canon i960 how long can you print after low ink/out of ink warnings?


Getting Fingers Dirty
Nov 19, 2004
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Enjoying my first evening with my new i960. After many fantastic prints, I've gotten the low ink, then no ink warning for the photo magenta, is it okay to keep printing as long as I can see some ink below the sponge (or in the sponge?) if I'm planning to replace with another cartridge? And how empty can it go if refilling the cartridge? Thanks, Virginia


Printer VIP
Nov 3, 2004
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Bay Area CA
Printer Model
CR-10, i560 ,MFC-7440N

I've wondered about your first question a few times myself... how long can I keep going after I get warnings?

I sent the following questions to Canon:

1) How does the printer measure ink? Does it "guess" by the drops
printed, or does it "visually" see / actually measure how much ink is
2) What increments does the level drop? Do I only see a change when it
is empty, when it is half way, or does it display 1/4, 1/8, 1/32 changes
in the ink level?
3) Any other information about the actual ink measuring / display
process would be excellent!
Thanks in advance!

Here is their reply:

"The Canon Think Tank SystemT uses a combination optical sensor and ink
counters to estimate the amount of ink inside the ink tanks. The
optical sensor can only verify whether ink exists inside the reservoir
or not. When the state of the ink tanks is between 100% and 50%
capacity, the ink level status is determined by the ink counter.

The ink counters estimate the amount of ink left inside each ink tank
based on the ink usage and the purge cycle (the purge cycle refers to
whenever the printer is cleaning itself). When the optical sensor
triggers, this means that ink inside the reservoir portion of the ink
tank is empty and the ink level status should display that 25% of the
ink is available. The remaining ink exists inside the sponges inside
the ink tank.

The ink counters are used to estimate the amount of ink inside sponge
and then will trigger an error message when the ink tank is empty. A
typical problem that may occur is if an ink tank is replaced when the
ink level status displays that the level is higher than 25%. Since the
optical sensor can only determine if there is ink inside the reservoir
and not the intermediate ink level, the ink level status never changes
because nothing triggers that the ink tank has been changed. The ink
level status will probably remain at 50% until the ink inside the ink
tank reservoir empties, then the ink level status will display that 25%
of the ink left and decrement the ink counter as normal.

Since the ink level status is maintained inside the printer and not by
driver, uninstalling the driver will not reset the ink counter. If it
is necessary to reset the counter on a specific ink tank, temporarily
place an empty ink tank in place of the desired ink tank counter that
needs to be reset. The ink level status should display that the ink
tank is 25% full. Replace the full ink tank back into the appropriate
slot and the ink level status should display at 100%. An obvious issue
is that if the ink tank placed into the printer is not full, the ink
level status will still indicate that the ink tank is 100% full. "

Virginia, be VERY careful not to allow your printer to print without ink. The ink acts as a cooling agent for the print heads and if it isn't there, the heads can be permanently damaged. There is some debate regarding how robust the heads are, but personally I like to play it safe.

Regarding refilling, I'm personally a big fan of "topping off" these cartridges when the ink is about 1/8 of an inch from the bottom of the reservoir... just before the warning message pops up. This keeps the sponge always wet with ink which will increase its life and the number of times you can refill it. Also, these cartridges are so very easy to refill, there aren't very many reasons not to top off.

Hope that helps!