This article is more than 1 year old
BOFH: Sure, I could make your cheapo printer perform miracles
Just as sure as a cattle prod goes BZZZZZT!!!
Episode 4 It's yet another one of those Fridays where ALL I NEED TO DO IS MAKE IT TO 4pm..
And in the red corner there's a senior beancounter who thinks that HIS problem with the 30 quid inkjet printer that he brought in from home is somehow MY problem...
"So it's still not working?" I ask.
"It's WORKING," he replies, "but the colour just isn't right. It should be slightly bluer. Maybe a little more yellow as well."
"So you mean greener?" "No, blue and yellow."
"No, I need Blue in one area and more Yellow in another."
"Have you tried increasing the saturation of the image?" I suggest.
"No, the printer should print it the way it's supposed to be printed. I don't want to go and change the original!"
"You could make a copy?"
"Have you tried using the office production colour printer?" I say, knowing full well that the simplest solution is often the most unappealing...
"It's on the other side of the office and I can't keep on traipsing back and forth to the printer every time I need a true colour copy."
"Oh, so you've got a problem with several images?"
"That's not the point! The printer should print the right colours."
Years ago I ceased being surprised at how much effort people will put into being lazy – or to be more precise – how much effort people will put into avoiding doing something themselves.
"Oh, gotcha! So you just want an accurate representation of the colours on the original image out of that old, cheap and unsupported USB inkjet?"
"Sure, I think we can help you. First we'll need you to power-cycle the printer so that it does the selftest, clears the jets and runs through it's positional calibration system."
"Ok. So I'll turn it off >click< and then I'll turn it back on again >clack<"
"Uh no, you need to switch it off, wait five minutes, THEN switch it back on. You do that now, and then call me back when you're done.."
..two minutes later..
"Okay, so the printer's done its reset."
"It can't have. It's not been off for five minutes!"
"There's hardly a difference between two and five minutes!"
"Of course there is!" I blurt. "Inkjet printers use atomised particles of ink sprayed at a point in the page. If you don't wait five minutes then all the particles of ink are still granulised in the reservoir - so it doesn't print colour correctly. You need to let all the particles return to the correct fluid suspension so that the additive combinatory matrix is correct."
***DUMMY MODE ON***
"The what now?"
"The additive combinatory matrix - the way colours mix together to get the colour you want."
***DUMMY MODE OFF***
"So you just switch her off, wait five minutes, then switch her back on, then let me know if it's sorted."
Obviously it's not going to be sorted as it's a crappy four-cartridge inkjet which has problems even printing black correctly. The only reason we're having this conversation is because he's trying to force me to say the printer is knackered. If I do he'll tell his boss he needs to replace the inkjet with a four-colour production quality unit directly attached to his desktop so that no one will ever (again) see the second half of the LOVINGMOUTHFULLXXX series of JPEGs come spewing out of the printer on Monday morning when someone refills the A3 glossy paper tray...
"Okay, it's back on but the problem's still there."
"It's not been five minutes!" I say
"YES IT HAS!" "Yes, it's been five minutes since you called, but not five minutes since you switched it off!"
"No, I'm looking at the USB monitor on your machine. It showed a USB disconnect and then a USB reconnect three minutes, 38 seconds later."
"It must be wrong," he lies.
"Well how about you try it for seven minutes and that way if your USB monitor has some clock issue at least we know it was five. Call me when it's done."
There is no USB monitor and there never was - I just know he wouldn't do five minutes unless he was forced to. That, and I need to keep him testing things for another 35 minutes before I can slip out to the pub.
"Still the wrong colour," he says.
"Okay, so that's the atomisation issue checked off. In that case it's might be the heat from the stepper motor. Switch it off for 10 minutes - no less - and then switch it back on."
"How can it be heat?!"
"Different colours respond to different heat profiles. So exposing an ink to 40 degrees Celsius for two minutes isn't the same as exposing it to 80 degrees Celsius for 1 minute. What we're trying to do is see if the heat from the stepper motor in the printer is causing a colour change."
"But wouldn't I just change cartridges and do a print as soon as possible before the new ones warmed up?"
"That would only work if it were a permanent colour change and not a transient one from the jet stream coming into contact with a heat point source. No, what we're trying to do is isolate the issue of a heat point source affecting the atomised stream of chromatic ink particles and causing a register shift."
***DUMMY MODE ON***
"The heat coming out of the printer changes the colour between the jet and the page."
*** DUMMY MODE OFF ***
Eight minutes later...
"Okay, so I've powered it down for 10 min.."
"No, it was only 7 minutes 30," I say.
10 minutes, 23 second later..
"Okay I've switched it on and it's still printing the wrong colour."
"Did you still have the colour calibration card?"
"What colour calibration card?"
"The one that came with the printer," I lie, knowing full well that everything that came with the printer would have been binned years ago. "It will have the words DO NOT DISCARD printed at the top."
"Ok, well do you have a metal pen with ink of standard blue?"
"My Mont Blanc?"
">Sigh< We're trying to find a quality pen with a standardised colour which hasn't been exposed to extremes of heat that would have resulted in an asymmetric chromatic shift. Plastic pens don't have the heat-conductive characteristics that would result in a symmetric colour shift, so they'd have a graduated change."
*** DUMMY MODE ON ***
"Metal pens get warm all over whereas plastic ones get warm in one place. If there's been a colour change we need it to be standard over the cartridge."
*** DUMMY MODE OFF***
"So whip the refill out because we need to expose it to a tiny amount of heat at the tip."
"Because we're going to get the tip of it warm so that we can compare the colour shift in terms of chromatic gradient over a standardised test pattern which should exhibit the same predictable colour shift as the pre-jet ink reservoir.
*** DUMMY MODE ON***
"Uh huh. Now what?"
"I need you to slide that pen into a calibrated heat source. Do you have a calibrated heat source in your office?"
"Okay, we'll just use the power supply of your PC..."
. . .
It's 3:59 and I'm in the pub just as the ambulance pulls up.