Trimble DC Files – Prism Constants are not Added in Raw File.


The Trimble TSC3 DC file that gets exported from the Jigger DOESN’T add the Prism Constant to the slope distances. This mean they are the RAW observations without the correct adjustment being done to those distance on the Total Station. 

I also downloaded an SDR file of the same job and compared those 2 files and the SDR file DOES have the prism constant added showing in this case a 31mm difference between the 2 points. The DC is the raw file without any calculations being added to it, where the SDR file has calcualtions added to it therefore not the raw file.

I was taught very early on in the peace that you always had to have the Prism Constant set on your jigger so that you get the correct answer. The DC file now relies on the Survey Software to add this data to your slope distances which i think goes against everything i was shown in the beginning.

So just be very carefull when using a DC file and make sure you check to see if the software you are using automatically adds the Prism Contant to the slope distance or NOT.

It will make a huge differnce.