UPDATED 7/25/2009 in yellow below.

The Epson 7900 is a fabulous printer from both a mechanical/ease of use perspective as well as a print quality perspective.  The new roll feed system is outstanding, the rugged engineering seems stellar, and menus and interface both on the printer as well as from the driver of OS X are simple and easy.  The print quality is fantastic ... better than I originally thought, especially if you have very high quality files.  Unfortunately it isn’t without issues.

BUY AN extra LK INK CARTRIDGE ASAP !

The LK ink in the 7900 will need replaced very quickly. Buy one when you buy the printer, or shortly there after. Once you do the initial ink fill you will have about 60% left in all of the colors ... except for LK.  It will only have about 38% left.  When you run out of LK ink, you will probably have about 40% left in the other colors, depending on how often you need to do nozzle cleans. If you are going to run the 350ml cartridges in your printer, I would recommend using the 700ml LK cartridge. There are three reasons the LK needs replaced so quickly.

Two are due to LK ink sharing the channel with the PK/MK inks.  The printer provides one of these two inks and LK ink to a channel in the head.  This consumes extra LK ink in two ways. First is in the initial fill.  The printer will load that channel with ink, pushing the MK and LK inks through the lines to the head.  After the MK is loaded, it will switch and pull the PK ... and you guessed it ... more LK ink through the line.  Too bad Epson can’t design the start up process so you don’t insert the LK ink until it has pulled the MK ink (and air in the LK line) into the printer, then when it’s ready to initialize the PK ink you then insert the LK ink.  Maybe it wouldn’t work, all I know is when you are ready to start printing you will have dumped about 25ml of LK  ink into the waste tank (which by the way will already be at 70%).

This also means whenever you change from PK to MK or back you will also lose some LK ink as well. I don’t use MK ink much at all, so I haven’t made the switch to see how much LK you might lose when you do this.

There is another and very acceptable reason the LK goes down much faster.  Checking the job sheets, the printer uses LK ink more than any other color ... substantially more. On many jobs it took as much LK ink as all of the other colors combined - these are full color images, not black and white.  I would guess the screening process utilizes LK to lower saturation. Whatever the reason, this is why I recommend using the 700ml size if you are using the 350ml cartridges for normal operation in your printer. I have no problem with LK ink being used faster than other colors ... makes perfect sense.  I don’t mind ink that goes onto the paper ... I just hate dumping it into the waste tank.

CAN YOU SAY CLOG!

Speaking of ink going into the waste tank, with this printer there seems to be a lot more of it getting dumped into the waste tank than there should be.  Despite the many outstanding features and output quality of this printer it does seem to have an Achilles' heel affecting quite a few users.   Clogging nozzles in pigment based inkjet printers is a fact of life.  Unlike Canon’s and HP’s where these clogs are effectively hidden from the user, with an Epson you are usually pretty aware of any clogs.  Over the past few models Epson has made great improvements in their printers to lessen nozzle clog issues, and the technology offered in the new 79/9900 printers was supposed to make this even better.  With Auto Nozzle Checking to detect clogs and clear them automatically, as well as several new head improvements to reduce clogging, the experience should be very satisfying - in fact much like the competitor’s models with this printer clogging should be virtually invisible to the user.  Unfortunately for many it isn’t working out that way.

A great many users report excessive ink consumption with these printers.  Most believe it relates to the ANC (Auto Nozzle Check) function, and think if they “turn it off” it is disabled and things are good again.  It isn’t quite that easy however.

I estimate my first 7900 consumed anywhere from 1,000 to 2,000 ml of ink clearing “clogs”.  It was a learning experience, and to Epson’s credit they were very responsive and aggressive trying to address and fix the problems including enough replacement ink to more than make up for the waste.  At least 50% of the time when starting the printer I would have massive amounts of missing nozzles.  Despite ANC being “disabled”, cleaning the printer would almost always result in multiple cleanings.  I was only able to print about 10 to 15 prints before having to replace most of the inks, and not long afterwards I had to replace my maintenance tank.

I know others have reported their 79/9900’s are fine, but after a couple of phone calls I’ve found that some believe just disabling ANC resolves the problem (and in fact that will help sometimes).  I ask them how often they have to actually perform a clean when they start up the printer and most say 1 or 2 times a week.  Isn’t that “normal” for Epsons?

NO.  Absolutely not.  I have an 11880 printer that is over 1.5 years old that has only required cleaning a handful of times.  I have started up this printer and run a nozzle check HUNDREDS of times without a problem.  My current 7900 (the replacement for the original one) requires a cleaning over 50% of the time.

It appears after breaking in two of these printers (Epson replaced my original 7900 because they couldn’t seem to resolve the problems) there seems to be two issues going on with some of them.  The relative challenges each user has will depend on whether their printer suffers from either or perhaps both of the problems.

