mulucaver
Member
I don't want to get into accuracy or precision as that's already been covered in other posts but I'm interested in other surveyors' views on the grading which should be recorded on the finished map.
The BCRA grading system is related only to the method of surveying and not to the final accuracy so, if I measure to within 1 degree and 1 centimetre I would record a grade 5.
However, when I do the data reduction and I find a loop closure error of say 10%, this certainly means there is either a blunder or a systematic error, which by definition means the survey did not achieve expected accuracy.
Should I therefore downgrade the survey or can I assume that by applying loop error correction the data is now to the expected accuracy?
If the whole survey is a loop then this seems to be acceptable but what if the loop was only a small proportion of the whole survey? If there's an error in the loop one could assume a similar error may be present in the rest of the survey, unless it's a blunder, and this won't be corrected by the software.
With that size of error, of course, you should resurvey that section but that's not always possible on far flung expeditions. Downgrading the survey grade would at least indicate that there may be a problem.
The BCRA grading system is related only to the method of surveying and not to the final accuracy so, if I measure to within 1 degree and 1 centimetre I would record a grade 5.
However, when I do the data reduction and I find a loop closure error of say 10%, this certainly means there is either a blunder or a systematic error, which by definition means the survey did not achieve expected accuracy.
Should I therefore downgrade the survey or can I assume that by applying loop error correction the data is now to the expected accuracy?
If the whole survey is a loop then this seems to be acceptable but what if the loop was only a small proportion of the whole survey? If there's an error in the loop one could assume a similar error may be present in the rest of the survey, unless it's a blunder, and this won't be corrected by the software.
With that size of error, of course, you should resurvey that section but that's not always possible on far flung expeditions. Downgrading the survey grade would at least indicate that there may be a problem.