So I have been putting together a total station setup with a Nikon DTM-300 and I'm looking for prisms. Silly question...Does a geodimeter prism work with a Nikon DTM-300?
More specifically, this item labeled as a geodimeter prism...
Pretty sure it would, but I'd want to test out the specs to make sure I have the constants correct.?ÿ Do you have a nearby baseline to test it on??ÿ?ÿ
You need to know the prism offset and set that value in the Nikon.?ÿ Otherwise all measurements will be slightly off. There are ways to determine the prism offset int the field using a series of measurements.
Quoting from Second Edition, Chapter 8.8 EDM ACCURACIES, Surveying Principles and Applications by Kavanagh & Bird:
The EDM prisim constant value can be field checked in the following manner: A line is laid out with end stations and an intermediate station (see Figure 8.9) The overall distance AC is measured along with partial lengths AB and BC.?ÿ The constant value will be present in all measurements; therefore.
AC - AB - BC = instrument/prism constant
Alternately, the constant can be determined by measuring a known base line, if one can be conveniently accessed.
I would also suggest that all line segments be measured from both ends.?ÿ Additional warning:?ÿ Using multiple prisms with different constants on the same job is asking for errors!!!