sanpoilsurveying 2018-12-01 10:52:35

Very good presentation.

SLeotta 2018-11-30 09:52:19

Well presented materia.

tlgibson 2018-11-16 10:47:47

I have had some training on this subject but was still confused. This course cleared up my confusion and made sense of the different models and datums and how to go about determining what datum to select for my projects.

fischerc57 2018-10-31 12:08:35

This course provides further clarification to my geodetic studies

vmendoza 2018-09-28 13:28:32

It will definitely give you a better understanding of Vertical Datumes

JTedesco 2018-09-25 10:16:59

Good introduction to the subject.

boggs.david@gmail.com 2018-09-19 01:40:52

no

elizestuaries 2018-08-08 22:20:22

Good at giving basic background information! Quite helpful!

cassy.porter 2018-08-07 11:22:06

The lesson was informative but the layout was a bit confusing at times. Seemed to jump around a bit..

jcub 2018-07-18 08:24:11

great course needs more audio and video

megan.shapiro 2018-07-10 15:07:16

It would be very helpful to see more detailed results in our quiz scores- see what we answered and what the correct answer is with an explanation for the correct answer.

Miguel Toralla 2018-05-26 21:23:06

none

Kit Alexander 2018-05-17 15:22:19

Very good lesson with a helpful quiz

brandygeiger 2018-04-06 17:48:48

Relvant for understanding datums and how they are used in Hydrographic Survey

adieppa 2018-03-15 20:35:05

Great lesson, although I had some knowledge my understanding increased significantly as evidenced by the final quiz.

rickolejniczak 2018-02-26 15:32:13

This is a great class for an introduction to the subject matter. Review quizzes help to reinforce learning. Highly recommended.

ar2661dl 2018-02-21 22:27:22

very helpfull

corrigan 2018-02-13 12:30:07

i wish the test would help you understand why you got it wrong vs just telling you its wrong.

in4111dv 2018-02-12 13:30:17

No comment

carbon98 2018-02-08 14:37:40

kjgjhgl

wslater1 2018-02-08 10:55:01

Unless you have an amazing vocabulary, this it pretty complicated

ggano 2018-02-08 10:07:23

Great

Gliff 2018-01-16 12:47:13

Thanks

alwardi 2018-01-13 21:04:45

great

GPSman 2017-12-19 22:27:49

As an entity identified with surveying, a poll such as this one should not be called a "survey".

w.wefel 2017-12-09 22:51:15

Good comprehensive overview of height systems. The mystery of the St. Lawrence River flowing uphill is explained!

durces 2017-11-22 10:11:42

Thank you

SanAntone 2017-10-04 12:21:18

This lesson on understanding heights and vertical datums is helpful for a broad overview of the subject, however, it might require more than once going through it to fully absorb all the material. I wish there were more examples of what the various datum systems describe since it's not so easy to see what the differences are. Also, the 18th century controversy between Newton and Cassini does not explain what methods they used to settle the question, but perhaps that is beyond the scope of this lesson.

oladotunonas 2017-10-03 10:07:44

The study is good and has the capacity to increase the knowledge of students. The lesson materials are also fixable Nad easy to understand.

vipin kumar maurya 2017-10-03 04:07:54

Very good material for concept clearance and pracice

kevin_morris@nps.gov 2017-09-27 12:55:02

Enjoyed the lesson.

dobnc60@gmail.com 2017-09-26 09:00:46

I am a licensed Land Surveyor and this type of online training is very helpful to maintaining my understanding of issues related to my profession.

JonathanPrice 2017-09-21 06:28:02

Lesson may be easier to follow if more animated video explanations are done.

dmelton 2017-09-11 19:49:44

A very good introduction to the subject of datum and the difference between an ellipsoid and a geoid.

elsy-ngalaha 2017-09-10 21:10:56

Wonderful

bushasarrived 2017-08-22 18:34:19

Gives a good general understanding of vertical datums and the principals behind them

rrustan 2017-06-30 13:37:25

MCDitches 2017-06-23 14:17:50

This course gave me a much better understanding of heights and vertical datums.

rmorrison 2017-06-23 12:56:16

Good.

alexosfera 2017-06-02 05:30:57

I'm sure you could not imagine it!

matthewjohnson 2017-04-26 14:36:35

jfabian 2017-04-12 07:13:58

Great overview of the intricacies involved with determining "height".

jendowe 2017-02-27 14:23:53

Very informative!

504633 2017-02-26 21:25:38

A very good introduction for understanding heights and vertical datums.

joeh 2017-02-06 07:22:30

I would like to see more examples in understanding the heights and vertical datums.

jajuarez 2016-10-31 18:21:21

Nice course, for learn about heights and vertical datums

485606 2016-09-25 08:07:18

I would strongly recommend this course for all GIS oriented students. It is very good opportunity to learn new skills.

pic2 2016-09-20 16:53:10

I really appreciate the training regiments, and the opportunities to be able to utilize them, they are really great tools, and well defined educational proprieties.

ecliptico 2015-04-17 10:45:23

I liked a lot!!! thanks NGS

rolando.flores 2015-04-15 11:29:02

Great learning module, Thanks NGS and others who help put this together.

jay.satalich@sbcglobal.net 2015-04-08 21:30:57

Great overview, kudos to NGS for helping to create this.

1. Describe how heights and vertical datums are used in surveying.
   • Define height as used in the context of surveying and mapping.
   • Define vertical datum.
   • Provide reasons for choosing different vertical datums.
2. Identify types of vertical datums and their associated heights
   • Define an ellipsoidal datum.
     • Define an ellipsoid.
     • Describe the global nature of ellipsoidal datums.
     • Define an ellipsoidal height.
     • Describe strengths and weakness of ellipsoidal datums.
   • Define a geopotential datum.
     • Describe earth’s gravity field.
     • Explain why geopotential datums help describe water flow.
     • Define the geoid.
     • Recognize NAVD 88 as the current geopotential datum in the U.S.
     • Define orthometric height, geoid height/geoid undulation, and dynamic height.
     • Describe strengths and weakness of geopotential datums.
   • Define a tidal datum.
     • Describe the local nature of tidal datums.
     • Explain why tidal datums are important and what they are used for.
     • Describe strengths and weakness of tidal datums.

national geodetic survey, benchmark, bench mark, survey mark, vertical datum, datum, standard datum, ellipsoidal datum, geopotential datum, tidal datum, ellipsoidal heights, gravity field, geoid, the geoid, geopotential, geopotential datum, orthometric, orthometric height, geoid undulation, dynamic height, elevation measurement, reference surface, NAVD88, NAVD 88, U.S. national spatial reference system, NSRS, GPS, GNSS, official U.S. datums, ellipsoid, ellipsoid height, U.S. Global Positioning System, Global Navigation Satellite Systems, World Geodetic System 1984, WGS 84, WGS84, earth gravitational model, gravity anomalies, equipotential, equipotential surface, gravity potential energy, geodetic leveling, local mean sea level, International Great Lakes Datum, IGLD, dynamic height datum, mean sea level, zero height surface, ocean dynamic topography, Mean Sea Level, local Mean Sea Level, MSL, Mean Low Water, MLW, Mean High Water, MHW, Metonic Cycle, National Tidal Datum Epoch, National Water Level Observation Network, NWLON, tide station, Center for Operational Oceanographic Products and Services, CO-OPS