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PrismPROCEDURE

- Before measuring, the detail that will be measured(mapped) should be sketched and then each datashould be written on the sketch.

- Determine the base line (measure line) on the field, ifpossible pass the fix points or not, then the direction ofthe base line can be determined with compass.

- Put svalon on point A and B- Measurer with the prism stand in front of the detail

point a approximately at measure line AB

- With the help of measuring helper at point A, so theposition of the prism set until AaB become straight linein the other hand, the svalon shadow A and detail a

placed coincide.- Measure the length of Aa and aa with measuring tape

and write the result on the data paper.

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Prism

CONCLUSION

- Prism function in measuring with simple toolsisprojecting the points that will measured on themeasuring line

- Because the reach of prism is short, so prism canonly used for small area mapping

- Accuracy in reading the prism is needed in thispracticum, which is in shooting, prism and shootingobject / point must be perpendicular.

- Before measuring it would be better to know thecondition of the field very well, because it will beaffected on determining the base line that will beused as reference from measuring.

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POLYGON MEASUREMENTInner Angle of Polygon

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CONCLUSION

The angles obtained from the calculation of the result of field measurement is 9001105 with 8station points with the total of angle based on the theoretical calculation are 90000'00". Thus, thetolerance of differences of the total angels in calculation and total angles in theoretical is:

Based on the above tolerance limits obtained the difference of angle in the angle theoreticalcalculation of 0000'10" so, the angle in polygon in the result of the field measurements is in thelimit of tolerance.

Coordinates of the station point and polygon detail points in a row are as follows:

Station Point: A ( 0;0) E (-33,533; -0,2524)

B (32,4571;-1,9915)

C (33,3552; 40,4992)

D (-25,8164;45,5699)

Detail Point:

A1 (2,8565;-5,2536) D3(-32,8937;65,5567) A2(3,0846;-9,2556) E1(-42,6818;0,6163)

B1(22,3438;12,2168) E2(-14,0159;0,6163)

C1(35,09;42,4089) E3(-12,3072;13,2378)

D1(29,5787;45,7724)

D2(-39,1929;65,5567)

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THE ERROR FACTOR

There is a deflection in the meter indicator,causing the data obtained are not accurate.Inaccuracies in the data due to the deflection at

short distance smaller than the inaccuracy of dataover long distance.

At the time of shooting the point, shooting pointof ordinary and extraordinary angle are not at the

same point. This is causing the differences of theresult between the ordinary and extraordinaryangle that sometimes inappropriately 18000'00".