Minimum Print Size

I'm in the middle of a painting repro job. The client has provided two "full sheet" size watercolors, each slightly larger than 30 inches high x 22 inches wide (76.2 x 55.9 cm). The watercolor paper has "deckled" edges, so I'll crop to 30 x 22 and my prints will have clean edges. I've completed the photography, and the color matching and other Photoshop work. I've printed some test strips, which is where this story gets interesting.

First, of course, I had to prepare the printer. Due to travel and some local photography work I'd not used the 7900 for 32 days, a long (for my machine) idle period. Seven channels showed problems on a nozzle check print. I'm fairly sure that's the worst I've ever seen. Two of those channels had only small nits missing, but the remaining five were at least 50% blank. I spent about two hours doing pair cleanings (all of them "powerful") and swapping low-quantity ink cartridges for fuller ones, but finally I had the danged thing cleaned up and ready for use. Just the usual hassle, magnified.

I planned to make a full-width test strip, but I needed only a few inches of the image's height, so I made a custom paper size of 4.5 inches (11.4 cm) high on the 24-inch roll. I set up in the usual way to make that print. Here's a screen shot of the Photoshop print dialog box (double-click to enlarge):

This clearly shows the dimensions, the image to be printed, and its location on the paper. I clicked the Print button, and then the printer produced and cut a perfectly blank 5 inch high piece of paper. This sort of thing has happened before, and it's always a WTF? moment. If you dig around in past postings here you'll find at least a couple of similar occurrences. I've never been satisfied I've found the cause, but in each case I did eventually complete the print job.

This time I decided to dig in to see if I could find any reports of similar problems and perhaps a solution. These kinds of Web searches often turn up plenty of interesting, but tangential pages. That was true of this one, too, but I got no answers to the original question.

"If all else fails, read the instructions" is never bad advice; I did that, and found nothing of use in the U.S. manual (PDFs of the manuals are available via the Web). In the European version of that manual I found this:

"Depending on the paper type, the minimum length of paper you can cut is set from 60 to 127 mm. You can not change it."

That's also less than helpful, but it set me to thinking differently about the problem. I remade my test strip so the print area would be slightly over 8 (20.3 cm) inches high. In setting up the print I made a custom paper size of 9.5 inches (24 cm) on the 24-inch roll, with the rest of the set-up identical to the first (failed) print. This printed perfectly.

That may indicate there is a minimum print size, or at least, a minimum paper size, below which the 7900 will pretend to, but not really print, generating only a blank piece of paper. There's nothing conclusive here because nothing ever is with these machines, and because I changed too many variables (both print and paper size) when doing the experiment. I don't have time to pursue this now, but perhaps next time I need to make similar test strips I'll play with only one variable at a time. If I do, and if I learn anything useful, I'll post it here. Right now I need to get on with making 12 prints for the client.

  --Jay

The Slowest Prints Ever

I got a job a few days ago to make three small prints, these for a local newspaper for whom I've done a few dozen similar jobs. In the newspaper business they have to work fast; their photographers "run and gun," shooting lots of jpegs, mostly with low-end "consumer" DSLRs. The staff cull their photos and go to print quickly; there's no time to process raw files. After some false starts a couple of years ago I've finally trained them (ha!) to set their cameras to make the highest-quality jpegs of which they're capable. This is overkill for what gets printed in the newspaper, but the files now are generally of suitable quality to make nice small prints.

This job was like most others. I made the three files print-ready, set up the 7900 with a sheet of Epson Luster, and sent the first job. Printing started normally, but after a few passes of the printhead it stopped, hunted a bit, and then "parked", as if printing were complete (but had only just begun). Several seconds later the paper advanced a normal distance, the printhead came out, made a pass or two, and then stopped. After a few seconds it made a pass back to the home position, hunted a bit, and then parked. This repeated over and over. Printing did eventually complete, but it took over 20 minutes. For a letter-size sheet! Fortunately the print is perfect.

I started the second print, and the machine behaved exactly the same. This time I grabbed my phone and made a video. This was my first attempt at shooting a video. I have no video editing tools, and really don't have time (or interest) to find and learn any. I hope the video here is at least playable.

