can you have a job where you use both GPS (calibrated to match office assumed coords) and the total station to stake improvements? ive noticed that when i do this, under job properties (trimble) the projection goes to local site.?ÿ ive been taught that you must stake everything with a scale factor 1 for total station work.?ÿ in the past, ive had PLS say to have a seperate job for all GPS.
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can anyone explain scale factor, local site, and integrated survey?
ive been taught that you must stake everything with a scale factor 1 for total station work.
You have been taught wrong. Or, perhaps, you misunderstood.?ÿ You can, absolutely, set up a total station job in a projection system and work away. The dc will apply the appropriate scaling to the measurements (although your raw data file will contain the unscaled distances). If you get an argument I'd ask why the dc allows you to do that if it can't be done.
Now, there may be very good non-technical workflow reasons that your PLS doesn't want you to do that. So tread lightly here. Nevertheless it could be a case of not?ÿ knowing how things work. If so your PLS is in, if not good, at least then numerous, company.?ÿ?ÿ
About 4 years back I was in a project kickoff meeting with 3 other PLSs, including our survey manager, and a couple of experienced techs. Of all of them I was the least involved in the project. Only in on it because the whole damned department was. We had control and a topo?ÿ in state plane.?ÿ We had a design built on that topo, so it was state plane.?ÿ We were going to be staking with total stations because .... because ..... I don't know. It was just going to be done that way.?ÿ The question before the meeting was how were we?ÿ going to deal with the scale factors involved? Scale the control and design CAD??ÿ Enter some scale factor into the dc every day? The group was floored when I finally tweaked to what they were cooking up and told them to just set up the data collector job in the appropriate state plane zone?ÿ and get to work.?ÿ ?ÿ
Back in the day (1989) we used gps control with conventional surveys all the time.
With today??s software trying to help you out, there??s a lot to keep track of. But distance is distance. Ground, LDP grid, SPC, UTM, geodetic. It??s all in being vigilant.?ÿ
can you have a job where you use both GPS (calibrated to match office assumed coords) and the total station to stake improvements? ive noticed that when i do this, under job properties (trimble) the projection goes to local site.?ÿ ive been taught that you must stake everything with a scale factor 1 for total station work.?ÿ in the past, ive had PLS say to have a seperate job for all GPS.
?ÿ
can anyone explain scale factor, local site, and integrated survey?
In trimble access you can certainly use a total station and gps at the same time. just make sure you know what co-ordinate system you are using and set it in the job properties. the total station measurements will have a scale factor applied to them automatically if there is one.
If you do a GPS calibration then it is in fact a "local site". The scale factor will be whatever was determined in the calibration. (it can be fixed to 1 in the calibration if this is desired)?ÿ
We began a discussion Friday on mixing GPS, we use only RTK, and total station. A point was made that just because your backsight check distance is off by only 0.02' or 0.03', you must consider your angular error too. I raised my hand and asked what we should use as a reference bearing to check for angular error. More about the subject will be discussed next Friday.
