can a nozzle check be wrong?

[Paul W.]

Heresy, I know, but I've seen a few hints here and there. So, accuse me of rumour-mongering!

But is it possible? I've spent a considerable amount of time trying to clear up nozzle checks for my Cyan position. I'm using Paul Roark's Eb6 inkset on a 1400. Using the full arsenal, overnight soaks, shoe-shine under head cleaning, wiper blade, capping station, purges, etc.

The thing is, although the checks for the Cyan (actually 30% Eboni) show many gaps, my photos turn out beautifully, printed in QTR. Here's one test... but it moves around from day to day, which I think is supposed to mean it's air in the system somewhere.

So if I've done all the cleaning (except for the risky push-pull syringe technique), and I get bad checks in the Cyan position, and beautiful prints - could nozzle checks be sending me a mixed message?

Like I say, heresy... but a few other folks have raised this possibility.

TIA,

Paul

 

[turbguy]

Typically, missing segments on the nozzle check print that "move around" between nozzle prints implies there is a non-compressible fluid (air) in the nozzle chambers. This can be very difficult to vent out the nozzle opening, since the piezo mechanism needs a nozzle chamber completely full of an in-compressible fluid to operate (or it won't "spit").

My solution was just let it sit overnight, and try again. Seemed to work. I believe the air in the chamber slowly dissolved into the ink, but that's just a theory...

Why you photo's print fine is somewhat of a mystery, unless the high demand for ink during photo printing is enough to displace any air.

 

[akramjef]

@turbguy is 100% correct . there is air trapped in the printhead .why photo print is good ,because the working nozzle will compensate for non working one . in photo printing the speed become slow but the print head move over the same line several times injecting more ink on the same point which will cover any missing nozzle. but if you print the same photo on plane paper using text and photo setting, you will notice the missing nozzles. do print head cleaning twice then leave the printer to sit over night , this will usually solve the problem, for my printer it took 4 days till i get rid of trapped air doing several head cleaning and printing purge photo.
good luck

 

[The Hat]

although the checks for the Cyan (actually 30% Eboni) show many gaps, my photos turn out beautifully

A nozzle check is never wrong, if it prints with segments missing then you have an ink flow issue,it would be like calling an Elephant in the room furniture, but don't tell him I said that..

Because your using all black inks and the missing cyan segments are not noticeable and may in fact make your print look even better, B&W prints look more interesting with lower LPI when viewed from a distance hanging on a wall...

 

[stratman]

A nozzle check is a snapshot in time. It is what it is. Human interpretation, on the other hand...

 

[Paul W.]

Thanks, all. I should add this photo, showing the pattern a few days earlier. The pattern doesn't seem to change every day... but every few days.

And like some of you here, a friend of mine suggested simply going ahead with my printing... and these "air clogs" may just work themselves out. And to @akramjef, your point on text possibly being affected prompted me to print out a family photo. The photo has a caption, and it printed out fine. However, perhaps even though the caption is text, it may still be a jpg like the photo. (The photo and caption were generated in Photoshop Elements.)

 

[The Hat]

Text outside a Photo is Bitmapped and text in bedded in a Photo is Rasterize and Vector text is Postscript...

 

[Paul W.]

do print head cleaning twice then leave the printer to sit over night

Then do you leave the printer on? or turn it off?

Thanks!

 

[mikling]

If there is little need for the Cyan channel in the images even in the QTR rip, you might not notice it. I don't have the technical manual for the intended printer but some printers only use certain colors/channels depending on the media chosen as well.

If the nozzle check shows missing, it is missing. if the print comes out properly, then the use of that channel was not called for in the print.

 

[turbguy]

Then do you leave the printer on? or turn it off?

Thanks!

Doesn't matter...I leave mine on.