The term “holographic film” can refer to two different products. One is a special kind of packaging film used to add holographs to things like food packaging, while the other is a film designed for the production of holographic images. These two products are quite distinct, require different manufacturing processes, and tend to come from different sources because of their different end purposes. The type of film under discussion is typically clear from the context.
In the sense of packaging, holographic film is a thin sheet that may be backed by cardboard, paper, and other materials, with embedded holograms. These may be used to create more eye-catching packaging or a security measure, as a company can order custom holograms and use these to uniquely identify its products. The film is flexible, and thus can be used in flexible as well as rigid packaging and devices like small stickers or seals.
Companies may use holographic film on a variety of products. Generic lines come with basic shapes like diamonds and stars for companies that do not want or need custom holograms for their packaging. When holographic film is used as a security measure, the package may also include a description, so customers know what to look for when they evaluate the packaging or seals for authenticity. Holographic film seals are common on new electronics and software to help users avoid pirated or aftermarket products.
Another type of holographic film is a film or plate treated with a special emulsion so it can be used in the production of holograms. Several different processes can be used to make the film, and photographers may have a preference based on their experiences with different designs. A special photography setup is required to expose the film to create a three dimensional image. Projecting through the film or plate will generate a hologram suspended in air, if the photography was done correctly. Poor exposures may be blurred or otherwise degraded, spoiling the illusion.
This type of film typically comes from photographic suppliers and hobby companies that specialize in the production of holograms. It is also possible to purchase photography supplies and other accessories for making holograms. The process requires a very steady, controlled environment, without light bleeds, breezes, and other issues that are not usually an issue in conventional photography. Any disturbance during the process can push the hologram out of alignment and blur the finished image.