It’s no secret that changing your printer ink when you’re prompted to is as pointless as changing your oil every 3,000 miles. When we took a look at how much printer ink was left in empty cartridges back in 2008, we found supposedly dead cartridges had anywhere from eight to 36 percent of their ink left.

Seven years later, not much has changed.

Bellevue Fine Art Reproduction, a printing company in the Seattle, Washington area, recently published a video on YouTube showing that a pro-grade Epson 9900 series printer had as much as 20 percent of its ink left in the tank when officially empty, as first reported by ArsTechnica.

Epson was not available for comment at this writing, but we’ll update this post if the company responds to our query.

UPDATE: Epson has responded with the following comment clarifying how the 9900's ink system works:

"The Epson Stylus Pro 9900 printer is a graphic arts printer designed for professional operation for printing high value photographs and fine art reproductions on canvas and other specialty media up to 44 inches wide. Like Epson’s other graphic arts printers, the Epson Stylus Pro 9900 is finely calibrated to consistently deliver extraordinarily high print quality.

For quality assurance, the Epson Stylus Pro 9900 ink system uses two methods to track ink levels. The first system estimates ink consumption by mathematically calculating how much ink is consumed from a cartridge for each ink droplet fired during printing and print head cleaning. The printer and ink cartridge use this information to display ink levels and initiate an “Ink Low” status alert. This alert is an indicator to the operator that it is time to consider ordering a new cartridge and occurs with roughly 10-15 percent ink remaining. 

After “Ink Low” alert, the printer can continue to print normally until all usable ink in the cartridge is consumed and noted with an “Ink Cartridge Expended” notice. This “Ink Cartridge Expended” notice is triggered by a second method – a physical sensor in the cartridge – not an estimated amount. The sensor triggers when ink volume has declined to the point that further use could cause harm to the print head.

If a cleaning cycle is initiated during the “Ink Low” status and the level of ink remaining in the cartridge is estimated by mathematical calculation to be less than required for a print head cleaning, the printer will signal that there is “not enough ink to complete the process.” The ink required for cleaning is conservatively estimated to assure there is enough ink to completely eliminate any print head obstructions and ensure quality output. At this stage a fuller cartridge needs to be installed to complete the print head maintenance. But, it is important to note, that after this maintenance cycle, the original cartridge may be reinserted and used until “Ink Cartridge Expended” status is reached. It does not have to be discarded.

Thus, the printing system of the Epson Stylus Pro 9900 is conservatively designed with two methods of tracking ink levels. The “Ink Low” signal does not prevent the ink from being used until the “Ink Cartridge Expended” signal. In the event that a print head cleaning is attempted after an “Ink Low” signal, the professional operator may have to swap in a full cartridge for cleaning and use up the useable ink in the original cartridge at a later time."

Throwing out ink-loaded cartridges is bad enough when you’re buying refills for consumer-grade inkjets for $25 to $50. But when you get into high-end printers like an Epson Stylus Pro 9900 you’re looking at a machine that loads eleven cartridges at once, and each costs more than $200.

Bellevue Fine Art says it loses hundreds of dollars in wasted ink every month, and so far it says Epson hasn’t been receptive to complaints.

The reproduction company came to its conclusions by weighing full cartridges. Then they weighed them a second time once they were “empty” and divided the difference by 1.08—the weight in grams for one millimeter of ink, acording to Bellevue Fine Art.

The impact on you at home: Owning an Epson 9900 is an expensive proposition and only makes sense for businesses requiring high quality printing. Nevertheless, Bellevue Fine Art’s story serves as a reminder that just because your printer says an inkjet cartridge is empty doesn’t necessarily mean that’s the case. In fact, if you print a lot of pages every week you could end up throwing away hundreds of dollars by the end of year. How far you want to push your cartridge past the “empty” point is up to you, although you should also take into account any warnings from the manufacturer about doing so.