The 8mm video tape format (Video8) was developed in the early 1980's by a consortium of companies and gained traction with the introduction of Sony's Handycam for the Video8 format in 1985. This popular camcorder helped pave the way for Video8 to eventually outsell VHS and Beta camcorders. While the format is not compatible to play in VHS players, it had a superior tape cassette design to VHS and higher quality recording material with a recording medium utilizing all metal tape that was 13 microns thick.
Even with the technical advancements over VHS and Beta, the Video8 format degrades over time just as other analog formats. Although the lines of resolution for VHS and Video8 are about the same at 240 lines, our experience has been that recorded 8mm tapes from the 1980's and 90's tend to retain their colors and overall capture quality better than a VHS camcorder recording of the same age. Fewer dropouts, more color retention, and less chromatic distortion. Which means you can generally get a good digital transfer from Video8 and Hi8 recordings. Hi8 was a more advanced version of Video8 that reached 400 luminance lines of resolution.
With the introduction of Hi8 and market demands to have longer playing/recording tapes that matched or exceeded the 90 minutes on 1/2" VHS tape, a thinner 8mm tape with metal particles (MP) was introduced. This was followed by Metal Evaporated (ME) Hi8 tape that greatly improved electromagnetic characteristics. It also eliminated the use of a binding that is usually part of a video tape. This cutting edge design allowed Metal Evaporated tapes to have low noise and high quality video quality as well as high dynamic range audio using Pulse Code Modulation (PCM).
For aging and preservation, Video8 and Hi8 suffer the same fate as any analog tape including image noise and tape that can become sticky, jamming playback units, or tape becoming brittle and snapping. Because of the smaller size of 8mm tape head drums compared to VHS/Beta, 8mm tape can experience more dropouts. We have seen this more on Hi8 tapes than with Video8, especially with ME emulsions. ME tape tends not to age as well as MP tape due to its lack of binding and possibly from lubricants and anti-corrosion agents used in the ME manufacturing process.