2012

Table Of Contents
Scale Raster Images
You can control the size of a raster image in a drawing to match the scale of
the drawing.
You can specify the raster image scale factor when you attach the image so
that the scale of the geometry in the image matches the scale of the geometry
in the drawing. The default image scale factor is 1, and the default unit for all
images is Unitless. The image file can contain resolution information
defining the dots per inch (DPI), relating to how the image was scanned.
If an image has resolution information, the program combines this information
with the scale factor and the unit of measurement of the drawing to scale the
image in your drawing. For example, if your raster image is a scanned blueprint
on which the scale is 1 inch equals 50 feet, or 1:600, and your drawing is set
up so that 1 unit represents 1 inch, then in the Attach Image dialog box under
Scale, select Specify On-Screen. To scale the image, you clear Specify On-Screen,
and then enter 600 in Scale. The image is then attached at a scale that brings
the geometry in the image into alignment with the geometry in the drawing.
If no resolution information is defined with the attached image file, the width
of the raster image is set to one unit. Thus, when the image file is attached,
the image width in units is equal to the raster image scale factor.
Detach Raster Images
You can detach the reference to an image file in a drawing.
You can detach images that are no longer needed in a drawing. When you
detach an image, all instances of the image are removed from the drawing,
the image definition is purged, and the link to the image is removed. The
image file itself is not affected.
NOTE Erasing an individual instance of an image is not the same as detaching an
image. An image must be detached to remove the link from your drawing to the
image file.
Modify Raster Images and Image Boundaries
You can control the clipping boundaries and image display properties of a
raster image.
746 | Chapter 11 Share Data Between Files