Activity Feed › Discussion Forums › Software, CAD & Mapping › Change Prism Constant Carlson Survey Edit-Process Raw Data
-
Change Prism Constant Carlson Survey Edit-Process Raw Data
Posted by laxbobcatsurveyor on March 9, 2019 at 1:27 pmI am using SurvCE and Calrson Survey. The prism constant was set to an incorrect prism constant during the survey. Is there an easy way to update this either in SurvCE or Carlson Survey Raw Data editor, so that I dont have to re run the survey?
laxbobcatsurveyor replied 5 years, 7 months ago 4 Members · 8 Replies -
8 Replies
-
In Carlson Survey – Edit Raw File – Edit – Modify Measurements – Modify distance.
You need to figure out whether your distances should have been longer or shorter (by the difference between the right and wrong prism constant).
It worked for me when I used a -17.5 prism and the instrument was set to -30. I think I increased the distance by 13, but it might have been the other way round…
I use Carlson 2010 but I imagine it’s still the same or very similar.
-
So you are subtracting the PC manually from each measured distance? Does SurvCE show the PC for each measurement in raw data, and allow edits?
Magnet shows the PC in raw data, and it is just as easy to edit as a rod height.
-
In edit process raw data there are measured distances. There is also referenced coordinates. If I update the distances manually will I need to update the coordinates manually, or will those auto update. Really I think there is a way to do a global change then re run my compass rule. I just don??t know how and didn??t know if there was an experienced Carlson user that could point me in the right direction.
-
I have done it on the data collector back in the days of Allegro/1200 dominance. It was easy, just edit and re run the raw, the crd would update also, although I do not remember what it did as far a record keeping.
-
Did you just change the prism constant somewhere, or did you have to change all distance measurements?
-
The method I suggested changed all the distances by the amount entered and changed all the coordinates calculated by those distances appropriately. There may be other ways but that worked for me.
-
The correction that I remember making was gross distance blunder on a the first or second leg of a traverse that I did not catch until I was a couple stations along. So not the same type of edit but still established that the resultant set ups and coords are corrected.
-
Perfect that’s what I was looking for. Thank you sir
Log in to reply.