The first problem is Auto Nozzle Check.  While great in theory it doesn’t seem to deliver reliable functionality.  Almost every user I know has “disabled” the function in the menu (which doesn’t really disable it, more on that coming).  Symptoms of ANC not working are two fold.  First if you have ANC enabled you will find the printer “cleaning” at odd times before making a print.  If you have ANC set to check before each print you are more likely to see this problem.  The second symptom is the printer cleaning multiple times when it does need a nozzle clean, often followed by an error message that cleaning failed and asking if you want to clean it again.  You should answer no to this and verify the printer does have missing nozzles with a printed nozzle check.  Most likely you will find the printer is fine, the nozzle check circuitry just isn’t working right and is erroneously reporting a problem.

The second problem is excessive failed nozzles.   The main symptom is when powering up the printer and printing a nozzle pattern the printer will have missing nozzles ... some times massive numbers.  They may affect one color or many, but when a color is affected it often it is a large number of nozzles ... 30-70% of them.  I’ve never had this massive of nozzle failures in any Epson printer, except perhaps the 9600 that sat in  the basement for over 2 years without being turned on.   Obviously this means the printer needs to  be “cleaned” far more than it should, again dumping ink into the waste tank.  On the first 7900 I had, I consumed all of the original waste tank and 50% of a second.  A lot of ink.

I hope Epson is aware of the problems and will come up with a way to resolve it.  The ANC function should work as advertised.  After all it is a highlighted feature of the printer and one of the reasons these Epson printers were the next generation in reducing clogs.  In addition, whatever is causing the massive amounts of failed nozzles when printer is powered off or sits idle for a day or so should be resolved.  This is the worst Epson I have ever owned as far as clogging issues, and I’ve owned nearly every model they’ve made.

In the meantime I do have some advice to keep things manageable.  You can take control of the cleaning process manually and if your ANC is causing problems with unnecessary cleanings you can manage to bypass it completely.

First disable ANC in the menu.  All this does is prevent the printer from doing a nozzle check before printing a print (a great feature if it worked).  What it doesn’t do is prevent the printer from doing an ANC anytime you actually start a manual cleaning process.  So if the printer has a clog and you go into the maintenance  menu to initiate a clean, when the cleaning is finished, the printer will do an Auto Nozzle Check.  If the ANC circuitry is defective it may indicate a clog when none exists and initiate more cleaning cycles, perhaps to the point where you get the error message that cleaning failed.

To get around this, don’t initiate a clean while in the standard mode.  Instead when needing to clean nozzles, startup the printer in service mode, which allows you to initiate several different levels of cleans.  In service mode, the printer does not do an auto nozzle check when cleaning, which means you can completely control the cleaning process manually without fear of the printer cleaning itself unnecessarily.  As an example, if you have colors in just 2 different channels clogged you can’t use the channel clean function in standard mode to clean them one at a time.  If you clean one channel, the ANC will report clogs and the printer will go ahead and clean itself until it the ANC reports no problems.  In service mode you can clean individual channels or the entire head, and you can perform 4 different levels of cleans (CL1 to CL4, CL1 being the least aggressive).  It seems to me CL1 uses a little less ink than the standard mode cleans, taking about 1-1.5ml of ink per color, and I have never needed more than CL1 to completely resolve all nozzle problems when I have them.

To get into service mode, hold down the center(menu) button, the down (paper advance) button, and the right (menu) button simultaneously while powering the printer on.  Once the printer is on, you can verify you are in service mode by hitting the menu button ... you’ll see a much different menu than you are used to.

WARNING: Use service mode at your own risk.  Don’t do anything else while you are in service mode.  There are calibration and adjustment routines that are performed by technicians, and if you start them you may create problems (which Epson may not fix under warranty).  I’m not particularly worried since it is pretty straight forward once there ... just select the cleaning menu and stay away from the other choices.

Finally, some users report that the printer seems to “break in” and settle down after a period of time.  This second printer seems to be following that trend ... this week for example I have had only 1 color clogged (about 30% of the yellow), and doing a single channel clean resolved it.  I’ve printed quite a bit this week with no other issues, and I have been running with ANC on for every print now for a couple of weeks without fault.  So at this point the printer is getting somewhat close to what I would expect.

(UPDATE:  I’m happy to report that after about 3 weeks, this 2nd 7900 stabilized quite nicely.  It’s now been nearly 1 month since I had a clog.  Even a 2 week hiatus without turning the printer on revealed no clogs when I finally started it up again.)

DON’T REPLACE THAT INK CARTRIDGE TOO QUICKLY!

The printer will start giving you a warning about ink running low when there is about 10% left in the cartridge.  On the first printer I went ahead and replaced the cartridges when they got down to 2 or 3 %, but I no longer do this.  The printer itself will stop when it runs out of an ink and ask you to install a new cartridge.  It will do this in the middle of the print and doing so will not cause an artifact in the print.  This is a stated feature of this printer, and I’ve done it a few times now without problems.

Why should you do this?  Well, I’m currently at 1% of LK ink in this second 7900.  I have printed 20 to 30 square feet of media since I hit the 1% mark.  Since this is a 110ml cartridge, 1% is only about 1ml of ink, yet since I hit the 1% indicator in the printer I have printed jobs that consumed over 10ml of ink.  This means when the printer was reporting only 1% remaining, I probably still had over 10% of the ink remaining in the cartridge.  Easy fix ... just wait until the printer stops and waits for you to replace the empty ink cartridge.