How much more could I have gotten from this cart?

[tony22]

In this thread

http://www.nifty-stuff.com/forum/viewtopic.php?id=5925

I got some good info about Canon 9000 M.II cart priming and advice about when to change carts. Since this was the first Low Ink warning I'd gotten on the printer I decided to see what would happen if I waited until the Empty Cart warning appeared. I pulled and replaced the cart and sure enough it seemed like what was left in the sponge could have fed more than a few more prints. Attached is a pic of how much was left. So for the experts out there - how much further could this cart have gone (assuming some sort of standard color use distribution)?

 

[stratman]

Nice picture of the cartridge. What camera do you use?

When Canon marks a cartridge as empty, there will of course be residual ink in the cartridge. If would be foolish of Canon to increase the risk of print head burnout from ink starvation because the consumer wants to squeeze every usable drop of ink.

To my knowledge, no one in this forum knows in detail how Canon calculates "empty". People have discussed amounts of residual ink - you can weigh a full cartridge, a cartridge marked as empty by the printer, and a purged and dry cartridge and then figure it out approximately.

Canon has allowed for the marked empty cartridge to be overridden, at least in previous printers. The ability to do this is not to assuage refillers, but to allow the user to finish a small printjob or, maybe, to override a mismarked cartridge temporarily. (yes, new OEM Canon cartridge chips can malfunction but may be overridden in order to still be used, at least temporarily) I'm think Canon allows this behavior for the former possibility rather than the latter.

The wrinkle in your request is that what you print determines how much more printing you can squeeze out of the residual ink. Who here knows based on your nebulous "standard color use distribution" modifier? Even if we could divine residual ink amount based on the color density in your picture, no one could know your answer since there is no agreement on your defined standard in this forum AFAIK.

To be safe once the current cartridge has been marked empty, swap in a new or refilled cartridge, or, override and finish the page or photo you wanted to print and then refill or swap in a different filled cartridge.

 

[mikling]

The primary reason why Canon allows override is because Epson lost a class action lawsuit when they disabled printing when there was residual ink inside. In court Epson correctly explained why they err on the conservative side in preventing ink starvation , not because of destruction of printheads, as the micro piezo head is none the worse for it. The reason is because once ink starvation takes place in an Epson and air is ingested, the process of removing the air does not always occur without problems. That means upon insertion of a full cartridge afterwards, a user could end up wasting a large part of a new cartridge in attempting to clear the air out and obtaining a good nozzle check. Despite this, they lost the lawsuit because consumers were being ripped off because of remaining ink. Technical limitations does not matter.

It is difficult to determine the amount of ink inside without a physical analog sensor which would be expensive to implement in a disposable cartridge. The chips simply keep count of the amount of ink SHOULD have been used for printing and then add in a fixed amount per prime/clean/start cycle. The aspect of determining how much ink is consumed in these prime cycles etc is the least accurate because the cartridges are emptied using a common source of vacuum. The amount removed from each tank will vary depending on the relative resistance of flow of each. However, the total removed is constant/ or can be determined. So that means that some tanks will have more or less depending on the relative resistances of the cartridges used. So in the end, the chip count is too inaccurate to be totally trusted and still fulfilling a legal requirement. So they allow further use of the cartridge even when the cartridge says empty because it can easily happen.

After the lawsuitEpson's next cartridge implemented an on-off sensor that truly detected empty but is totally oblivious to how much was actually remaining. I do believe that beyond a certain count, it trips an empty signal regardless of the sensor indicating ink still present.

The picture below will show the contacts leading from the sensor place within the cartridge just at a pickup point leading to the cartridge regulator.
With this setup, a cartridge chip could be showing 20% remaining and then suddenly indicate empty. Conversely the cartridge could go down to 10% remaining and stay there for a long time until the sensor detected no more ink. The detector has the final say in Epson's case.

See that empty area that is untouched by ink?, now you know why the size of the cartridge has no reliable bearing on how much ink is actually inside or can be actually consumed. So for those doing those calculations, do understand your potential folly. Also, ink still remains even when empty.

