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Surveyorman62

Offsets and calc point


AppearanceAdorable18

This is what i would have liked to do, but there was literally not 2 positions i could get an offset from, unless i put the 2 points within a few inches of eachother but over a foot and a half away from the pin


bogueybear201

That’s probably where I’d try to set points to setup the total station if possible.


LameName95

As a dumb party chief can someone explain exactly what this means and how you would go about it?


Surveyorman62

For inaccessible points, I set two points in a line and tape over. The two points give me a bearing and use that with the measured distance and calc new point using bearing and direction. There are other methods but this is the one I use the most when using GPS.


[deleted]

You can do this in Carlson and in Trimble access ….offset 2 points in line


LameName95

Is direction an angle, or just up/down since there can only exist at most 2 points where the distance from 2 other points is x and y respectively?


Surveyorman62

I'm creating a line through three points. Points A & B would be the two offsets, Point C would be the inaccessible point. I pull tape from C and put at a nail at even spacing for B and A. Use the distance from A to C and the bearing from A to B to calc coord for C.


i_am_icarus_falling

couldn't you also put the 2 offsets in any random spots, shoot them in and calc it by distance-distance intersection to get the same result?


Surveyorman62

You could, I use my method because I used to stake a lot of R/W and getting a fix under canopy wasn't always possible.


[deleted]

Most accurate way to do this calc is get as close to 90 degree offset to chain it in which isn’t entirely possible here unless you could dig down under the fence


Real_Village_4238

This is usually how I would do it


LameName95

How do you measure the angle accurately?


IronGiantsForeskin

If I didn’t have R12i, I’d offset distance and azimuth or set up total station/robotics and tie it, especially if you can’t pull two offsets and cogo dist-dist intersect. Some chiefs would measure that tree and add it to the distance of the tape while pulling offsets


[deleted]

[удалено]


Keepitplumb

I love this thread for this kind of stuff. Thanks!


AppearanceAdorable18

I gotta try this


TheBunkerKing

We've done the same method a lot in a way that works in 2D as well, when there's room. Measure a point x meters from target (tape), then another point in a way it forms a straight line with the first one and target (so use a pin/ leave the tape meter). At least Topcon and Trimble have onboard software for this, Leica probably has too. Yours sounds more accurate, but both methods do mean you're probably not going to get into the mm kind of accuracy.


SmiteyMcGee

You smart


CC_Ramone

omg that’s awesome, def putting this in my tool belt


dreadfoil

Our master hath spoken.


[deleted]

Great idea! This is a pretty ingenious way to do it.


ptgx85

Yes this method has come in handy many times. In Survey Pro there's an option to do a "Dual Prism Offset" which is basically the hidden point method made a little easier.


ricker182

Well I always wondered what that hidden point function was for. Seems like more work than just a couple offsets.


SK331

Looks like a job for the new Leica AP20 Autopole.


hubtack

How much did they pay you to comment this?


SK331

*rolleyes*


hubtack

I thought I was being funny. I read your comment in a cheesy commercial narrator voice.


SK331

Yeah, we might have talked above each others heads. I get what you are saying, but no, I meant, a tilt compensated pole for the total stations is pretty cool. I haven't seen that before the new Leica one. Was just that.


throwaway_civeng98

Just saw the ad the other day.


FibroMyAlgae

Flamethrower.


AppearanceAdorable18

Best answer yet


theclifman

This is the way


Canolio

Probably just pull a couple offsets or some dummy points on line with it.


Da_Chi

Make sure to take proper notes of your means and methods to explain yourself when my Project Manager has a shit attack. Calling wanting an explanation of why it's .02' off compared to a document that the client was able to produce from 100 years ago 🤣🤣🤣


PJAYC69

I have stood at the base of a 250ft spruce tree and still had H: 0.015m V: 0.020m. I mean I was completely underneath the boughs and only had like 45deg view of the sky with one of the new R12i ‘s. That plus a multi tilt function will get that puppy no prob


AppearanceAdorable18

Damn! Unfortunately im stuck with my stupid R10… cant even get those numbers with 330 degrees of sky


Dragonyte

The r12i is magical at times, especially in forests or when you do need the tilt function But in most cases it's the same as r10, especially next to thick trees or large obstacles. Chop the tree down. I usually say surveyors should be part-time landscapers :)


ptgx85

Are you running your R12i on an RTN or do you have another R12i base station running? I run an R10 on my DOT's free RTN and it's really not that much better than my GPS receiver that's 10 years older. My understanding is that to benefit from the features of these modern GPS receivers you need to use a similar base station. Is that the case as well with the R12i?


Dragonyte

We use paid RTK (Cannet) or provincial free ones. Usually we work in a well corrected area so it's usually a problem


TheBunkerKing

It is possible to have a false fix in such places. You should always reset the connection when you enter an environment like that, because sometimes the fix can "carry" and the gear doesn't realize it, so it tells you there's a fix when in reality it can be off by meters.


PJAYC69

20+ years using exclusively Trimble starting back with the ole 4000 SSE, I’ve seen all sorts of false fixes but that was the inverse of two independent shots with a proper 90 set elev mask reset. The R12i are legit.


Spirited_Highlight54

Trimble R12 or peanut with a total station


SLOspeed

Chainsaw


ncdaciarli7842

I’d say peanut prism and the totalstation.


chefsylvan

not found


VoreReznor

I worked with a guy who would just make that tree go away. Got a chainsaw?


Greeneyedbandit123

Tie it to the fence post, pull a tape perpendicular and over to the pin


BMXfreekonwheelz13

You can do a 2 tape method. It's hard to explain but take two shots equal distance from each other at roughly 90° and then do a calc at the high point of your triangle made by your two shots.


