Hi all
whats are the Formulae for
1. reduction to ellipsoid correction
2. Line scale error coreection
using final stations heights to compute
Any help would be great
Cheers
Mat
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According to Phil Stevenson of NGS, there is no direct connection between GPS coordinates & a tangent plane survey. Fortunately, there are some pretty good solutions to the problem. I am generally faced with the task of incorporating GPS control into a traditional theodolite survey. I usually work in heavily wooded areas with few good GPS sites. It is rare that I can survey anything with GPS alone. GPS coordinates are easy to deal with as they can be converted to Lat. or Long., grid or surface with simple conversion factors/ formulas. Incorporating tangent plane data can get a bit sticky. I believe most DOTs make adjustments at regular intervals over long distances.
hello.
you can find it at the end of your total station field user book.
at list at the leica´s field user book.
Hi friend look this link...
https://drive.google.com/open?id=0BypSvc79Wjc5bWd0aFp3MFFuN00
From PS reference handbook:
Orthometric correction:
Correction = −0.005288 sin2φ h Δφ arc1′
where: φ = Latitude at starting point h = Datum elevation in meters or feet at starting point Δφ = Change in latitude in minutes between the two points (+ in the direction of increasing latitude or towards the pole)
h ≈ H + N
where: h = Ellipsoid height N = Geiod undulation H = Orthometric height
Here Mat,
Some of this might help.
https://rplstoday.com/community/threads/geodetic-reduction-question...
http://www.ngs.noaa.gov/web/science_edu/presentations_archive/files...
https://en.wikipedia.org/wiki/Earth_radius#Gaussian
https://en.wikipedia.org/wiki/Earth_radius#Directional
https://en.wikipedia.org/wiki/Earth_radius#Principal_sections
Hi Mat,
Is this what, you are looking for. I am confused on your ? But look over it
I have a lot of Data on this subject.
This site has a lot of good info plus this. Go Thru Geodesy also.
Look under Corrections
http://aplitop.com/subidas/ayuda/en/MDT-Topografia/index.html#!reductionToEllipsoid
http://aplitop.com/subidas/ayuda/en/MDT-Topografia/index.html#!scaleFactorDueToHeight
Read this also
http://aplitop.com/subidas/ayuda/en/MDT-Topografia/index.html#!anamorphosis
Here is some good reading.
http://www.esri.com/news/arcuser/0703/geoid1of3.html
Here from NOAA , I sent these 2 to Raymond Kinglsy on one of his Discussion.
But NOAA has a lot more on this subject at there site.
http://www.ngs.noaa.gov/GEOID/PRESENTATIONS/2007_02_24_CCPS/Roman_A...
Hi Mat,
Did I forget to tell you I added one on Geoid and MSL, there is also some more info on it.In the others. Thanks for the programs again i never seen these P to R or the R to P. I like it,very short, i like that. that is why i use mine so much. I will try them in some programs.