Check Canon Cli-8 ink level without removing cartridge

[OpaPiloot]

In reply to Tin Ho:

You state in the same paragraph "The printer never detects ink level low, high or full. There isn't any mechanism there to do such detection" and "There is an optical sensor in the printer which can detect emptiness of the ink cartridges. When a cartridge is completely empty it will be detected by the sensor."
Both statements cannot be true at the same time.

If you refill an unmodified empty cartridge, the optical sensor detects that the cartridge is no longer empty and the printer displays an associated message.

Removing the light guide disrupts the working of the optical sensor so that the printer reacts as if the cartridge is empty, no matter how much ink it contains.
It is my experience that my ip4200 printer eventually reverts to the "low ink level" behavior. So no warranty warning, etc. and no shutting down of the LED.

I think if you understand the above, anybody will.


In reply to pharmacist:

Since checking the inklevel with a modified cartridge is a snap. I am not interested.

Have fun, Bert

 

[Tin Ho]

In reply to Tin Ho:

Both statements cannot be true at the same time.

Removing the light guide disrupts the working of the optical sensor so that the printer reacts as if the cartridge is empty, no matter how much ink it contains.

Sorry, I did not make it too clearly. It is a well known fact that Canon printers do not use any mechanism to look into ink tanks to measure how much ink there is in them. However there is a mechanism, an optical sensor mechanism, which is used to detect emptiness of ink tanks. Canon printers that use BCI-6 series ink cartridges often give inconsistent ink level status becuase the printers do not actually measure ink level in the ink tanks. Rather they estimate, by counting nozzle firings, ink usage and display ink level status based on the estimate. Canon printers that use CLI-8 are pretty much the same but they remeber the estimate and store such data in the chips on the cartridges. The printers still do not use any sensor to measure ink level in the ink tanks.

But these Canon printers all have an optical sensor to see into the ink tanks to determine if any of them is empty. This sensor can only tell if there is ink or not in the ink tanks. The sensor does not know how much ink there is in the ink tanks. This sensor shines a beam of IR light into the bottom of the cartridges. There is a prism at the bottom of each ink tank. This prism will reflect or not reflect the IR beam back to the sensor depending on if there is ink in the ink tanks. This mechanism does not use the light pipe on the cartridges. If you unplug a cartridge and look at the bottom you can see the prism at the bottom of the reserve tank.

The light pipe is for the LED on the back side of the chip on each ink cartridge. The optical sensor is on the left front corner of each Canon printer under a small device covered by a small piece of sheet metal with small openings for IR light and sensor. Each time the print head carriage moves to the left side of the printer the sensor gets to see through the bottom of every cartridge. If any of them is empty it will be detected. But this sensor does not actually measure the amount of ink in the ink tanks. It can only tell if any ink tank is empty or not.

So back to the original thread, removing the light pipe should not cause any change to the ink level monitoring, which is really kept in the chips. The only benefit of removing the light pipe is for visual inspection of ink level by you without having to unplug an ink cartridge. The light pipe blocks the view of ink level in the tanks. Being removed you can see the ink level without removing the cartridges.

 

[OpaPiloot]

Tin Ho
I never disputed the function of the chip. I was aware of the function of the prism.
However, I don't see the relevance of your remarks regarding the original thread, because you ignore the fact that my ip4200 does not respond in the regular way when confronted with a refilled cartridge with a missing light guide.
It seems that the light guide has soime fundtion, because removing it causes the printer to behave differently in this case.
I wonder if other people have the same experience.
So the question is: what is the function of the light guide?

In the mean time, the printer still indicates "low ink level" for this cartridge, it works normally with the 3th party ink and I can easily check the ink level.

 

[Tin Ho]

OpaPilot, your ip4200 is behaving in the regular way. It is still in the state of low ink level only. Soon you will see the chip telling you that the cartridge is empty, despite that you have refilled it. Just wait and watch your printer reaching that point. You will be convinced by yourself if the light guide has some hidden function in it or not.

