Scale Units

The status bar and legend ruler display the scale of the image on the screen. You can choose between several different scaling units. You can select Feet-Per-Inch, Meters-Per-Inch, Meters-Per-Centimeter and Ratio scale. To change scale units, select "Perferences->Settings" from the menu bar. Simply click on the appropriate units.

Ruled Scales. Most scale units are associated with a “base unit” such as the inch or the centimeter. When these units are used, a “ruler” will appear in the Legend. If you select Feet-Per-Inch or Meters-Per-Inch, the ruler will be one inch long. If you select Meters-Per-Centimeter, the ruler is two centimeters long.

Ratio Scales. When ratio scales are used, no ruler will appear in the Legend. When you select ratio scales, the scale is given as a ratio such as: 1:1000. This means that every unit on the plot represent 1000 units in real life. With Ratio Scales, any units can be used. You can use meters, feet or inches and the ratio. For example, if the scale were 1:1000, one inch on the plot would represent 1000 inches in the cave. Likewise, if the scale were 1:1000, one millimeter on the plot would represent one meter in the cave.

Windows Scales. Windows scales everything on the screen to be slightly larger than normal. This means that a "one inch" or “two centimeter” scale bar can be much larger on the screen. The actual size on the screen depends on the size of your monitor and the video resolution you are using. Windows does this to make the display easier to read. This does not effect printing. The Viewer always prints exactly at the scale specified.

Scale Units vs. Display Units. Scale Units are different from Display Units. Scale Units are only used for the ruler in the legend and the Status Bar. They are always expressed as a ratio such as feet-per-inch or meters-per-centimeter. Display Units are used to display absolute values like depth, distance or paper size.