Canon i960 Banding Issue

[turbguy]

Here's an extended nozzle check. The grid patterns look flawless. The color bars and the grey patch are streaked. See below. See the black patch in particular. Any thoughts??

 

[turbguy]

I just looked REALLY carefully at the black bands on le left anf right sides of the grid pattern. It appears that these are composed of short horizontal line segments from individual nozzles. There aren't any nozzles "missing, but it appears that the spacing between some neighboring lines is "off pitch" on an evenly-spaced, repeating pattern.

Could there be a problem with the paper feed part of this printer, where it doesn't advance the correct distance between "swipes" of the printhead?? And THIS is what's causing the streaking??

 

[Trigger 37]

turbguy, Thanks for the color print tests. They do look very good but Grandad35 suggestion of printing the Service test print is a better test. I forgot that your printer does not print the normal nozzle check which tests each nozzle. I would any more judgement until we see the Service test print, but I expanded the color bars and I can see very small streaking in the magenta and the photo cyan, but the dark cyan looks good. I am beginning to think the problem you have with photos is a very small amount of ink starvation. The nozzle test use such a small amount of ink it is no stain on the ink carts. Like I said before sustaining ink flow on a large area is a lot more difficult. You didn't mention that you tried some new ink carts. If you have refilled those old carts 10 or more times, they may not be clogged, but for sure they are not supplying ink as good as they should.

 

[turbguy]

I have never refilled carts, I have only used OEM new carts since I aquired this printer new several years ago. I think I'll give it a try later after reading all the success other have had on this forum.

What is a "service test print"? I printed and posted the "extended nozzle check" using the power and resume buttons per Grandadf35's suggestion. Are they the same thing?

What about a paper feed issue as root cause?

 

[Smile]

Let me try than again (darn resizing...) with a smaller image size.

[url]http://www.nifty-stuff.com/forum/uploads/thumbs/2540_dscn8743_1.jpg[/url]

have tried to clean the golden contacs on printhead itself with eraser or apiece of paper, with paper it will turn dirty (evidence that contacs required cleaning). Do the same with printer side with paper only very carefully.

 

[Trigger 37]

Turbguy,... sorry I must of gotten your post confused with another one I read. I had though you said you had refilled the carts 10 times. I re-read your original post and it did not say what kind of ink carts you are using. It would help to know that. Also, I re-looked at your original photo and expanded it as much as possible. There are a lot more clues in that photo. You can clearly see the banding in the blue on the far left as it moves to the right. If a nozzle is clogged it can not make that kind of print. If it is clogged, it won't change in the middle of a print, especially after all that you have done to clean the printhead. So the answer is some kind of ink starvation, or bad ink flow from the current set of carts. This is the third time I've asked you if you have changed the ink carts. I does not matter if you think you are using a new one, not all of them come out of the box working great. Yes the nozzle checks see good but again that is just telling you there is no clog. Get some new ink carts and try it again.

Also, the extended nozzle check described by grandad35 is actually the Service test Print. If you did print that you need to look at it very close with at least a 5x magnifying glass. This will show you in detail if there is any clog on any nozzle as each of them print one line at a time.

 

[on30trainman]

One thing I haven't seen mentioned here, unless I missed it - printhead alignment. Wouldn't hurt to try it.

 

[Trigger 37]

turbguy, you must have been posting the Service test print at the same time or just before I posted my last entry. I did not see your Service test print until just now. The problem is that it is too faint to actually see any details. What we normally do is apter printing the pattern, we scan it into the PC and using some program like Microsoft Picture Manager, we enhance the photo to increase the contrast and colors just to make it easier to see. It does not matter how off the colors are, just so we can see what each nozzle has printed. If you could, take the scanned image and enhance it as much as necessary so it is visible. If the nozzles all print good, there is no clog in the printhead. As I said before, this test uses only Pico liter ink drops from each nozzle. If there was any clog at all some drops would be missing and you should be able to see them. So again, when you print a photo you are not getting sufficient ink to the printhead to sustain the 3 color ink combination that is trying to produce your picture, so it fades from one color to another. Did you check the rubber pads around the stainless steel ink filters. They need to be clean to make a tight seal. The printhead alignment is also a great idea.

