Pro 10 PK white dots print problem

[Ketil Wright]

I use a canon pixma pro 10. I refill the cartridges using the dribble method with the Precision Colors ink set (V2). The printer was bought new about 2 months ago. When the original OEM inks showed low, I drained all carts completely & refilled with PC Ink. I've since refilled 3 times in the ensuing 2 months.

Yesterday I noticed what I believe could be a problem with the Photo Black ink on an output file made by the Canon Color Management tool.

A picture is worth 1024 words:

This image was made by using a macro lens & a flash behind a sheet of Red River Arctic Polar gloss paper upon which I had printed the black rectangle. The print was made from photoshop cs6.

The rectangle is exactly 1 inch horizontal, making the vertical/horizontal space between the offending white dots approximately 0.08/0.05 inches by my calculations.

I never noticed this on any prints of real photos. The only reason I saw it was because I was curious enough to examine the test charts for icc profile generation on various papers with a loupe.

Printing on either Red River Arctic Matte, or Canon premium matte does not show this problem. The photo above was made of Red River Arctic Gloss.

I never generated any of my own print profiles prior to switching to PC inks, so I have no way of knowing if they play any role in the issue.

My questions are:

1) Should I be concerned about this?
2) If so, what should I do about it?

 

[mikling]

The size of the dots relative to the droplet pattern suggest that something more macro is at play. The other thing is the regularity of it. One clue is that it does not occur with other matte papers, so unless you are doing the switch to MK in PK, then the same nozzles are at play since the Pro-10 prints with PK in MK paper settings.

If the rectangle is 1" horizontal then the vertical could be 0.7-0.8 ins maybe. It would take multiple head passes to create this block. Yet, the spaces in between appear consistent in its spacings..especially vertically.

Ding Ding Ding.. Rollers. Now take a flashlight and look into the Pro-10 and peek into the printer from the front and take a look at the rollers and what mates with them and the amount there are. The little pizza wheels. Now line up where the black square would have exited.

Why not matte,.....because the surface is rough and the ink soaks INTO the paper as well.

Why on Gloss, a lot of pigment resides on the surface of the paper. So when the pointed wheels run over the paper, it creates an impression and if the ink is wet, it can lift the ink and create a dot.

Why not on photos? because in most photos, the amount of ink placed on the paper is a lot less than when a solid black patch is called for. With less ink on the paper, it has a chance to dry before the rollers stomp over it. Whereas on a pure black patch, the ink is not perfectly dry before the wheels runs over it and lifts at the contact point.

The effect will vary by paper. One thing to try if you insist on using this paper paper at the chosen setting is to increase ink drying wait time and see if it helps..not I have not used this for a very long time and I can't recall if it is the time that the printer waits to make the return pass or whether it is the time between each page. On an Epson, you would turn off bidirectional or high speed printing.

With dye inks, the effect is commonly just indentations since the ink is under the surface but the paper would be soft from the absorption of ink and commonly called pizza tracks since the fine rollers that grab the paper are like pizza cutters.

Chances are that the measurement will be off only by academic amt because of the missing dots. The profiles will not suffer. I would not worry about it.

FYI as well

http://www.precisioncolors.com/PC72V2ICCs.html

 

[PeterBJ]

Here are the "pizza wheels" from a Canon iP4200. The photo is from a thread about a similar problem.

 

[Ketil Wright]

@mikling Thank you for the explanation, and @PeterBJ thanks for saving me a trip into the printer with the macro lens (which is way too big to fit in there anyway).

Mainly I wanted to be know if this could be a problem with the printhead. It sounds like this is expected behavior.

I was not concerned about the icc profiles I generated, which so far appear to be working at least as well as those pointed to by mikling.

if you insist on using this paper paper at the chosen setting

I'm not sure if by "insist", you mean that you think there is some problem with this paper (Red River Arctic Polar Gloss), or with my settings (although I didn't say what they were). I hope it's not the paper, as I just bought 150 sheets of 8.5x11 & 13x19 during the black friday sale at RR.

I do see that your icc page shows a paper setting of "Photo Paper Plus Glossy II". I used "Other glossy" when I made the profile & later for all prints. Oops, I could have gotten that right if I'd read the RR website more carefully, not to mention the packing slip :-(

 

[mikling]

I did not see an inherent problem with the paper but sometimes different settings might be needed. Typically if I run into a paper situation, I start trying different settings. Different media settings will lay down differing amounts of ink. In the high quality mode, printing is slower, maybe this will help. However, you did mention that you did not notice it on actual photos and only on the target sheet and if this is the case, then I would simply ignore the issue and not worry about it because most images do not contain that pure black that the target lays down. But if one is needed, then a different paper choice might be warranted.

Also consider that temperature and humidity level may also play a part in how the results might turn out as well....in addition to paper batches.