2 If the HI of the instrument below is 693 what is the eleva

2. If the H.I. of the instrument below is +6.93, what is the elevation of the point in question and using stadia, what is the approximate distance from the instrument? 7 26 #5 Elevation 3. If slight movement of the eye from side to side or up and down produces apparent is said to exist. This movement of the cross hairs over the image, phenomenon can be corrected by the cross hairs.

Solution

2) Here as multiplicative & additive constants are not given, so we have to assume standard values.

Multiplicative constants, K = 100

Additive constant, C = 0

Elevation = HI - staff central stadia reading

HI = 6.93

Central Stadia reading = 4.4

Elevation = 6.93 - 4.4 = +2.53

Distance = K x Stadia intercept + C

Stadia intercept = difference between upper & lower stadia reaadings.

Stadia intercept = 4.78 - 4.06 = 0.72 units

Distance = 100 x 0.72 + 0 = 72 units

3) If sight movement of the eye from side to side or up & down produces apparent movement of the cross hairs over the image, Parralax is said to exist. This phenomena can be correted by proper focusing the cross hairs.