These tests were done by many different organisations, mostly during the time of multi-colour cartridges - like the 5 colour cartridge in the old 1290.bms wrote:Which?, the consumer magazine, ran some tests a few years ago and found that an Epson cartridge could hold up to 38% of it's ink when the chip reported it as being emptyOn one of the models that told me my ink cartridge was empty, I actually dismantled the cartridge and it was still a third full of ink
One particularly test was done against the Picturemate, which had an all-in-one 6-ink cartridge. These results caused such a stir in the US that a class-action suit was made against Epson.
The trouble is that these figures don't tell the whole story.
Epson cartridges were always intended to have some ink remaining in them because of the problem of drying/clogging printheads. Yes, Epson could let you use all of the ink - but if that resulting in destroying the printhead so you throwaway the printer, was it really worth using that last bit of ink?
Some tests were done on single-ink cartridges which proved this. A cartridge that's said to contain 11ml of ink actually contained 13ml of ink. The 11ml claim was of "usable ink", not physical ink. You always got to use what you paid for. What's left is excess to preserve the printhead - not waste that you paid for.
People who read the Which? type tests complained that ink was being wasted, with the most common outburst being "I paid for the ink, I should be able to use it!" But that's not the case. You're paying for 11ml of ink. If the cartridge has 2-3ml more ink in it to save the printhead, then it's not usable ink. You're only paying for 11ml, not 13-14ml.
The Picturemate case brought it all to a head because, when one colour ran out, all the other colours still had significant ink left. That's where the 38% figure came from.
The thing is that that doesn't tell the whole story either. The Picturemate cartridge was intended to produce 100 prints - that's why it was sold with 100 sheets of paper. In the real world, you would easily get 135 pictures (you'd have to buy extra paper). That's 35% *more* prints than intended. And, even after that, you can still print more. You're getting what you paid for - more than what you paid for, regardless of how much ink might be left afterwards.
I did my own tests on a Picturemate and tended to get around 150 prints before the cartridge registered empty. Yes, there was still ink left in the other colours (that agreed with the 38% wasteage figure) but I was getting 50% more prints than I'd bought anyway, so what had I lost? Nothing.
People are very quick to jump on Epson because there's some ink left in the cartridge, but the argument does not stand up to examination. You always get to use what was intended, you always get what you paid for, and often you get more than what you pay for. So what if there's ink left over? That's intended to preserve the printhead, not to print with.