In Canon's case, the fact that there is no sensor means that they will have to allow manual override so the consumer can "fully" consume the cartridge.
There exists no reliable means of determining how much ink remains inside the sponge, at least not within the context of disposable.

I wonder how Canon would fare with the chipfree cartridges if they were challenged about it. I have forgotten whether once the optical sensor was indicating empty whether or not it would continue to print. If it does not, then a challenge can be raised following Epson's judgement because we know that the sponge actually contains a lot of ink even when the tank/reservoir side indicates "empty".
Now for those who are adept at thinking outside the box, was the introduction of the chip on Canon's side to mitigate the issue I just raised. Was the chip to protect them legally? That is, once the optical system, saw the tank side empty ( but no flag raised on the screen as yet), the firmware would only allow a further fixed use and THEN raise the empty warning. Of course this empty warning would not be reliable for the same reasons and thus they allow the override. You need to step back and think about this and consider the Epson lawsuit.

Additionally for those who have owned Epson printers which had sponge based cartridges like the 1270, 1280, 870 etc. era, the sponge system was the worse for determining the amount ink left and worse yet, as the ink became low, foaming would occur during cleaning and even when it was printing fine and left alone, the foam could pull the ink back in reverse creep to the sponge as the sponge slowly dried and get air into the nozzles. The classic Epson clog. The issue of foaming still haunted Epson until perhaps the current generation of printers sporting the empty sensor. By far however, the classic Epson clogging was a big issue especially with the older printers.

 

[ghwellsjr]

In Canon's case, the fact that there is no sensor means that they will have to allow manual override so the consumer can "fully" consume the cartridge.
There exists no reliable means of determining how much ink remains inside the sponge, at least not within the context of disposable.

The only means that approaches reliable for Canon's chipless cartridges is if the user only removes a cartridge when it registers empty and replaces it with a "full" cartridge. By "full", I mean one that has enough ink in the reservoir to register as not yet low.

See this post for a full description of all the ways things can go wrong with Canon's chipless cartridges.

 

[trcrefill]

To my knowledge, no one in this forum knows in detail how Canon calculates "empty".

in the tank part of the cli-8 type cartridge at the botttom you'll see a triangle like bit of plastic on the inside. looking at it from the bottom of the cartridge it has like 2 little mirrors in it. a light shines into that bit and can work out from the colour reflected from the mirrors whether any ink is in there. look at a full cartridge and youll see the ink in front of the mirror bit, and when empty youll see its clear.

when a new cart is put in the chip resets the ink level,
as you print 'x' number of pages it knocks down the ink levels on a preset ratio of number of cleaning cycles and nozzle firings.
when it says ink low it is guessing from the number of pages printed since new etc.
a small light shines in the cartridge through the little mirror triangle thing and when the ink actually is not in there it will then tell you its empty and to replace the ink cartridge.

 

[tony22]

Wow, what a great bunch of knowledgeable people on this site. I just figured I'd get a couple of guesses at "oh, maybe x more 4x6s", but instead I'm treated to all this historical data and analysis. Makes my engineer's heart glad.

Nice picture of the cartridge. What camera do you use?

Thanks. I used my Canon G9 for this one. It was the one I had closest to me and I just kind of shot from the hip for the pic. What's funny is that for as long as I'd used Epson printers in the past, I've been a dedicated Canon camera user for quite a while. That is, after I stopped using film SLRs and sold off my various Olympus OM bodies and lenses - I loved those beauties. But I've had no reason since to consider changing from my Canon digital gear.

Canon has allowed for the marked empty cartridge to be overridden, at least in previous printers. The ability to do this is not to assuage refillers, but to allow the user to finish a small printjob or, maybe, to override a mismarked cartridge temporarily. (yes, new OEM Canon cartridge chips can malfunction but may be overridden in order to still be

I did get an option to keep printing when I got the Empty cart warning, so the 9000 has this feature.

in the tank part of the cli-8 type cartridge at the botttom you'll see a triangle like bit of plastic on the inside. looking at it from the bottom of the cartridge it has like 2 little mirrors in it. a light shines into that bit and can work out from the colour reflected from the mirrors whether any ink is in there. look at a full cartridge and youll see the ink in front of the mirror bit, and when empty youll see its clear.

