A week ago I got a job to print ten 8x12 inch and one 16x24 inch black and white photos for a local portrait photographer. She's putting together a display for marketing purposes; she chose a range of subjects, all photographed in the same outdoor location, the doorway of an old barn on her farm.
I made a couple of prints a day, on a 24-inch roll of Epson Luster. The machine started each day without issue, a perfect nozzle check, and then I made the prints. As I've said here many times, the 7900 can be a joy to use when things work well, and the week's work only proves the point; using the machine frequently and regularly keeps everyone happy.
I finished the job by making the large print. I started with a nozzle check, as usual; it was fine, so I fed the roll paper, and started the print job. Several inches into the print the 7900 stopped, displaying a message that LK must be replaced. It's been well publicized that these machines can stop mid-job, ink can be replaced, and then the printer will continue with no visible evidence an ink change had been done. I know this to be true from my own experience. But I'd never had to do it in the middle of a black and white print.
When the message appeared, I removed the empty LK, replacing it with one that had been used for several cleanings. It had 92% of its ink remaining. Swapping the ink took no more than 90 seconds. I closed the ink cartridge door, the system pressurized, and printing resumed. Cool.
The print finished and was cut from the roll. I placed the print on my work table and immediately saw a dark band in the black background. Below is a photo of a part of the affected area. You can't miss the flaw through the horizontal center of this snippet. This is, of course, exactly where printing stopped so the LK could be replaced.
I let the print dry 24 hours, but found no improvement. Interestingly, the dark band is obvious under florescent lighting, but almost impossible to find in today's cloud-softened daylight. In any case, the print is scrap. I made another a few minutes ago. A normal print, no messages from the 7900, no need to swap inks.
Although my sample size is only one, I'll take this as a lesson that when printing black and white, perhaps especially those with large, very black areas, it is NOT cool when printing stops for ink cartridge replacement. I suspect the same would be true for any color image that has large, solidly-colored areas. Should this happen again I'll cancel the job so as to not waste any more paper and ink than necessary, replace the empty cartridge, and start the job over.
--Jay
