Canon ipf 8400 soft verticle banding

[seesee]

Canon ipf 8400 creating a soft semi diagonal banding in dark mid tones ONLY when using the photo black (right head). Printer is calibrated, fine head adjustment done, nozzles check perfect. Printer settings are at maximum quality for prints. Problem started in the middle of a large print project while in use. Canon Technical support denies ever seeing this problem. The bands run perpendicular to the direction of head travel. Any one else figure this out or experience the problem? I have attached an example picture. Again the banding is perpendicular to the direction of head travel. Thanks.

 

[DYP]

Does it happen on all media?

First thought it is a media coating problem.

 

[benstarr]

My thinking is it would have something to do with the encoder strip or how it's being read, I don't know enough about that model to really know what to do to resolve it but maybe that's something to start looking at.

 

[seesee]

Thank You for your reply. It occurs on multiple media if I use the Photo Black Ink. I called Canon yet again and finally a tech acknowledged they have seen this problem and that it is the head position sensor. I was instructed to clean the encoder strip and try again. IO did its clean still have the problem.

 

[seesee]

benstarr - Good call! I called Canon yet again and finally a tech acknowledged they have seen this problem and that it is the head position sensor. I was instructed to clean the silver and clear strip inside at rear of printer which positions the head accurately and try again. I did, its clean was not dirty and still have the problem. I assume that the encoder strip is what I cleaned. It only occurs with the photo black ink and the prints using matte black are still,excellent quality.