Canon Pixma 620 Loss Again Of Magenta Weak Cyan

To me there still looks to be a problem with magenta. Regular magenta seems OK in strength but with some clogged nozzles. The medium strength magenta seems too weak and the light magenta is almost missing. I know that different scanners see colours differently and some adjustment of settings is often needed to get a good scan of a nozzle check. But note the green tint of the "CCCMMMYBK" lettering that ought to be various shades of neutral grey.

Here is a nozzle check showing a magenta ink flow problem and green discolouration of the lettering. It was made when troubleshooting this problem: http://www.printerknowledge.com/threads/canon-mp540-strange-magenta-inkflow-problem.6904/ , click to enlarge:



Both a cartridge problem and a print head problem could cause the intermittent error. To rule out a cartridge error I, like The Hat and stratman, strongly suggest trying a new OEM magenta cartridge, to reduce number of variables. Compatible cartridges may or may not work perfectly, so they are not ideal for troubleshooting.

I think a clog in the fine channels in the upper part of the print head, from the ink inlet to the nozzles, could also cause the error. I also think that worn rubber gaskets at the ink inlets could cause such an error, so you could try interchanging the rubber gaskets from magenta and for instance photo black or yellow to see if the error now affects black or yellow. Do the cartridges click firmly in place or are they a loose wobbly fit?

PeterBJ said:

To me there still looks to be a problem with magenta. Regular magenta seems OK in strength but with some clogged nozzles. The medium strength magenta seems too weak and the light magenta is almost missing. I know that different scanners see colours differently and some adjustment of settings is often needed to get a good scan of a nozzle check. But note the green tint of the "CCCMMMYBK" lettering that ought to be various shades of neutral grey.

Here is a nozzle check showing a magenta ink flow problem and green discolouration of the lettering. It was made when troubleshooting this problem: http://www.printerknowledge.com/threads/canon-mp540-strange-magenta-inkflow-problem.6904/ , click to enlarge:

View attachment 106

Both a cartridge problem and a print head problem could cause the intermittent error. To rule out a cartridge error I, like The Hat and stratman, strongly suggest trying a new OEM magenta cartridge, to reduce number of variables. Compatible cartridges may or may not work perfectly, so they are not ideal for troubleshooting.

I think a clog in the fine channels in the upper part of the print head, from the ink inlet to the nozzles, could also cause the error. I also think that worn rubber gaskets at the ink inlets could cause such an error, so you could try interchanging the rubber gaskets from magenta and for instance photo black or yellow to see if the error now affects black or yellow. Do the cartridges click firmly in place or are they a loose wobbly fit?

Click to expand...

See what you mean PeterBj but the original has not transmitted very well. I have the original in my hand and all 3 cyan/magenta stripes are well defined and the text is the grey. I tuned it up a bit in Navigator but it certainly looks a lot weaker in my post. Will try another enhancement program and try and post a better picture. Also note your comments about the gaskets and the cart fit. I have always thought the canons lock was a lot lighter than HP and you can easily dislodge a cart when removing/inserting another.

I had a good look at the nozzle check again and the magenta does have a number of dead spots
in it and this is also reflected in the “CCCMMMYBK” lettering which are green..

The image from barfl2 does appear to have defects. Are these scanning and JPG resolution errors? Actual defects? OP seems to say the nozzle check is good. Does he know what good means? I would hope so.

Looking at OP's last nozzle check, and without any enhancement other, it appears there are evenly spaced horizontal lines in topmost and most dark Magenta. If this is true then the logic board is most likely kaput. A somewhat similar effect can be seen at the bottom of the BK horizontal bar. I have seen this before on other people's nozzle checks and they have claimed their print outs are perfect and that it is related to scanning and/or conversion to JPG.

The light color intensity of the Cyan and Magenta second and third horizontal bars may or may not represent an issue if OP's statement on things looking good is accurate and the issue we note is due to scanning and/or JPG conversion.

There also appear to be small horizontal linear deficits near the bottom of the solid vertical black bars of BK, M, and C. There are also some shading differences in these bars for C and M.

Concerning PBBK - There are two missing nozzles top center and one potential partial nozzle issue 4th row, 3rd column. This is a cursory exam and more issues may be present. Continued printing and/or soaking may cure this.

Other than the PBBK deficits, the others issues remarked on may be scanning/JPG issues and OP's nozzle check may be good as he claims.

stratman said:

Other than the PBBK deficits, the others issues remarked on may be scanning/JPG issues and OP's nozzle check may be good as he claims.

Click to expand...

Stratman click on the nozzle image to get a much better resolution of it..

The Hat said:

Stratman click on the nozzle image to get a much better resolution of it..

Click to expand...

I did.

Not sure what you did with your image but I examined the OP's as is.

Read again what OP said about his nozzle check and study his image. Then read what I posted again including the first paragraph caveat. Until certain potential discrepancies are resolved in what has been written vs images posted then I believe my post is accurate as can be.

If OP understands what a proper nozzle check constitutes then the image has artifacts and little to no true deficits (except for the Pigment Ink nozzle check pattern as discussed).

I do not know how The Hat was able to enlarge/emphasis the defects but it took me a size 5 magnifying lens to see them. Other nozzle checks since, more or less confirm the position of the Magenta missing nozzles? I assume. I could only find 1 small one at the right hand end on the cyan near the bottom. The lettering to me with magnifying still looks grey. The missing two on the PGBK are now there. I also note the BK whilst pretty good is not in a straight line on the bottom row it seems broken up into a number of segments. What does this signify?

My last effort was to get cyan back which I have done and next time I may refill that cart and not use one of my spare re-filled ones. I looked at some old nozzle checks from 2012 and these defects highlighted by The Hat and others were not present.

The next debate do I soak the head for an extended period as suggested by stratman which might or might not improve the magenta situation.

barfl2 said:

I also note the BK whilst pretty good is not in a straight line on the bottom row it seems broken up into a number of segments. What does this signify?

Click to expand...

This is normal. Using a magnifier you can see the individual nozzles. As the printer is capable of bi-directional printing each nozzle set is double. This is most visible with the BK where you can see the individual dots using a magnifier. A print head alignment might minimize the unevenness.

An extended nozzle check from service mode is better to determine if print head defects are present. Here is a link to the service tool thread: http://www.printerknowledge.com/threads/canon-service-tool-v2000.6615/

When running one of the service tools after the printer has entered service mode, Windows might try to install a driver for the printer. You can cancel this install, it only installs a copy of the printer, or you can delete the copy after you have finished using service mode. Note that wireless printers need a USB connection for the service tools to work, they do not support wireless connection.

But be careful with the service tool, and do only print the test print and the EEPROM info. You don't want any resets or region changes.

Attached is my usual test of colours missing after cleaning/nozzle tests. It is a standard picture from Windows library of a high quality. This was printed on HP premium photo paper. I have looked at it with my magnifier and cannot find any faults. I accept that from the last nozzle post there appears to some nozzles blocked, yet this print seems to indicate that they are not serious enough to cause performance issues.

Obviously I will keep a close eye on the situation, and view my nozzle checks more carefully in the future

If you happy with your current output then that’s all the matters and it should work indefinitely for you,
but you will have to keep using high quality mode to mask those missing nozzles.

Here is an enlargement of your flower to show you that it is affecting the overall quality of your photos.