Here for our DOT they have a similar method. Scale factor x’ coordinates to get to ground yet they do set up a false northing and easting historically...

@norman-oklahoma I know. I was just being a little honorary is all.

@rfc I believe you can do simple Helmert around the centroid no scaling on either side. This would show the best fit of your points to his points and ...

Uhmmmm this particular survey has made it easy. But to go from grid to astronomical statements are not truly correct. Grid to geodetic is the conver...

Where they all started. The rail road. Don’t know if this will help but remember the difference in regular curve and rail road degree of curvature. A...

  I had a job one of our other offices did. The base set up was in a very questionable area. They logged about 4hrs of data. It was sent off to...

@jimcox it might be for the best as the airports are under staffed and no body is getting a pay check either while our government is shutdown. I was t...

  When I was at the government I was scolded my first few weeks from those with PHD’s that using the verbiage of atomic clocks was not acceptab...

  one word TIME. Each satellite has an atomic frequency standard each satellites atomic frequency standard has its own clock drifts. More satel...

If that changed I didn’t catch it. The real site still states only GPS as of today. But maybe they have not updated the opus main page but who knows. ...

  You are correct OPUS only process GPS data only even if other constellations are in the file. The Beta version as @john-hamilton states wil...

Have fun. I have not been in many years. Maybe I will plan to go next year. I looked at the classes offered this year and a few struck my interest. B...

  I guess so. But stones cedar stakes those surveyors before us and still to this day find them. And they didn’t have the precision equipment w...

@holy-cow just had one of those this weekend. Pacing through the woods along a back line. Ding ding mag locator goes off. I start kick all the fall le...

send it off to the Trimble center point. Online processing service. I hardly see a difference between it and OPUS from same data set.  

I drove the pipe first. Then I had a nice set of vice grips large ones where we had welded some flat steel on them. And had a pair of channel locks sq...

@bill93 you could be right. Just from the look the 5/8” appeared older and fit the pipes found better. Here I have seen nails and rebars all sizes. I ...