Crew goes out to set BMs for construction project. They set the points with GPS and then run differential levels through the points. Crew ties the points as a 3 minute "topo" point, not "observed control".
The elevation is grayed out so I have no option of editing the point elevation in TGO but I'm fairly sure I can make this work.
Any thoughts?
You can add a control class coordinate to the point with elevation only.
Some questions...
Were all of the BMs picked up as RTK rover points?
Was the GPS base station point included in the level run?
Is a geoid model being used in the data collector? In TGO?
Do you want to hold one BM as fixed and adjust the GPS positions to fit it?
You can insert a vertical control point into TGO by selecting INSERT > POINTS (or hit F8) from the TGO pull down menus, giving the point a name/number and keying in the elevation from the level run. This keeps the conventional data separate from the GPS observation. From there you can select SURVEY > ELEVATION ADJUSTMENT and apply a correction constant to the GPS points. This might be the simplest way. There are others.
There is unlikely to be a difference in results between a 3 minute 'topo point' and an 'observed control point'. These simply reference the settings for 'topo point' and 'observed control point' in the particular survey style used on the data collector.
I imagine that the leveled elevation difference from the GPS elevation is a random #. One .04' high, then the next .02' low, ect. The only way I know to edit the RTK elevation is to edit each rod height and then recompute the file. Of course, I'd probably make a copy of the file before I started something like that.
