See the following documentation regarding sharpening in the Scene7 Publishing System (SPS) Help. In Scene7, click Help > Help Contents > Master Files > Sharpening an Image.
See also the following best practices PDF:
Currently, all sharpening parameters (op_sharpen, resmode, op_usm) are applied as specific layer arguments. By default, the sharpening argument applies only to the previously referenced layer content unless a layer=comp argument is included in the URL before the sharpening argument.
For sharpening arguments (or sharpening parameters included in an image format) to apply to an entire layered or template image prefix the sharpening parameter reference. Or, prefix the image format reference with layer=comp.
The more sharpening applied always adds more aliasing. Try some other sharpening options or lessen the sharpening arguments to address it. Any over sharpening causes aliasing.
See the SPS Help for more information: