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Tuesday, September 29, 2020

Advantage and disadvantage of plane table survey

 Advantage

       It is most suitable for preparing for small scale maps.

       It is the most rapid method

       Field book is not necessary as plotting is done in the field concurrently with the fieldwork and hence the mistakes in booking the field notes are avoided.

       The surveyor can compare the plotted work with the actual features of the area surveyed and thus can ascertain if it represents them properly and cannot overlook any essential features.

       There is no possibility of omitting the necessary measurements as the map are plotted in the field.

       Errors of measurements and the plotting may be readily detected by check lines.

        Counters and irregular objects maybe represented accurately since the tract is in view.

       It is particularly advantageous in a magnetic area where compass survey is not reliable.

       It is less costly than a theodolite survey.

       No great skill is required to prepared maps.

Disadvantage

       Plane table is essentially a tropical instrument.

       It is not suitable for work in a wet climate.

       It is heavy and awkward to carry.

       There are several accessories to be carried they are like to be lost.

       It is not intended for accurate work.

       If the survey is not to be re-plotted to a different scale or quantities are not to be computed.

       It is a great inconvenience in absence of the field notes.

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