You have every right to be frustrated with your results. If I had a printer that could produce a good quality nozzle check and service test, I would expect that it would also print a great photo. When ever I sell one of my refurbished printers, the last thing I do is a nozzle check, then a service test print, and then I print the highest quality photo I have on the best paper. These all go with the printer to prove it was working fine when it left me.

This is stab in the dark but when I print photos, I disable the ICC profiles, select the Photo Pro paper, and set the quality of print to highest and then set the color/Intensity to Manual. If this is not done, you could be having your photo software generate the ICC profile for the image and when it goes to the print driver, it will create another profile which can really muddy up the picture.

It seems strange you have still not mentioned what kind of ink carts you use, and if you have tried a new set since you have done all the cleanings.

By the way, I just noticed that the Waste Ink level of your printer is up to 46.5%. That is a very high level, which confirms that you have done a lot of cleaning cycles and dumped a lot of ink into the bottom of your printer. Pretty soon you're going to have to take this printer apart and clean those ink pads and get rid of that ink.

 

[turbguy]

I've religiously performed printhead alignments, and I have always used Canon New OEM ink tanks. I change them when the printer says they are low. I will try a new set of carts when I get them (I have a full set of OEM carts on mail order).

I have always printed using Canon's bundled Easy-Photo Print. I have also successfully printed using other software imaging programs (Photoshop, Irfanview, and others). The streaking now apears with output from all software.

As I have said peviously, I just looked REALLY carefully (10x mag glass) at the black bands on the left and right sides of the service nozzle print grid patterns. It appears that these are composed of black short horizontal line segments from individual nozzles. There aren't any nozzles "missing", but it appears that the spacing between some neighboring lines is "off pitch" on an evenly-spaced, repeating pattern, about 1/8", or one paper feed, appart.

It seems to me that if the paper does not advance EXACTLY the correct distance between print head swipes, some portions may be double printed (dark streaks), and some portions may be missed (light streaks). Any comments on this theory?

 

[Trigger 37]

turbguy,... I think your looking at the wrong thing. For what you are searching for you need to use your 10x mag on the color grid matrix patterns that are in the middle. The photos that you print use virtually no black ink at all so they are not involved. Looking at the black bars on the far left and right will tell you nothing about how your pictures print, They are primarly there to show paper alignment. With your 10x mag, look at each of the Cyan, Photo Cyan, Magenta, Photo Magenta and look at each line. So that you understand what you're looking at, each matrix or Grid pattern is made up of short firings of nozzles. The far left vertical line of the grid is all nozzles firing at one time. This makes the vertical line. With no delay, since the printhead is moving from right to left, the top nozzle (and the 10th, 20th,30, etc.) fires for a duration of about 1/32". This makes all the first set of horizontal lines. Then all nozzles fire once again. Then the 2nd nozzle (and the 11th, 21th, 31, etc.) fires for the next 1/32". Thsi makes the second set of horizontal lines. If you look close with the mag you will see the 2nd segment is stepped down by the distance of one nozzle. The grid pattern is continued until each and every nozzle has fired. So if you look close at the grid with the 10x mag, you can verify that each and every nozzle not only fired, it fired at exactly the right time and it was in place. If you can look at all your color grids and verify each line segment is there and not smeared or off line, you will have proved there is no possible clog in the print nozzles. Once other key thing to look at in the grids is the spacing. The vertical spacing is just the distance of the individual nozzles. The horizontal spacing is controlled by the timing strip in the printer. If there is dirt, dust, ink, or anything else on that timing strip, things will print screwy horizontally.

The Service Test Print can tell you just about everything on how your printer is performing. Every line, color bar, and printed text has a specific reason. For example, the very top horizontal line is a test that the paper feed mechanism can register the paper correctly and get it not only square as it feeds the paper, it also gets the line in the exact starting point. The vertical black lines are a test to prove the paper continues to feed straight and the timing strip can return the printhead to the exact position, time after time, at the correct speed, and that the printhead fire exactly at the right time, and that nothing wander out of correct registration. It is actually a thing of beauty for any Service Engieer to see all these test come out perfect. Then you know you have fixed the printer and it is in great condition.