-32-
Thus,
x = b
p £ f
(81)
0. 4 5/-L.Z
Equation 8l is the "basic equation for determining the Maximum Bridging
Distance for a combination of fXp ,f-L 0 , f , B and Z. For the
sake of convenience, the following two equations are derived from
equation 8l;
m
bd (feet) = 0.4 3 B
jU, f S
¡JUoZ
m bd (meters) = 0.047B
In equations 82 and 83,
/X f S
(82)
(83)
jLLo Z
jUL is the tolerated mean square error in planimetry measured on the
publication scale of the map (in inches or millimeters)^
^f o is the accuracy (mean square error) of measurement of parallax in
the stereomachine in the image plane (in inches or millimeters)^
f is the principal distance of the camera used (in inches or milli
meters )>
S is the map scale number,
Bis the average length of the aerial base (in feet or meters)^
Z is the average flight height above ground (in feet or meters).
The same line of thinking is used to determine > using
equations 50 thru 53> 56 and 57 thru 68. Dropping the terms of
negligible effect (the terms involving in this case), we get:
f1.B (! - £f * * <£>*. z 2 < \ -||> 2 ).
f B
2 +
(84)
/4 H = ^f-X 2 * ~ 2 4 + ~ °* 2 ^3 + 2 | + °* 2 ^j ' (*')