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density value and Inches as the density unit. Then it was scaled based on its
paper scale of 1" = 48".
The density units that you select when you insert an image that is not
georeferenced should match the units at which the image was scanned. In
this case, the units are inches because the image was scanned in dots per inch.
NOTE Remember that the scale must be based on the same units. For example,
if the scale in the original floor plan is 1" = 4', you must convert both sides to the
same unit. In this case, convert the 4 feet to inches, which is why you use 1" = 48"
as the scale factor.
Setting Density Units for an Image That Is Georeferenced
The following example shows the relationship between density units and a
georeferenced image. Because there is no paper scale to consider, you can
insert the image using the units that the image represents, such as feet or
miles, and you do not have to scale the image when you insert it.
Georeferenced images include GeoSPOT and GeoTIFF file types, and images
that use World files as their correlation source.
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