with the following message: , the website returns a 404 error. , the website redirected to Hewlett-Packard's homepage. , HP Desktop PCs Customer Support still has an article of instructions and FAQ about LightScribe. Mode of operation The surface of a LightScribe disc is coated with a reactive dye that changes color when it absorbs 780 nm infrared laser light. The etched label will show no noticeable fading under exposure to indoor lighting for at least two years. Optical media should always be stored in a protective sleeve or case that keeps the data content in the dark and safe from scratches. If stored this way, the label should last the life of the disc in real-world applications. LightScribe labels burn in concentric circles, moving outward from the center of the disc. Images with the largest diameters will take longest to burn. LightScribe is monochromatic, initially a grey etch on a gold-looking surface. From late 2006, LightScribe discs are also available in various surface colors, under the v1.2 specification. The etching is still in shades of grey. It is not possible to replace a LightScribe label with a new design (as in erase the surface of the disc), but it is possible to add more content to a label that has already been burned. The center of every LightScribe disc has a unique code that, together with a sensor in the drive, allows the drive to know the precise rotational position of the disc. This, in combination with the drive hardware, allows it to know the precise position from the center outwards, and the disc can be labeled while spinning at high speed using these references. It also serves a secondary purpose: the same disc can be labeled with the same image multiple times. Each successive labeling will darken the blacks and increase image contrast (see drawbacks). Successive burns are perfectly aligned. Drawbacks Special storage precautions are necessary to prevent LightScribe discs from fading. HP's LightScribe website warns users to "keep discs away from extreme heat, humidity and direct sunlight", "store them in a cool, dark place", "use polypropylene disc sleeves rather than PVC sleeves", and also notes that "residual chemicals on your fingers could cause discoloration of the label image". Such chemicals include common hand lotions and hair care products. Users not observing these precautions have reported LightScribe discs to become visibly faded within two months in the worst