There are a number of different 8mm film and video formats, none of which can be easily adapted for viewing by a video home system (VHS) tape player. Since each of these formats uses different technologies, there are no direct, physical adapters from one to the other. The first 8mm film was introduced in the early 1930s and saw a number of revisions throughout the years. 8mm video format, known as Video8, arrived in the 1980s and was succeeded by Hi8 and Digital8. The tape width and encoding used by Video8 formats differ from that used by VHS cassettes, which precludes the existence of a VHS adapter for 8mm tapes.
The older 8mm formats use film, so it is readily apparent that they function in a radically different manner from magnetic tape cassettes like VHS and 8mm. Home movies recorded in the various 8mm film formats can be transferred to newer media like VHS and digital versatile disc (DVD). The VHS adapter for 8mm in this case is typically a device known as a video box. These devices are often designed to project an old 8mm film image into the lens of a modern camcorder, though difference in frames per second (FPS) between the different formats must be taken into account. While it may be possible for a hobbyist to convert their home movies with the right equipment, there are often professionals available to accomplish the task.
Despite using similar magnetic media, there is also no such thing as a VHS adapter for 8mm video cassettes. VHS cassettes use tape that is 1/2 inch (12.7 millimeters) wide, while Video8, Hi8 and Digital8 cassettes all have tape that is about 3/10 inch (8 millimeters) wide. They also use different encoding formats, so any direct VHS adapter for use with 8mm video cassettes would need to decode and encode the information stored on the tape in real time. This can be contrasted with the VHS-c format, which uses tape that is identical in width to the larger VHS. Despite a similarity in size between 8mm and VHS-c cassettes, the fact that the 8mm tapes have a different width and encoding means they are not interchangeable.
Like 8mm film, the only real VHS adapter for 8mm video involves a conversion from one format to another. This may be accomplished relatively easily with a 8mm camcorder and any VHS recorder. Most camcorders have video and audio outputs, which can be connected to the inputs on a video cassette recorder (VCR). It may then be a simple matter of recording the 8mm videos onto VHS cassettes.