The client is a painter for whom I periodically print scans of a series of watercolors. I've done work for her for a number of years, predating my installation of the 7900. In this case I had to make ten copies of a picture that's 8 x 26 inches (20.3 x 66 cm). Those dimensions include a white border. I make these prints on Epson Enhanced Matte paper. I'd always printed these on a 17 inch wide roll, using a file that puts two copies of the picture together across the width of the roll. I made that file when I had my Canon 17 inch iPF5000 printer, and continued to successfully use it on the 7900.
I wasn't sure I had enough paper left on my 17 inch roll to complete this job. I decided to make a new layout, putting three images across a new 24 inch roll. I opened the file with Photoshop, created a new blank document, and pasted the image into that three times. I placed them to fill the 24 inch width.
With that document ready to print, I cropped the length to 4 inches (10 cm) to make a test strip. The strip had just a small piece from the end of each copy of the painting. My goal was to print the strip and make measurements to insure the pictures were placed and centered properly so when cut apart, each 8-inch reproduction would have the same borders. I wanted all the prints to be identical in every way.
After making the PK to MK swap I set up in the usual way, making a nozzle check print, etc. Invoking the print driver's dialog box I created a custom length for the roll paper, set everything else as needed, and then loaded the roll paper into the printer.
Huh. I then made a series of troubleshooting steps, printing between each. I did the usual and obvious things, including flipping the image 180°, changing the order of images (that is, which image resided on which layer), flattened to a single layer, exited and relaunched Photoshop, rebooted the Mac, and power-cycled the printer. Results varied; these attempts did change things, but I never got the printed test strip to looked like the preview. Below is a photo of a stack of the resulting prints. Top to bottom: not cropped, borderless; cropped; new file; new file, new page size, single, centered image; new file using a 3-up template that's worked fine before; after rebooting computer and printer. The pencil lines are mine, checking positioning.
I had to get this job done, and was tired of wasting time, ink, and paper. I loaded my 17 inch roll, loaded the older two-up print file made for that size roll, and printed. The resulting prints looked fine. I removed the roll, counted the "wraps" of paper around the core, did the math, and determined the roll had enough paper to complete the job, so I did.
In all of this, I did not see the color shift that is the reported bug in Ps CC 2015.5. Perhaps the range of color in the image is within the range minimally affected by the bug. Perhaps I'm just lucky. In any case, a happy client, and happy me because the job is done. But I still can't create a new, multi-print document and successfully print it on roll paper. I've since made single prints on cut sheets and again, not seen the reported color shift. Those prints look very nice (all on Canson Infinity Baryta Photographique sheets). I have not tried printing a single image on roll paper, but I'm awaiting the delivery of files from a pair of clients that will require that, so I'll soon see what happens.
Is this another issue with Photoshop CC 2015.5? Is this operator (my) error? I don't know. I'm considering installing the previous version of Ps and then trying to print the saved 3-up test strip file with all settings made the same. I'd hoped to wait for Adobe to release a fix for the known bug, but several weeks after the buggy release there's still no word on when that'll happen. I may have no choice but to roll back to the older version. Either way I'll post results when there's something to report.
--Jay
17 May 2017: I've posted an update to this.