 

It shows the printhead moving as a blur, as this is under available light from an overhead fixture out in front of the printer. My apologies for the glare of the printer's front plastic cover, but please understand this wasn't a planned shoot. I just wanted to quickly grab a video to show you this weird behavior. There's sound, but you'll probably have to turn up the volume considerably to hear it.

After the second 20-minute print I cycled power to the 7900. After it booted up I ran the third print. The machine behaved normally, with its usual speed, and the print is fine. I let the printer sleep, and haven't powered it down in many months. Perhaps there's a lesson to be learned.

Update: The day after this happened I printed a pair of panoramas 2-up on 24" roll paper. This was two copies of the same image, 36 inches long x 10 inches high (91 x 25 cm). I did my usual setup, first waking the machine from standby and then printing a nozzle check, which found problems with LLK. A standard cleaning of the Y/LLK pair resolved that. The printer once again exhibited the behavior described above. I canceled the job after a couple of minutes, cycled power to the printer, resent the job, and it printed normally.

Today I made another single, small print for the newspaper client. Again, the usual setup, waking the 7900 by inserting a sheet of bond paper and then running a nozzle check. No problems found. I then printed the single letter-size sheet of luster. The printer behaved normally.

  --Jay

Ink Cartridge Error

I've spent much of late spring and early summer preparing for the three-day outdoor "Arts in the Park" show organized by the Hockaday Museum of Art, in Kalispell, Montana. The show would run July 15, 16, and 17. I'd not exhibited in an outdoor show since 2014. I have a lot of work that's new since then; to prepare I needed to make a number of prints in an array of sizes. This included prints for frames, and also for the 'matted and bagged' pictures that are popular with summer visitors.

It's a juried show and competition is tough, so I was quite happy back in May to receive the acceptance email. That's when the work started.

I determined early on which images I'd display, and the sizes of prints needed. The 7900 performed very well. As is often the case when printing daily or nearly so, I experienced very few nozzle issues. Run these things a lot in the conditions they prefer, and they'll behave nicely.

We did well at the show, and while there I was talked into exhibiting in another show, this one running two days, at the end of the month. To prepare for that I need only print replacements for some of the pictures sold at the Hockaday show, plus a couple more that weren't shown there. I made the first of these prints two days ago, and once again had no problems with the printer. I wasn't so lucky yesterday.

When setting up to print, a nozzle check showed some missing nozzles in PK. This is paired with LK, and my LK was at 1%, so I swapped in a new LK and ran a cleaning cycle on that pair. When I tried to print a nozzle check after the cleaning, the printer's LCD showed this:

VLM is installed, and should have about 20% remaining.

A few days prior to this I'd noted the ink levels in each cartridge, and VLM should have had something over 20% remaining. Nothing I'd done, as described above, touched the VLM cartridge. I opened the right cartridge door, removed the VLM, gave it a shake, reinstalled, and after the inks pressurized checked the LCD. It showed the normal VLM, so I tried again to print a nozzle check. This failed to print and the LCD again showed the "NO CARTRIDGE" message for VLM.

Again I removed the cartridge, and this time I lightly rubbed an ArtGum (tm) eraser on the cart's chip contacts. I reinstalled the cartridge, and have been printing without issue since.

Just for fun I had a "chat" with an Epson support person via their Web site. He suggested this: "Ok, please try pressing the Pause button like 4 or 5 times some what fast then see if the printer goes to a ready state." Of course, by then I'd already used the eraser and the printer was working, so I don't know if following his instructions would have made a difference. In the end he suggested I call their "Professional Printer" support line because they may want to replace the VLM cartridge.

I made the call, explained everything from the start, and was told to buy a new VLM, install it, and see if the problem returns. If it does, it indicates a sensor fault in the printer. If it does not, it points to a failed ink cartridge, which Epson will replace.

Since I need to do a bit more printing for the next show I did order a VLM, which will be here tomorrow. In the meantime I've made more prints and experienced no problems.

