A method for detecting defects in a product (10), such as food packaging, having a range of thicknesses of cross-section through which detection will take place; the method comprising: scanning the product (10), with for instance x-rays, to identify one or more light regions, and one or more dense regions of the product; and creating a first signal path and a second signal path from a single set of scanning data, and conditioning: the first signal path for detection of defects in the one or more dense regions; and the second signal path for detection of defects (14a, 14b, 14c) in the one or more light regions. Advantageously, detection of defects in the contents (dense region) of a product and the seal (light region) of the product is conducted simultaneously.