Cool.

 

[stratman]

Mikling:

Recognizing your great didactic discussion on Epson, I think it should be reiterated that while the Epson piezoelectric will not burnout due to ink starvation, the Canon printhead WILL burnout from ink starvation after some point. The OP is using a Canon printer, so ink starvation is a critical concept.

I am not sure I have seen your scenario of an empty spongeless compartment and NO flag on the partially empty cartridge. Unless the optical sensor is blocked somehow, the empty spongeless compartment will eventually trigger a partially filled flag. IIRC, people have tried resetting a cartridge that had no ink in the spongeless compartment and the printer eventually, meaning in short order, registered this condition as long as the optical sensor was not defeated in some fashion. To my knowledge, no one has been able to disable the chip ink monitoring function, whatever that comprises, while retaining the optical sensor function. That scenario would provide some nice data.

What I don't remember clearly was what happened thereafter in the above example. For instance, what happened when a previously flagged empty cartridge was reset but no ink was refilled. Did the printer print despite ink starvation?

 

[stratman]

To my knowledge, no one in this forum knows in detail how Canon calculates "empty".

in the tank part of the cli-8 type cartridge at the botttom you'll see a triangle like bit of plastic on the inside. looking at it from the bottom of the cartridge it has like 2 little mirrors in it. a light shines into that bit and can work out from the colour reflected from the mirrors whether any ink is in there. look at a full cartridge and youll see the ink in front of the mirror bit, and when empty youll see its clear.

when a new cart is put in the chip resets the ink level,
as you print 'x' number of pages it knocks down the ink levels on a preset ratio of number of cleaning cycles and nozzle firings.
when it says ink low it is guessing from the number of pages printed since new etc.
a small light shines in the cartridge through the little mirror triangle thing and when the ink actually is not in there it will then tell you its empty and to replace the ink cartridge.

How did you come to the conclusion that the optical sensor marks the cartridge as empty?

Ghwellsjr just posted he blocks the optical sensor. Others have written of their disabling of the optical sensor. All concurred in that the blocked optical sensor did not affect the progression to flagged empty cartridge.

Yours is a conjecture discussed here before as well in that the optical sensor is the primary method of determining the cartridge is empty, while the nozzle sprays, cleaning cycles, print spool data, whatever, is used to warn the user on the volume of ink left in the cartridge up to but maybe not including the final "empty" flag.

One way to guesstimate which system is the master method would be to see if there is a difference in the volume of ink left when the cartridge is marked empty. If the optical sensor is the primary method and the chip the secondary method, then the volume of residual ink would be different if you blocked/disabled the optical sensor and one had only the secondary chip method to rely upon. BUT, if the chip was the master, then blocking the optical sensor would make no final difference in residual ink volume.... unless the chip only kicks in after the optical sensor does its job (whatever that is), which does not seem to be the case since people are blocking the optical sensor function. I'm making an assumption that the sensitivity and specificity of the two ink monitoring methods are probably not the same. One is probably more precise in guaging ink volume, and it is this difference my test would exploit.

Those who know the facts don't seem to be talking... until maybe now???

If you are a Canon insider leaking info... welcome!

 

[IanYY]

@tony

Using refilled CLI-8 carts with reset chips, I find that:

1. When the ink status monitor first shows 2/3 full, the ink compartment is half full.
2. When the ink status monitor first shows 1/3 full, the ink compartment is empty.
So my arithmetic calculates that the sponge holds about half as much ink as the ink compartment.
{My reset carts have only 4 states - full, 2/3, 1/3, empty}

This is very approximate, and I would not like to gamble on its accuracy - I usually refill the carts when the status monitor shows 1/3 full.

And these results may not be the same for original (never-refilled) Canon carts.

Ian

 

[trcrefill]

stratman - that was just the conclusion we came to, i havn't read about people blocking the optical sensor as not been on here that often but blocking the optical is interesting. i used to be a member of a n other refill forum but since they started blanking out company names and charging people to read the helpful stuff i have gone off their website. If i give the people on the other site helpful info then that is what i would like in return, not to help people out and then pay to be helped out. hopefully i can help out here and start to trade hints for any problems anyone gets