Canon i960 Magenta problem?

[mmconhea]

Thanks for the tip. I'll leave it alone.

 

[mvalentiner]

My i960 developed this problem the other day after working fine for years. After changing inks, cleaning heads, and deep cleaning heads it still has the problem, but only when I print on Photo paper (Canon Matte Photo or Glossy Photo). It prints fine to plain paper. If I print a test page on Photo paper, PM is blank and square E is almost blank. If I print to plain paper PM shows up fine. Anyone know what gives?

 

[mvalentiner]

I deciced the problem I was seeing was due to a clogged print head, so I stayed up half the night cleaning it. I was able to get the printer back to a resonable degree of functionality. Along the way, I realized that any printer is an imperfect physical device and I needed some way to evaluate whether the print head is "clean enough". So, I made a test image in PS, 8.5 x 11 @ 300 dpi, consisting of alternating black and white pixels. That is, not a gray fill, but a 4 x 4 pattern fill where two pixels on the diagonal are black and the other two white. This resulted in a 2550 x 3300 checker board.

What do you think that should look like when printed? Ideally, I thought, it would be a nice smooth 50% (or there abouts) gray. NOT! The first printing was full of lines, streaks, moire (of numerous types), color banding, ghosting, etc. It looked horrible (it was printing plaid - nothing against the Scots). Eventually, through a variety of cleaning techniques (documented in various threads at this web site), I able to get the page to come out an improved smoother gray. Still there is plenty of banding, moire, color ghosting, etc., but it is improved and acceptable for a non-color-critical-just-messing-around-at-home photo printer. None of this is really noticeable in most images, unless they have large areas of smooth color.

The cleaning technique that yeilded the biggest improvment was running a few drops of isopropyl alcohol throught the printer head, letting it sit, followed by a deep cleaning cycle, and printing my evaluation image through a few times.