Hello guys
Kindly I need your advice on what's the different between the Resection and Backside procedure in term of accuracy and which procedure is more popular and, which procedure cause of that the rotation of the site.
Thanks
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Replies
I imagine you are refering to a backsight procedure. That for years has been the most common. You set up on point with a known coordinate and then record your angle and distance to another point with a known coordinate. A resection involves you setting up on a point with unknown coordinates and shooting multiple points with known coordinates. This will then calculate where you are loctated.
The backsight procedure only has one set of data to check, so if you setup on point 1 and backsight point 2, but you tell the software the opposite you will be 180 degrees out. You only have one set of angle and distances to check the accuracy of these 2 points. Most people when using this method will also turn and check into another point and verify their accuracy of their setup before starting to work.
The resection method will take all the angle and distances to calculate your position along with showing you the residuals from the different points used. I typically use 3 or more monuments at different angles for this method.
I like the resection method, but it requires more monuments to get started to guarantee the acccuracy of the setup. Even though the resection method is my favorite, I hardly use it for this reason. Don't forget you can only be as accurate as the monuments you are using for your setup.