Changing Image Display Size

Main window

The image display size is an important parameter. When you trace an anatomic structure, the magnification of the image on which you are tracing will have an effect on the precision with which the digitization is saved--bigger images produce greater precision because the traces are digitized in units of display pixels at the time the trace is created (or most recently modified). Consequently, it is important to choose a particular magnification that is appropriate for a given structure and use it consistently across subjects.

To change the magnification of the main display:

If you magnify an image to a size that is too large to be completely displayed, you can use the scroll bars to move the display area around. Alternatively, you can drag the lower right hand corner of the control panel to make the window larger.

Important note:The true magnification is not necessarily exactly equal to the magnification that you specify--the actual magnification is chosen to give a new image size in whole voxels. This means that the magnification of the display's x and y axes may be slightly different from one another. To review the size of the voxels in the main display, press down the "Voxels" menu. The dimensions of the current display (in voxels), the sizes of those voxels, and the field of view (FOV) are shown in the menu

Orthogonal windows

The magnification of the images in the orthogonal windows is controlled separately

To change the magnification of an orthogonal view window:

  1. Click on the window
  2. From the "Orient" menu associated with the orthogonal window, select the "Magnify" item and pick one of the preset values from the submenu

Note that making the orthogonal view too large can lead to slow performance when the orthogonal views are updated

Back to main Tracer page ©2001 Roger P. Woods, M.D.

Modified: December 15, 2001