HAMAR LASER STEALTH Series, Общее руководство по обучению

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106
Close Buck-In
The close buck-in procedure can be remembered by
the rule, “Zero Near, Point Far.” Buck in the laser
beam by zeroing it on the
near
target, and then tilt
the entire laser unit to "point" the laser beam,
centering
on the far target. The two steps are
repeated until both targets show zero readings.
Remote Buck-In
As the distance between the laser and the near
target increases with respect to the distance
between the two targets, bucking in by the close
method becomes nearly impossible. A special
remote procedure has been developed for these
situations. The remote buck-in uses simple
geometry to make the laser beam parallel to the
centerline of the two targets and then centers the
beam on that line. Figure 52 illustrates how the
remote method works.
Unlike close buck-in, where the laser is pointed to zero on the far target, the remote procedure has the
laser point through zero to a point called the "Set Point." The Set Point distance is the offset between the
parallel laser beam and the target centerline.
The uncorrected laser beam, the offset parallel beam, and the set distance form a triangle. The uncorrected
beam, the target centerline, and the distance between the far target center and the far reading form a
second triangle. The two triangles are geometrically identical because they have the same three angles.
Figure 53 - Calculating the Set Point
A relationship between these two triangles can be stated in the formula, “The set is to L1 as the far
reading is to L2.” Stated mathematically, the ratio is Set/L1 = Far/L2. If L1, L2, and the far reading are
known, the set can then be determined by the following formula: Set = (Far reading * L1/L2).
Note:
This is a simplified formula for cases where the laser beam is centered on the near target.
In remote buck-in, point through zero to the Set Point. This means moving the laser until it reads the set
amount on the
other side
of zero from the starting point. In doing so, the sign of the number (negative or
positive) will be reversed. Figure 53 illustrates this by taking sample readings and showing how the Set
Point is derived. (Notice the far reading is a negative number and the Set Point is positive as you go
"through zero.") This results in a laser beam parallel to the target centerline but offset by the set distance.
Figure 52 -
Remote Buck-in