Center Inserted Image Within Range

I am having some troubles inserting an image than centering it within the cell.
When I do this:

Set rng = Target.Cells
With pic
.Height = rng.Height
.Width = rng.Width
.Left = rng.Left
.Top = rng.Top
End With

The picture fits within the borders of the cell, but when I do this:

Set rng = Target.Cells
With pic
.Height = rng.Height /2
.Width = rng.Width /2
.Left = rng.Left /2
.Top = rng.Top /2
End With

The picture is the right size but not within the cell.