  --Jay

A Long Overdue Update; Roll Printing Failure

In July, 2016, I posted here about a problem I had printing multiple images across the width of a roll. My computer (Macintosh) and OS (10.11.6, "El Capitan") have not changed, although I have installed several security and other updates from Apple. Epson's OS X driver and the 7900's firmware have received no updates, but both are the current versions. However, the problem occurred with Photoshop CC 2015.5. I've got the now-current version 2017.1.0, and I can report success printing 2-up across a 24-inch roll.

Yesterday I wrapped up a job making 48 prints, each 10 inches by 15 inches (25.4 x 38.1 cm). I printed these 2-across, with the printer cutting the paper after each pair of images. This resulted in a sheet 24 inches wide by a little over 17 inches high. I then cut each into 11 x 17 inch sheets with the picture centered (I use a Dahle 444 cutter, which I'd describe as "the right tool for the job").

When setting up to print, I sized and optimized each image file, and then pasted a pair into a new Photoshop document 24 inches wide by 17 inches high. I put guides in the appropriate places, pasted each of the two images into a new layer, cropped to the edges of the image pair, and then printed on a custom paper size (17 inches on 24-inch roll, centered, with standard margins).

The 7900 printing a client photo 2-across on 24-inch roll paper

This worked exactly as I expected. No errors, no truncated prints. Whatever was happening back in July seems to be resolved. I can't know with certainty since I never did further testing with the older version of Photoshop, but it seems a fix was made in some version after 2015.5.

In any case, I'm happy, and the client's happy.

  --Jay

Exercising the Printhead During Slow Periods

Problem: Nozzle clogs.

Solution: Greeting cards.

For an explanation, see the February, 2017 article on my Web site.

  --Jay

39 Days

I've not made a print in some time. I've done little photographing lately, and it's a slow time for client jobs. Here is western Montana we're in the middle of what is, so far, the third-coldest winter on record (more about our recent weather, and some photos, in my latest article). We've also had lots of snow, on par, I think, with the snowiest winter I've seen in my fourteen winters here. That's not a complaint, as I love the snow and getting outside in winter. It's just that I've not been doing much of that this year.

Two days ago I wanted to make a couple of small prints. I had MK loaded from the last client job I'd done back in December. Because the 7900 had been idle for some time, I knew it would punish me, as they do, for that lack of use. And it did: the first nozzle check showed about half of LLK missing, and a couple of blank spots in VLM. The LLK cartridge is fairly new, while VLM has been at 1% for a long time; I temporarily installed a new VLM. Rather than try to clear these I did a MK to PK swap, which does an auto-clean. When the swap finished I made another nozzle check print. This showed ALL of LLK missing, a large section of VLM missing, and a couple of blank nits in PK.

I then performed a powerful cleaning of the Y/LLK pair. With Y at 2%, I replaced that, temporarily, with a new Y cartridge.  When the cleaning finished LLK was perfect, but PK and VLM had not improved.

Finally, I did a powerful cleaning of the C/VLM pair. After that cleaning there was a long delay, and then the printer did an auto-clean (this is displayed on the LCD). When finished, a nozzle check showed a tiny gap in LC (which had been perfect before), and several small gaps in VLM, in different locations than the larger blank area after the previous cleaning.

I don't know how much ink all of this consumed, but the waste cartridge went from 20% after the first nozzle check, to 14% after the last one.

At this point I just wanted to get on with the job, stop wasting time and ink. I set up to make my prints, which would be two copies of the same photo, on letter-size sheets. I sent the job, and the printer did its "calibration thing", in which is moves the head verrrrry slooooowly the full length of the carriage, and back, a number of times. I didn't count, but I'd guess it made half a dozen passes. Then the LCD flashed "Auto Nozzle-Check" for half a second, and finally it printed. The print, and the second copy, looked fine.

I write the date, the relative humidity, and the room temperature on every nozzle check print. Looking at the last one I did back in December, I found it had been 39 days since I'd last printed. That is, by far, the longest idle period my 7900 has ever had in the five-plus years I've owned it. Also, because it's been so cold this winter, the room heat is running more than has been typical in recent winters. As a result, humidity in the print studio has been quite low, typically under 35%.

Today I set up to make two more small prints, same format as before, different photos. The first nozzle check, and the two prints, are perfect. Two days ago, getting this job done took most of an hour. Today it took no more than ten minutes.

  --Jay