I understood your question to be what happens to an adjustment when one replaces the actual observations with adjusted values. Using the simplest exam...

On the issue of using squaring L2 receivers for GPS on Bench Mark campaigns, it appears from the official guidelines, NOAA TM NOSNGS-58 (page 5) that ...

Rather than anecdotes, try some of the literature on the subject. I like "Accuracy of GPS-derived relative positions as a function of interstation dis...

Howdy,I used the 4000SST in the early 90's. It was a good instrument for its time. Unfortunately, in addition to its age it has the tragic flaw of log...

FWIW one of the motivating factors for the development of OPUS was experience with users submitting processed GPS data to NGS. It was often the case t...

My reading of the contours shows the differences in ellipsoid heights to range from 0 meters in SE, +0.5m in the middle, and +1.0 m in the Aleutians.T...

The links below are (respectively) an image of the changes to ellipsoid heights, a presentation on the state of the vertical network in Alaska, a file...

The new height is ten feet LOWER...

Unfortunately the nice treatise includes wrong parameters for GRS80. See Dr Milbert's post on GRS80 parameters to this site. Thread was GRS 80 not mer...

To see the situation in Texas, take a look at the chart linked here: It shows the age distribution of licensed surveyors. Whether some in the highest ...

Don't know whether ot meets your requirements but check out: They have a Geomatics option. Lots of links on the page including scholarships and intern...

Excuse the tardy reply to Bill's question. I am currently in Hawaii with only my iPad. I take the opportunity to expound beyond his question (prompted...

For a more sober explanation see:Last visited the Observatory in 2005. Some photos, including my Garmin on the line, here: The basis for the spate of...

Not to re-irritate the issue, I still feel that the monument shows signs of damage which could have impacted its height. There have been eighty years ...

Your picture of the monument shows it has been damaged with the left side showing significant damage and a crack on the top and bottom of the disk. Th...

Retrieving projects associated by PID is done here: There was a tool on the NGS site that became an orphan, LineTool, that was invaluable to me when a...

FWIW,iUsing the relationship h - H - N = 0 and your h and the published H we get a geoid-ellipsoid separation of 16.305 m. The modeled value is 16.39...

I hesitate to respond as I am not clear what you are trying to say. Your diagrams do not help. Probably my problem.Nonetheless, the statement you make...

On the issues related to GPS site monumentation, check out the nice summary with links at: Lots of interesting technical details. While the UNAVCO sit...