I received a set of plans today with the a table of N. Coordinates and E. Coordinates that refer to several bench marks (for lack of another word) for this project.
I cannot convert these or make any sense out of them, can anyone enlighten me please?
N Coordinate 260990.992 E Coordinate 1783049.025
It should be in the vicinity of 40.889096° -78.420768°
Thanks for looking. Jeff
I Believe You Have PA SPC N And Need PA SPC S
That Latitude puts you on the N/S SPC border.
Paul in PA
> N Coordinate 260990.992 E Coordinate 1783049.025
>
> It should be in the vicinity of 40.889096° -78.420768°
Latitude 40.889096°
Longitude -78.420768°
Calculated Values - based on Degrees Lat Long to seven decimal places.
Position Type Lat Lon
Degrees Lat Long 40.8890960°, -078.4207680°
Degrees Minutes 40°53.34576', -078°25.24608'
Degrees Minutes Seconds 40°53'20.7456", -078°25'14.7648"
State Plane X Y (Meters) 3701 543470.938mE 80447.568mN
X Y (US Survey Feet) 3701 1783037.568ftUSE 263935.062ftUSN
X Y (International Feet) 3701 1783041.134ftE 263935.590ftN
Position 3701 543474.42976886 79550.2134620269
Zone 3701 - Pennsylvania North
Meters US Survey Feet International Feet
X 543474.430 1783049.025 1783052.591
Y 79550.213 260990.992 260991.514
Calculated Values - based on Degrees Lat Long to seven decimal places.
Position Type State Plane - Pennsylvania North
Degrees Lat Long 40.8810160°, -078.4206441°
Degrees Minutes 40°52.86096', -078°25.23865'
Degrees Minutes Seconds 40°52'51.6575", -078°25'14.3188"
State Plane X Y (Meters) 3701 543474.430mE 79550.212mN
X Y (US Survey Feet) 3701 1783049.025ftUSE 260990.988ftUSN
X Y (International Feet) 3701 1783052.591ftE 260991.510ftN
UTM 17T 717328mE 4528751mN
South yellow dot is N Coordinate 260990.992 E Coordinate 1783049.025
It is definately SPC N
Paul it is in SPC N but something still isn't quite right.
According to what I have, the South point you have on GE should be at the intersection where the North point is. All point I have are on the roads or trails, not out in the sticks. :-S FWIW I got the same results as you did, but I thought maybe I wasn't seeing something.
Has someone tried to project it to ground by applying the CSF to the coordinates?
> Has someone tried to project it to ground by applying the CSF to the coordinates?
That would also shift them east/west.
I don't have the benefit of knowing how these coordinates were determined or the accuracy of the provided lat/lon, but the goof is almost entirely N-S and approx 3000'. It would only take changing the thousands digit in the northing from a 0 to a 3 to put you real close to the intersection where the lat/lon fall.
Perhaps the one in the woods is correct, but it does show it on the plans at the intersection. He is giving me AZ Line N 0 01 35 W Baseline N 1 05 56 E that should intersect an IP @ 265641.519N 1783080.682E.
Thanks for looking, my eyeballs are on my cheeks now, I'll have to look at more tomorrow.
It Was A Transposition In The Decimal Degrees
When they entered the Lat in decimal degrees, instead of 40.889096° they entered 40.880996°.
I learned about transpositions from my wife who worked as a bank teller when we were first married. If the error is a multiple of 9 look for a transposition and the size of the error tells you which numeric column to look in.
A 3,000 error did not fit, but when converted to meters it is about 900m. That error did not fit the data, BUT!
Considering the earth is 40,030,174m in circumference divide by 360° = 111,195m per degree. 900/111,195 = 0.00809, close enough to 0.0081 to lead me to the decimal degree transposition at the third and fourth decimal place.
40.889096
-40.880996
= 0.008100
Class dismissed.
Paul in PA
E greater than N
"N Coordinate 260990.992 E Coordinate 1783049.025"
Your eastings are greater than your northings, is this a US thing?
PA Is Wider Than High, Plus It Has N/S Zones
Transvere Mercator system set up for best available accuracy.
We're happy with it.
Paul in PA
It Was A Typo
The data was given in northing,easting not in decimal degrees.
After inspecting the drawing and associated points, I believe that it's just a simple typo. It should have read N263990.992 E1783049.025 and not N260990.992 E1783049.025.
Dumb on my part not to inspect the drawing carefully, I had just put into GE and knew that something was amiss, I felt that I was having a conversion issue, as Paul has said this is near the N/S point for our SPC in Pennsylvania so there was opportunity for error on lots of levels.
I have notified the powers that be about the possible typo.
Thanks everyone for your input.
It Was A Typo
There was a thread a few months ago that warned of the dangers of scanning errors. It provided examples of where the original was a bit fuzzy and the computer-generated best guess changed a digit to a different digit. Human error, of course, would be the most likely culprit.
I have problems with all of the round digits sometimes being mistaken for a different round digit when things are fuzzy. 68903 or 38803 or 68888
Yup! --- Confusion resolved
Response from my friends at DEP:
Jeff: You are correct. As confirmed from the project mapping control report; the North Coordinate for BM DEP-1 is 263990.992. Thanks, Mark
Now Paul, we may dismiss the class 😉
Yup! --- Confusion resolved
I thought I was following the data stream.
Paul in PA
PA Is Wider Than High, Plus It Has N/S Zones, Whoops
Lambert Conformal not Transverse Mercator.
Paul in PA