Returns or sets the contrast for the specified picture or OLE object. The value for this property must be a number from 0.0 (the least contrast) to 1.0 (the greatest contrast). Read/write Single.
Example
This example sets the contrast for the first shape on the active document. The first shape must be either a picture or an OLE object.
Dim docActive As Document
Set docActive = ActiveDocument
docActive.Shapes(1).PictureFormat.Contrast = 0.8