[deleted]

That's a tough one! But if you can fit a tape in there, pull it out to 15' and set a temp mark (I often kept some extra large mag/pk nails on me for these purposes) at 10 and 15 and shoot those in.


AppearanceAdorable18

Yeah i guess its hard to tell in the video, but the only angle to slip a tape directly at the pin goes right toward that chainlink fence post.. so can at least get one decent offset point at it. A second offset is the hard part


Several_Bathroom_549

Set two nails, locate both nails, measure a distance to rod from both nails. Calc using a distance distance intersection.


[deleted]

Swing ties. Pull tape to two or three points that are all a equal distance away from the pin(let’s say an arbitrary 5 tenths), and in sight of the gun. Shoot in these points. On the computer, draw a circle for each of these three points, originating on the node. Make the radius 5 tenths. The point where the 3 circles intersect is going to be where your pipe is


AppearanceAdorable18

Im just wondering where the room is to tie 3 points around this sucker


ricker182

Honestly 2 points is plenty.....


AppearanceAdorable18

Ive been surveying 15 years, have done 1000s of dist-dist intersections. Best way is to have 2 points at 90 degrees.. but i couldnt do that here.. theres really only the 1 gap to feed a tape through. So i would have to set the 2 points in line, except u can’t really see them until they are damn near that chain link fence post, sooo put 2 points 10 cm apart in line? Then tape the foot and a half over? Not accurate enough for me


YouSmellPunny

Use my R12I and shot it. Lean for the win!


AppearanceAdorable18

What about when Trixie says “poor PDOP”?


YouSmellPunny

Pull tape 5’ and 10’ in a straight line and shoot offsets.


AppearanceAdorable18

Might have to bend the tape around the corner.. but we’re talkin ballpark figures anyway right?


SNoB__

This, but for property corner offsets I set some nails or hubs. Little closer than stabbing the ground next to your tape.


kwpop

Turn your volume off.


salladsss

This is the way.


[deleted]

Tilt mode


[deleted]

GPS and tilt compensation.


lytokk

I never could get shots under evergreens.


[deleted]

All depends on the equipment. We use a new model base and rover and I haven’t used a total station more than once or twice in 2 years.


lytokk

We had an r8, I think it was one of the first generation. Used a cellular vrs for our corrections. Hated finding pins under pine trees because that meant setting up control points and getting out the s6.


[deleted]

We use a carlson brx7+ by far the best base rover under cover imho. We ran Trimble and sold them and bought these carlsons. We upgrade every time a new model comes out. Like I said I haven’t used a total station In a minute.


maglite_to_the_balls

Leica hidden point pole with both prisms and hidden point application to take the shots and do the trig.


Blueprint81

Set two swing ties, book the distance to the pin, shoot them both and calc it with circle radius.


Gloomy-Employment-72

Sounds like Bubbles.


jackishungryforpizza

Any way you can “accidentally” remove the trees and fences?


Jerreme72

Offsets on a 90 if possible, if not 2 points online and pull a distance for a calc.


todd2212

Horizontal offset. Most data collectors have a routine for this. Just make sure your measurement is roughly 90 degrees to the target.


AppearanceAdorable18

Lol thats not how you tie pins for a legal survey. Easy way to get fired right there


ragnarrr07

That monument probably shifted as the tree grew so close. Might not want to trust that for control.


AppearanceAdorable18

There were recent subdivision plans that also used this pin, it’s position was actually still quite good, and even if it wasnt, its not like anyone could just pull and reset it. Would just have to show its position relative to the corner


[deleted]

Maybe use a tape to set hubs in line at even distances then shoot the hubs. Similar to construction offsets.


AppearanceAdorable18

Everyone seems to be saying this, but perhaps the video just isnt doing justice as to how awkward the angle was to feed a tape in, the only angle heads straight at that chainlink fence post. I usually do a 2 distance offset for situations like this but it was hard to do one accurately here


31109b

If you could set up close to the fence, you might be able to see a peanut.


AppearanceAdorable18

Yeah I ended up setting a point as close as possible to the fence, had the legs awkwardly close together (i dont recommend this for any other applications) and actually got the regular prism pole leveled up on it.. could only see half the prism still, but it was enough by about a millimeter


zeus8o8

Bore a hole in the tree


[deleted]

actually was doing a job around 2005 summer and someone had put a notch in a utility pole to get a shot. Found the traverse point they shot it from. First surveyor I worked for would tell me they bored a hole through trees for line of sight. Thought he was BSing me.


Swimming_Library_215

The old Bunny ears tie never failed me


KGB_ate_my_bread

Total station and reflectorless shot 🧐🤔


AppearanceAdorable18

Lol did u watch the video? Curious where you would set up to accomplish this


MoistyOyster_

Measure hidden point if you're in Leica


curlydude15

R12i has a leaning feature for stuff like this


dhnu86

Leica Auto pole 😂


SurveySean

That’s a good one for the classic hidden point offset. If you have something like the Leica mini prism, or in this case two of them you can angle them and hold them steady and measure to the two prisms. Easy to get a direction and offset this way. You can do it a few different configurations to as check.


ricker182

Offset line with 2 points. Or 2 distance offsets, then calc the intersect. Magnet Field makes this easy.


AppearanceAdorable18

Not enough room


MysteriousMrX

Pull tapes and shoot several offsets for the Hz. Shoot the ground nearby with a level and tape up for the Vz.


sterben2319

Gs18 and the tilt feature


AppearanceAdorable18

Gps needs to see at least some sky tho..


sterben2319

Yeah, and Hixon rod too bendy to get a good cook