Printing uneven, but nozzle checks are negative

[PenguinLust]

...negative, as in, they don't indicate there's a problem. I printed from and it's like some of the nozzles aren't firing sometimes. Then I printed a nozzle check and if you'll ignore the junk on the B-side of that paper that I couldn't remove from the scan, you'll see it came out beautifully. I tried printing the image a couple more times, and it was better, but far from perfect.
So why does my kitteh look so awful but a stupid test pattern came out perfectly?
I also did an automatic head alignment, but that shouldn't have made a difference, should it?

I have an MG6120 and refilled 220/221 carts.

 

[PeterBJ]

The red-orange appearance of what should be grey tones indicates that the complementary colour is missing. The complementary colour of red-orange is cyan, so this indicates an ink flow problem with cyan. This could be caused by the cyan cartridge, or the fine ink channels for cyan in the upper black plastic part of the print head could be clogged. Hopefully it is a cartridge problem. I suggest to try another cyan cartridge, best but expensive is a new Canon OEM cartridge for the testing.

The reason the problem doesn't show in the nozzle check is that nozzle checks use very little ink compared to photo printing, so the cartridge and the ink channels can deliver enough ink for a perfect nozzle check, but when a photo is printed the ink demand increases and the problem shows.

A simple test to show if a cartridge has an ink flow problem is to hold it over a sink and blow gently into the vent. This should cause a couple of drops of ink to exit the ink outlet of the cartridge. Repeat the test with a known good cartridge, for instance the magenta cartridge that seems to have no ink flow problems. If you have to blow harder to exit ink from the cyan cartridge, then that cartridge is the problem.

 

[The Hat]

If you have an ink problem with one of your cartridge then the nozzle print wont pick that up for you,
the nozzle check is only designed to tell you the stare of your print head nozzles and nothing else.

Just looking at the photo of the cat there is definitely an ink flow (Starvation) problem there
but I think its in more than just one of your cartridges;
a possible cause could be a blocked air maze due to over filling !

The cyan is certainly suspect and so might be the magenta,
to see whats causing the trouble youre going to need another cyan cartridge first,
one you know that is in good condition to test in your printer again.

Your current cyan cartridge will need to be purged, dried and refilled again before it can be reused in your printer,
before trying to print the cat again with a new cartridge run a head clean and a nozzle check first
just to make sure that all the nozzle are firing properly.

Do the test that PeterBJ suggested also..

 

[PeterBJ]

The Hat wrote:

...The cyan is certainly suspect and so might be the magenta,...

Like Photoshop, the freeware program Irfan View can also analyse colour channels for an image. Irfan View can only analyse RGB channels, but you can convert the image to negative, do the separation and invert the separated images. This way R will correspond to C, G to M, and B to Y. This will not be accurate as the CMY(K) conversion depends on the printer profile. Converting a colour image to greyscale also sometimes makes defects more easily seen.

Here is the cat converted to greyscale and the CMY part images:

It is clearly seen that something is wrong in the cyan channel and possibly also in the magenta channel. The stripes in the magenta channel could be caused by the RGB to CMY conversion not being accurate, or the magenta cartridge could also be faulty, as suggested by The Hat.

 

[PenguinLust]

Unfortunately, I don't have a known-good cyan cartridge. I was here a while back w/a problem w/my other cyan cartridge, so I swapped it out for the one that's there now. Should I just chuck my cyans and get new ones? Can I get individual CLI-221s or do I have to order a new pack?

 

[jtoolman]

Then you better stop printing any further until you do. Or you night damage the head,

 

[PeterBJ]

PenguinLust wrote:

Unfortunately, I don't have a known-good cyan cartridge. I was here a while back w/a problem w/my other cyan cartridge, so I swapped it out for the one that's there now. Should I just chuck my cyans and get new ones? Can I get individual CLI-221s or do I have to order a new pack?

If your cartridges are Canon OEM, I think they should be cleaned. If they are third party, I think they should be discarded. Third party cartridges may work well if only used once, but often develop ink flow problems if refilled. So only Canon OEM cartridges are recommended for refilling.

You can order one or more cartridges as you like. There is no obligation to buy a complete set if you only need one cartridge, but you might save on postage by buying more than one cartridge at a time.

Precision Colors sell cleaned ready to use empty cartridges: http://www.precisioncolors.com/c6ccart.html .

Instead of the supplied plugs I strongly suggest the use of the zero clearance plugs: http://www.precisioncolors.com/c6cacess.html , as some newer Canon printers have very little clearance above the cartridges. See this thread: http://www.nifty-stuff.com/forum/viewtopic.php?id=8770 . These plugs should be secured with a piece of aluminium tape.

 

[PenguinLust]

Ah yes, OEM... I keep forgetting what I have, but it came from Precision Colors. Do they only deal in Canon OEM? I threw away the supplied plugs and got Octo's flush ones.
I guess I should point out that I use the German refill method, but the first time I fill them, I top fill and then seal the hole permanently.

 

[PeterBJ]

I'm sure that when the website says the cartridges are Canon OEM, then it is true.

There have been some threads about problems with the newer Canon cartridges PGI-x20/CLI-x21 and PGI-x25/CLI-x26 after German method refill. I have the suspicion that these newer cartridges are more fragile than the older transparent cartridges, and that top filling actually is better for the new cartridges. Top filling causes no needle damage to the sponges or sponge displacement.

If you decide to change your refill method to top filling remember to seal the German refill hole with hot melt glue, else the cartridges will leak during refill.

Here are some links to threads about German refill problems with the newer cartridges, maybe you find a useful tip or two?: http://www.nifty-stuff.com/forum/viewtopic.php?id=7915&p=1 , http://www.nifty-stuff.com/forum/viewtopic.php?id=7822&p=1 , http://www.nifty-stuff.com/forum/viewtopic.php?id=7811 , http://www.nifty-stuff.com/forum/viewtopic.php?id=7744 , http://www.nifty-stuff.com/forum/viewtopic.php?id=8208&p=1

Whatever your refill method it might be a good ides to flush your cartridges at the first sign of ink flow problems.

 

[turbguy]

I agree your nozzle test looks good.

Are you printing in low quality or high quality photo mode? It can also be an issue with bi-directional printing, and the highest quality modes should only print in one direction. This might also show up on extended nozzle tests and MANUAL head alignment sheets as defects.

Lie to the printer about the paper type to Matte Photo Paper or High Quality Glossy Paper and see if there's a difference.

Wayne