Tape length longer than advertised?

[ItIsAScience]

I've been converting tapes for a few friends after doing my own recently and I've noticed a strange trend amongst the Video8 tapes. When they are full, a tape advertised on the box as being 90mins will always hold about 110mins of footage. I've noticed this from multiple people's tapes and for multiple brands but only ever for Video8.

All my Hi8 tapes tend to have enough room to overrun to about 93-94mins but nothing as extreme as 110mins. Seems strange to me that manufacturers would give away free space so I was wondering if anyone knew why this might be.

[lordsmurf]

It may have been temporary, not forever. Production reasons, budget reasons. Sometimes it's easier and cheaper to fill a contract by rebadging better products as worse.

[NJRoadfan]

What format was the runtime quoting? PAL or NTSC? I've come across some discrepancies between the formats and tape length. For example, P5-90 (PAL) and P6-120 (NTSC) tapes are usually filled with the same amount of tape. Sony actually quotes Digital 8 SP runtime as 60mins for both tapes!

P6-120 should have 106m of tape in it and P5-90 should have 112m (PAL runs faster).

MiniDV tapes advertised as 60mins almost always have 63mins of tape in them. Panasonic just labelled all their pro tapes for 63mins in the end.