Changing the Annotation Automation Pen Highlight Color
(Document/Medical only) The default highlight pen has a COLORREF value of 0xFFFFFF (white). This color will not work well with images that have many mid-range gray colors. A better selection for such cases would be 0xC0C0C0 (silver).
When working with automated annotations, change the color of the pen that is used for highlighting and selecting by setting the AnnAutoHilightPen property for that automation object.
To change the highlight color back to the default color after changing the highlight color, you must set the AnnAutoHilightPen property, using a COLORREF value of 0xFFFFFF.