How do you determined the OT Factor?

How do you determined the OT Factor?

• A. Observer target distance, divided by 1000, expressed to the nearest whole number. If it ends in .5 then express it to the nearest even whole number, if less than 1000 keep as a decimal.
• B. Distance in meters divided by 100, rounded to the nearest ten
• C. Grid distance only
• D. Elevation difference divided by 100

Answer: (A)

The OT factor comes from how far the observer is from the target. You take the observer-to-target distance in meters and divide by 1,000 (to convert to thousands of meters). Then you express that result with a specific rounding rule: if the decimal part is .5, round to the nearest even whole number; otherwise round to the nearest whole number. If the distance is less than 1,000 meters, you keep it as a decimal (since you’d have something like 0.75, not a whole number). Example: distance is 2,350 m → 2.35, which rounds to 2. If distance is 1,500 m → 1.5, which rounds to the nearest even whole number, giving 2. If distance is 900 m → 0.9, keep 0.9. This is why the correct approach uses the observer-target distance divided by 1,000 with that specific rounding, rather than dividing by 100, using grid distance, or using elevation difference.

The OT factor comes from how far the observer is from the target. You take the observer-to-target distance in meters and divide by 1,000 (to convert to thousands of meters). Then you express that result with a specific rounding rule: if the decimal part is .5, round to the nearest even whole number; otherwise round to the nearest whole number. If the distance is less than 1,000 meters, you keep it as a decimal (since you’d have something like 0.75, not a whole number).

Example: distance is 2,350 m → 2.35, which rounds to 2. If distance is 1,500 m → 1.5, which rounds to the nearest even whole number, giving 2. If distance is 900 m → 0.9, keep 0.9.

This is why the correct approach uses the observer-target distance divided by 1,000 with that specific rounding, rather than dividing by 100, using grid distance, or using elevation difference.