International Standard for Electronic Tacheometers (ISO 17123-5) is what a surveyor needs to look at to test
their Total Station. In the standards it says; " Before commencing surveying, it is important that the operator investigates that the precision in use
of the measuring equipment is appropriate to the intended measuring task".
"The electronic tacheometer and its ancillary equipment shall be in known and acceptable states of permanent adjustment according
to the methods specified in the manufacturer's handbook and used with tripod and reflectors as recommended by the manufacturer."
I don't know what Paul in PA read but the above statement clears up his statement.
Yes it cost money to get these standards. If say 10 surveyors chipped in to get the above standard then the price would
be $16.20 per surveyor. NOT BAD.
You can get the ISO standards from: ANSI (American National Standards Institute, phone # 212-642-4980
e-mail info@ansi.org
JOHN NOLTON
JOHN NOLTON, post: 440515, member: 225 wrote: International Standard for Electronic Tacheometers (ISO 17123-5) is what a surveyor needs to look at to test
their Total Station. In the standards it says; " Before commencing surveying, it is important that the operator investigates that the precision in use
of the measuring equipment is appropriate to the intended measuring task"."The electronic tacheometer and its ancillary equipment shall be in known and acceptable states of permanent adjustment according
to the methods specified in the manufacturer's handbook and used with tripod and reflectors as recommended by the manufacturer."I don't know what Paul in PA read but the above statement clears up his statement.
Yes it cost money to get these standards. If say 10 surveyors chipped in to get the above standard then the price would
be $16.20 per surveyor. NOT BAD.You can get the ISO standards from: ANSI (American National Standards Institute, phone # 212-642-4980
e-mail info@ansi.orgJOHN NOLTON
I wonder why 'precision' is used as opposed to 'accuracy'. a 5" leica 1205+ is as precise as anybody would want (< 0.5"), but uncorrected, the readings aren't always very accurate.
I think I know the arrangement of the angular test, but not the EDM part. I think you can do better than the ISO test though by testing against known angles.
I'll pledge AU$20 if u take PayPal.
Conrad, post: 440652, member: 6642 wrote: I wonder why 'precision' is used as opposed to 'accuracy'. a 5" leica 1205+ is as precise as anybody would want (< 0.5"), but uncorrected, the readings aren't always very accurate.
I think I know the arrangement of the angular test, but not the EDM part. I think you can do better than the ISO test though by testing against known angles.
I'll pledge AU$20 if u take PayPal.
"Accuracy" is more the product of the method, the operator and the software. "Precision" is more the product of the manufacturer, the equipment and the firmware within.
I was aware of a newer standard but had no recall of the Name. It is my understanding that as a part of the purchase contract you agree not to share it. The precision one wants with an instrument depends on the job specifications of the at hand. For many jobs a too precise instrument can be a detriment to the workflow pace.
Least squares can improve the precision, but not always the accuracy.
Paul in PA
Paul in PA, post: 440657, member: 236 wrote: It is my understanding that as a part of the purchase contract you agree not to share it
Good point, noted.
The precision one wants with an instrument depends on the job specifications of the at hand.
Really? The different total stations I have at hand have, as near as makes no difference, the same precision as each other. I select them based on their accuracy depending on the job specifications. I only usually see accuracy specifications quoted for instruments, not precision.
Least squares can improve the precision, but not always the accuracy.
I'm going to dispute this assertion. For years I was making observations that were as precise as anybody would want for any reason, but weren't as accurate as they could be. Least squares adjustments were improving the accuracy of the parameters being solved for, and thus the accuracy of the adjusted observations. Precision of the adjusted observations isn't a thing as far as I'm aware
Perhaps we are using different terminology to describe the same thing?
