[Pupfish]

Sorry, there wasn't any E6 in 1960-- I believe it was called E2 and was a rather altogether different Ektachrome process.

Ektachrome seemed pathetic through 70's and well into the 80's. Will admit that a percentage of my late 70's stuff started bleeding almost immediately, but probably due to reacting to the PVC (vinyl) slide protector pages commonly found back in those days. Yet my Kodachromes of the same era were curiously unaffected by this.

E6 films themselves, and the E6 process had both matured and improved dramatically by the watershed moment of Velvia's launch in 1990. (Vinyl protector pages had already died a swift and ignominious death). Most modern testing comparisons indicate that at least the slow to medium speed Ektachrome and Fujichrome emulsions now have dark storage archiving that's no longer shamed by a severe trouncing from Kodachrome anymore. Too, most all E6 films have projector-cycle/ bright storage lifetimes exceeding Kodachrome projection/bright storage life-- some by a substantial margin.