Epson 9900 - prints are longer than specified

[Stephen G]

I'm struggling to figure this one out. I thought I'd seen all this printer's tricks.

I'm sending prints sized at exactly 600x420mm to my 9900. They are coming out 603x420mm, so it's about a 0.5% increase in length.
Media settings are correct for the paper: defaults for Epson Hot Press Bright
I get the same result from QImage Ultimate or Lightroom.

If I run 120mm length test prints on various roll media, with default settings, I get:
Epson Enhanced Matte 17" roll: 120mm - no measurable error
Epson Hot Press Natural 17": 120.2mm maybe 120.3mm - tiny error, hard to measure accurately with my metal rule, but it's visibly different to the Enhanced Matte result.
Epson Hot Press Natural 24": same as 17"
Epson Hot Press Bright 17": 120.5mm, so a similar error to the 600mm prints above.
Epson Cold Press Natural 24": 120mm - no measurable error

Epson Enhanced Matte settings (changed thickness to 0.3mm) on Hot Press Bright: 120mm - no measurable error

So it seems that I've got an issue with the Hot Press papers. Has anyone else seen this and, perhaps, know what can be done about it?

[mikev1]

Hmm, that's an interesting problem.  You see this all the time with canvas due to stretching but I haven't experienced this with other media.  Possibly some slippage as it is moving through the printer?  Maybe increase the suction?

[Landscapes]

I really don't think the problem is stretching with canvas.  It does happen with canvas, but my hunch is that its because the printer finds it more difficult to perhaps count how much it is advancing.  The fact that this happens again on these textured papers doesn't surprise me because its just a more mild form of texture as on the canvas.  Its kind of like the optical mouse.  It doesn't work on glass since it can't see how far its being moved.  You can get it to work on your sofa, but here, the pointer sometimes jumps a bit as well as the optical sensor seems to be fooled with how far the mouse traveled.  I imagine its the same mechanism with figuring out how much paper/canvas has been advanced for each pass.

[Stephen G]

This is like the canvas problem, in a way, except I'm getting prints that are too long instead of too short. I get the prints-too-short problem with Hahnemuhle German Etching paper - not much, it only needs a 0.2% compensation, but a customer who prints long images noticed that my sizes were inaccurate.

The main source of irritation for me is that I've been using Hot Press natural regularly for 4 years and I've never noticed this before. Have ALL my Hot Press prints been too long? grrr. After doing a few measurements years ago I've always just trusted the default settings for a given paper to get it right.

Can't increase the suction, the driver only gives options to decrease it.

I'm beginning to suspect that it's a very localized problem. Just my printer, 'cos it's over 4 years old and maybe the feeding rollers and motors are 'misbehaving'. And only in the past week or so. We've been having a spell of very dry weather and all my paper is acting very curly and strange. I'm going to test things again during the predicted rain next week and see if it's any different.

[Stephen G]

Cracked it! It's ABW mode that makes the printer print too long on the Hot Press papers.

All my previous tests were done in ABW mode. The original 600mm image that was coming out 603mm is BW so that's the mode I was using to print it, and that's the mode I ended up doing my tests in. I changed the driver back to colour and the print length is correct.

It would be valuable if others could test this so we know if it's just my setup that's doing this, or if it's universal. I'm on Win 7 64 bit, driver version 6.73, firmware HW129C5,2.11,A000

I'll have to dial in a Paper Feed Adjustment to compensate when I'm using ABW from now one - hope it doesn't introduce banding.