn't have a LS adjustment program or even a calculator. The old guy I worked with knew all the tricks of the layout trade. I don't know how many times he said "Close enough we're not building a watch," It still amazes be how an iron worker that can't read anything but fabrication drawings can lay it all out with on old Carpenters tape and everything fits perfect. I've watched railroad crews lay track. It's hard to believe a tenth matters to them. They usually use a chunk of rope to layout tracks. You must be working on high speed rails. First train that goes over the tracks moves them three or four inches.
Yep I never chatted with one of you Elitist before. Patooh!
I never chatted with someone that didn't care about best practices.
Larry Scott, post: 455203, member: 8766 wrote: For LS to be meaningful, its application is suited to properly configured and weighted networks. A traverse, absent redundancy, LS isn't beneficial.
How about a recent example... Establishing control on 22 ac site. Initial survey was a perimeter traverse, 4 inter visible corners, with a satisfactory closure. 0.05 ft. As the project progressed 6 additional control points were established and a complex network resulted. However, the network returned a significant distance error factor. One of the distances, from the initial boundary, returned a residual far greater than any other. So to your question: use the LS adjusted value? The initial traverse looked good. That one (1000 ft) distance was remeasured and was found to be 0.10' shorter. (Slope distance mistaken for horizontal distance.) The LS adjustment isolated the error, not smearing the error around. The adjusted value was in fact correct.
Is that elitist? I'll let you decide.
These kind of discussions always take me back to College and my experiences with him. You could carry your calculations out to ten thousands. Turns it in and he would give you a D because you failed to observe the significant figures. It's like arguing with Flood Plain Administers. They're dealing with a BFE that was derived using 40 foot contour maps, a digitized watershed boundary, a statistical computer model, and they're interpolating the BFE down to a hundredth of a foot. Not knowing the quality of your equipment, your layout configuration, and your measuring routine. You maybe kidding yourself about obtaining one tenth accuracy.
Skeeter1996, post: 455223, member: 9224 wrote: These kind of discussions always take me back to College and my experiences with him. You could carry your calculations out to ten thousands. Turns it in and he would give you a D because you failed to observe the significant figures. It's like arguing with Flood Plain Administers. They're dealing with a BFE that was derived using 40 foot contour maps, a digitized watershed boundary, a statistical computer model, and they're interpolating the BFE down to a hundredth of a foot. Not knowing the quality of your equipment, your layout configuration, and your measuring routine. You maybe kidding yourself about obtaining one tenth accuracy.
As YOU said: "in this day and age, with modern equipment." A whole lot of country was built with transit and chain at 1:10,000. Okay, how does that apply?
And a proper LS adjustment doesn't involve more field work. And, of course, what's the job specs? What's the liability? Why not?
Skeeter1996, post: 455223, member: 9224 wrote: These kind of discussions always take me back to College and my experiences with him. You could carry your calculations out to ten thousands. Turns it in and he would give you a D because you failed to observe the significant figures. It's like arguing with Flood Plain Administers. They're dealing with a BFE that was derived using 40 foot contour maps, a digitized watershed boundary, a statistical computer model, and they're interpolating the BFE down to a hundredth of a foot. Not knowing the quality of your equipment, your layout configuration, and your measuring routine. You maybe kidding yourself about obtaining one tenth accuracy.
Someone asked me "how often do you check tribrach? 2-3 times a year?"
Rotating calumniator. Check the tribrach at every setup, why not? In this day and age.
Larry Scott, post: 455224, member: 8766 wrote: As YOU said: "in this day and age, with modern equipment." A whole lot of country was built with transit and chain at 1:10,000. Okay, how does that apply?
And a proper LS adjustment doesn't involve more field work. And, of course, what's the job specs? What's the liability? Why not?
Yes it was and LS never arrived until I'm guessing the later 50's. Just guessing. I never became aware of it till the 70's. I simply don't think it's worth the effort. The old surveying Technics required alot of blunder detection because of the greater amount of human interaction. The Japanese have taken that human element almost entirely out of surveying with total stations and robotic stations. We use to calibrate chains before every job. You probably calibrate your TS every couple of months. I stand behind my statement "In this day and age" if a LS Adjustment makes you feel good do it, but I don't see a significant advantage to doing one on every survey. In steel layout we never had intricate control networks. We worked off existing structures. Just like you do in property surveying. I just don't see where they provide a significant benefit.
I
Larry Scott, post: 455226, member: 8766 wrote: Someone asked me "how often do you check tribrach? 2-3 times a year?"
Rotating calumniator. Check the tribrach at every setup, why not? In this day and age.
I don't even know what a rotating calumniator is, let alone how to check one. How do you check a tribrach when there's a D8 idling behind you waiting to go to work?
Skeeter1996, post: 455234, member: 9224 wrote: I
I don't even know what a rotating calumniator is, let alone how to check one. How do you check a tribrach when there's a D8 idling behind you waiting to go to work?
That reminds me of another old saying my old boss use to spout."Design it to a hundredth, stake it to a tenth and build it with a D9 Cat". The man was a Legend in his own mind.
Larry Scott, post: 455226, member: 8766 wrote: calumniator
Collimator?
Bill93, post: 455237, member: 87 wrote: Collimator?
Spell Checker Police! Good job.
This thread has turned into a trip for sure. I was waiting with anticipation for Loyal's description of LDP's as they apply to measurements in the Rockies but that never unfolded. Then it took a spur into LSA's and how they relate to boundary resolution. I waited to see how that would unfold as the example provided for their usefulness seemed relevant but again I was disappointed as that topic degraded to construction staking and steel/building layout. Further to my dismay it has eroded into daily equipment calibration and the correct use of spelling and vernacular. How far we have come as "professionals"!!!!
