The Target button in the toolbar View group of the Setup Window redirects the 3D camera to point towards the center of the currently selected tumor's base. The effect of this is that 3D camera will appear to rotate around the tumor base instead of, for instance, rotating around the center of the eye.
To obtain the best possible view of the tumor base, use the Tumor # base button in the Camera Location window to rotate the camera viewpoint itself so that the camera is looking through the tumor base towards the center of the eye.
Before clicking the Target button the camera is centered on the intersection of the axes at the origin of the eye coordinate system. Rotations of the camera viewpoint appear to rotate the entire eye model around its origin.
After clicking the Target button the camera will be centered on the center of the tumor base. The camera viewpoint remains at its current location. If the axes are currently unlocked (see Setup Menu) then the axes will shift to the current target point. If the axes are currently locked to the eye center (the default condition) then the intersection of the axes will remain at the coordinate origin of the eye as illustrated below. Rotations of the camera viewpoint will now appear to rotate the model around the center of the tumor base rather than the center of the eye.
After setting the camera's viewpoint in the Camera Location window to Tumor # base, the camera viewpoint rotates around the eye so that it is looking through the tumor base towards the center of the eye. Rotations of the camera viewpoint will continue to rotate the model around the center of the tumor base. Note: the plaque has been removed from the illustration below to reveal the tumor base.
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