The Invert Photo Negative filter
You can use the Invert Photo Negative filter to invert the colors of an image. This filter is useful for turning a positive image into a negative, or to make a positive from a scanned negative.
The Invert Photo Negative filter
To invert the photo negative of an image
Select an image file.
On the Window menu, click Image Editor.
Click the Invert Photo Negative filter.
In the Invert Photo Negative dialog box, click OK to invert the image.