Skeeter, the original phrase as I heard it is "measure it with a micrometer, mark it with a crayon, chop it with an axe!"
g'night gents
Cameron Watson PLS, post: 455242, member: 11407 wrote: This thread has turned into a trip for sure. I was waiting with anticipation for Loyal's description of LDP's as they apply to measurements in the Rockies but that never unfolded. Then it took a spur into LSA's and how they relate to boundary resolution. I waited to see how that would unfold as the example provided for their usefulness seemed relevant but again I was disappointed as that topic degraded to construction staking and steel/building layout. Further to my dismay it has eroded into daily equipment calibration and the correct use of spelling and vernacular. How far we have come as "professionals"!!!!
Skeeter, the original phrase as I heard it is "measure it with a micrometer, mark it with a crayon, chop it with an axe!"
g'night gents
You could use the "way back" machine to review the old POB posts about LDP's. There was always quite a debate going on there and Loyal put out a LOT of good info there. It's probably tough to keep trying to explain it.
Skeeter, this is quite the thread, I can see you are really into calibrating to old data, I do think it burned you a bit this time. But as long as you can find the bad data, carry on. 😎
Cameron Watson PLS, post: 455242, member: 11407 wrote: This thread has turned into a trip for sure. I was waiting with anticipation for Loyal's description of LDP's as they apply to measurements in the Rockies but that never unfolded. Then it took a spur into LSA's and how they relate to boundary resolution. I waited to see how that would unfold as the example provided for their usefulness seemed relevant but again I was disappointed as that topic degraded to construction staking and steel/building layout. Further to my dismay it has eroded into daily equipment calibration and the correct use of spelling and vernacular. How far we have come as "professionals"!!!!
Skeeter, the original phrase as I heard it is "measure it with a micrometer, mark it with a crayon, chop it with an axe!"
g'night gents
Yes, for sure. I feel like I'm chasing my tail.Yours is for building structures, mine was a road builders axiom. There's one about it's hard to remember our initial goal was to drain the swamp, when we're knee deep in snakes. Or something like that..
MightyMoe, post: 455267, member: 700 wrote: Skeeter, this is quite the thread, I can see you are really into calibrating to old data, I do think it burned you a bit this time. But as long as you can find the bad data, carry on. 😎
Old data puts you into the footsteps of the previous Surveyor. Unfortunately I do find an awful lot of bad data. I wonder how many of them we're LSA their data. What bit me this time was my memory. A couple of posters steered me right quite early, but then the anti site calibration group jumped on me and then the LDP group came after me, and the the LSA group came after me and here we end up chopping with an axe. I kind of get the feel of what Trump is going through on a much smaller field of course. Now the Democrats will be after me.
I was a little disappointed Loyal faded off before we got to the meat of LDP. He had my attention there for awhile.
Skeeter1996, post: 455289, member: 9224 wrote: Old data puts you into the footsteps of the previous Surveyor. Unfortunately I do find an awful lot of bad data. I wonder how many of them we're LSA their data. What bit me this time was my memory. A couple of posters steered me right quite early, but then the anti site calibration group jumped on me and then the LDP group came after me, and the the LSA group came after me and here we end up chopping with an axe. I kind of get the feel of what Trump is going through on a much smaller field of course. Now the Democrats will be after me.
I was a little disappointed Loyal faded off before we got to the meat of LDP. He had my attention there for awhile.
If you are using TBC, then LDP creation is right there under project settings/Coordinate System/Change/Default projection (Tranverse Mercator). Click on it and it will basically give you a slide that allows you to set-up your LDP. It's easy, a couple of minutes, all you really need to know is where your site (lat, long) is, and then play with the scale factor to get your PPM's down for the elevation of your site (hint 1 will not work). In Montana, I highly recommend it. Montana SP is a PITA.
I imagine Loyal is busy, and teaching LDP's isn't all that simple over a site like this one.
Bill93, post: 455237, member: 87 wrote: Collimator?
Damn spell auto complete
Skeeter1996, post: 455289, member: 9224 wrote: Old data puts you into the footsteps of the previous Surveyor. Unfortunately I do find an awful lot of bad data. I wonder how many of them we're LSA their data. What bit me this time was my memory. A couple of posters steered me right quite early, but then the anti site calibration group jumped on me and then the LDP group came after me, and the the LSA group came after me and here we end up chopping with an axe. I kind of get the feel of what Trump is going through on a much smaller field of course. Now the Democrats will be after me.
I was a little disappointed Loyal faded off before we got to the meat of LDP. He had my attention there for awhile.
Skeeter,
Sorry for "dropping out" on the LDP issue. I am swamped with work right now, and have been for most of this year. To "properly" outline [even] the basics of LDPs, requires a lot of work, and really needs examples and exhibits that also require significant time.
I would suggest that you take a look at Shawn Billing's articles in American Surveyor a couple of years back:
http://www.amerisurv.com/PDF/TheAmericanSurveyor_Billings-GroundVersusGrid-LDPpart1_Vol10No9.pdf
http://www.amerisurv.com/PDF/TheAmericanSurveyor_Billings-GroundVersusGrid-LDPpart2_Vol10No10.pdf
You will no doubt have some specific questions once you digest the above articles, and a new tread will be the best way for you to get good answers to those questions.
Loyal
Larry Scott, post: 455293, member: 8766 wrote: Damn spell auto complete
Wasn't that the "encanabulator"?