 

[Smile]

Tin Ho
I never disputed the function of the chip. I was aware of the function of the prism.
However, I don't see the relevance of your remarks regarding the original thread, because you ignore the fact that my ip4200 does not respond in the regular way when confronted with a refilled cartridge with a missing light guide.
It seems that the light guide has soime fundtion, because removing it causes the printer to behave differently in this case.
I wonder if other people have the same experience.
So the question is: what is the function of the light guide?

In the mean time, the printer still indicates "low ink level" for this cartridge, it works normally with the 3th party ink and I can easily check the ink level.

How long does your printer remain in the low ink level? How many times you refilled the cartridges?
You could make a few deep cleanings if you have cheap ink and I'm sure you will get an error telling you that either you disable cartrige monitoring feature or use OEM ink.

If you have been refilling for a long time and the printer did not disable ink monitoring features because you never removed the cartridge that's a good thing, but I don't belive Canon would leave such a stupid back door because their investment into chip market could not be overcome by simply not removing cartridge, but keep refilling it.

I wonder what happens if you pull the plug on the printer then remove the cartridges to refill would it know you removed them or not? And would monitoring feature still work like you claim.

 

[Smile]

Simmilar thread here http://www.stevesforums.com/forums/view_topic.php?id=581825&forum_id=40

 

[Tin Ho]

Smile, that is a very strange post in that forum. First I am not aware that ip3300 was in the market two years ago. Ip4200 came out about 2 years ago but ip3300 was much later than the time frame when ip4200 came out.

The 2nd weird thing about it is when ink is injected through a rubber plug with air tight sealing it will put a lot of pressure into the cartridge from the reserve tank. The entire volume of air in the reserve tank has to be forced out into the sponged chamber. I can't believe ink will not be forced out through the print head below. Some of the air will be released from the vent at the top of the sponged chamber but there is nothing there to stop ink from flowing downward to reach the print head and comes out of the print head.

The 3rd question is that the post is saying the printer can read how full the ink cartridge is. But that is really not true. In fact I am not aware of any desktop inkjet printer of any brand chipped or not that has any ability to physically measure ink level of ink cartridges. Ink level is by all inkjet printers based on counting nozzle firings and based on the count the printer makes an estimate of ink level. I doubt you can keep topping up the ink cartridge without ever removing it to fool the printer. It's too good to be true.

But you never know. Maybe that is not a fairy tale. It is something that will take some time to clarify.

 

[ghwellsjr]

Tin Ho, I think if you re-read the post you will see that the writer does not simply inject ink into the cartridge while it is still in the printer, rather, he starts by inserting the needle of an empty syringe into the air at the top of the reservoir and pulling a partial vacuum on it. Then he removes that needle and then injects the ink from another syringe into the cartridge. He probably repeats this process several times so as to not ever put a positive pressure inside the reservoir.

 

[OpaPiloot]

Pictures:
http://members.lycos.nl/dmjbijzboek/Electronics/CLI-8-inklevel.jpg
Top: CLI-8 cartridge with light guide cut away
Bottom: checking the ink level is easy now

 

[pharmacist]

I discovered something strange today: I tried to see if my resetted cartridge works in my IP5200 printer by exchanging my CLI-8 yellow cartridge (the original one was low according to the ink level status) by one refilled and resetted by me and it shows full now, but when I changed back the ink level by the ink level status still shows full and I tried to print several pictures until the ink tank was empty.

Hey: the ink level still shows full, that's very strange: this mean there is no feedback by the prism to work in conjunction with the chip or is the ink level status got upset by changing the carts.

Oh: for the one interested, for the older models you can reset the cart and use it in the same printer again and again until the cartridge and/or chip wears down. Only the latest printers with "improved" firmware will give problems (probably the ones with a lot of cash back when buying original cartridges). The latest MP830 and probably MP970 should have problems with resetted cartridges used again in the same printer, forcing you to exchange with other carts.