You can also use a custom Code Stage to capture the image. This code uses System.Decimal and System.Drawing.Bitmap namespaces (reference in the Initialise page) to capture an image:
Screen_Image = GetScreenBitMap(X, Y, W, H)
Inputs: X, Y W and H as integers. X & Y are initial start point coordinates, W = width in pixels, H = height in pixels.
Output: an Image data type.