What to enter for the scale in Didger entirely depends on what your map X and Y units are. You will need to calculate the scale, and then enter it for the map:

- Calculate the corresponding value for your map units (see below).
- Select Map in the Object Manager.
- In the Property Manager, go to the Scale tab.
- Enter the calculated X or Y scale value. For example, if you wanted 1" = 8000' and your map is in feet, you would enter 8000 to the right of Map units per in. for your X or Y scale.

Example Calculations:

- If your map is in units of feet, then you would simply type in 8000. So Map units per in. = 8000.
- If your map is in units of meters, then you need to do some math. 8000 feet is 2438 meters. So 1"=8000' is the same as 1"=2438 meters, and you would enter Map units per in. = 2438.
- If your map is in units of lat/long, then you need to do some slightly more complicated math. You will need to convert 8000 feet to latitude and longitude.

1 degree of latitude is about 68.703 miles (362751 feet). So 8000 feet is about 0.02205° latitude. Insert this for the Y scale (Map units per in. = 0.02205 for the Y Scale).

1 degree of longitude is 69.172 miles * cos(latitude). So find the latitude of the center of your map and insert it in the equation to find how much 1° of longitude is for your map. So if your central latitude value is 39.5°:1° longitude = 69.172 mi * cos (39.5)

= 365228.16 feet * 0.77162

= 281819 feet

8000 feet is therefore 0.02839° longitude (at 39.5° latitude). Insert this for the X scale (Map units per in. = 0.02839 for the X Scale).

*Updated: October 5, 2016*

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