Mike Chaney's Tech Corner

Dear all,
I have a little problem and maybe you can help me.
I' printing on my Epson 9880, 3 photos side to side in borderless and they must match exactely at the cut.
The photos sizes in 449mm, when cutting the paper size is perfect at 449mm but it's like if the actual printing is longer.
I can see ink over the cutting point on both side making the photos not matching.
Is there a way to make the printing more accurate?
There is around 1mm of print cutted both side.
In QImage the size is also 449mm, but print a bit more.
Thanks for your help.
Regards
Daniel Bourgade

Hi Daniel,

I'm not sure if this is the metric resolution problem mentioned elsewhere - a few posts earlier http://ddisoftware.com/tech/qimage-studio-edition/feature-request-high-precision-sizingpositioning-in-metric-mode-%280-1mm%29/  If it is, then you may get more accuracy by trying inches instead of mm. (divide 449 by 25.4 and enter the decimals and alter the units to English - under preferences - even though we went metric years ago   :(  )

Best wishes,

Ray

Hi Ray,
Thanks for you fast answer.
I'll check the post and try in inches and I'll let you know.
I hope I'll be able to fix the problem by another way as I'm not familiar with imperial mesearement.
Regards
Daniel

Hi Ray,
I've checked but I'm not sure to have the same problem.
I joint a picture to illustrate my problem.
Thenks
Regards
Daniel

Hi Daniel,

I'm thinking there are a number of work-arounds, none perfect, but maybe get you out of a hole

1) do not use the printer's paper cutter. (It's another consumable to be replaced.) Cut manually. If you are stitching the prints together, overlap and cut the matching edges at the same time.
2) in the printer manual, it will explain how to adjust the cutter position. For you to manually measure the length of flexible paper or canvas to less than 0.25% accuracy is not necessarily simple. For a mechanical device relying on feeding various media through rubber rollers, sometimes dragging it off a heavy roll, it is something else again.
3) print at 448mm length, but cut at 449
4) try printing in some other software. If that is cut OK then possibly use that, it will show there is a problem with qimage, or something odd in your qi settings. If that other software has the same trimming problems, then it looks more likely that your hardware adjustments  are required (or you've messed up this software settings too   ;)).
5) read up on borderless printing and overspray.

Without knowing exactly what you are trying to do e.g. stitching images for a panorama/whatever, and whether it is one offs or dozens or more, it is difficult to give a suggestion to get you to achieve your final objective. Personally, I would never expect the effort of precisely setting the mechanical cutter to be worthwhile - but then I'm not doing masses of batch printing.

Best wishes,

Ray

Hi Daniel,
I see you are printing borderless and from what I can gather, the print width is the same as the paper width (on a roll?).
I'm assuming you have "borderless" set in the driver. If this is the case, the driver will expand the size of the print to ensure complete coverage to the edge of the paper.
You can disable this expansion from Qimage in menu Page Formatting - Borderless Expansion/Overspray.
You must then realise that positioning of the print on the paper relative to the edge is dependant on the printer transport accuracy.

Is Qimage reporting a print resolution greater than 360 or 720 (depending on your driver quality setting)? This number can be seen above the page preview on the main screen and if it is above the the 360 or 720, borderless is set in the driver. The driver may allow you to change the expansion but I'm not sure if it actually allows it to be zero.

Regarding Ray's comments about metric precision, you should have no problem with whole numbers of mm.
The situation with metric precision was improved early on in the life of Qimage Ultimate (where all new enhancements will be made) and sizes can be set to within 0.1mm
Terry

Hi Terry,

If Daniel is using Ultimate, then this thread should be moved to that section. AFAIK, since ultimate was released, the existing bugs, etc. in Studio have not been fixed.

Best wishes,

Ray

Ray,
We don't know which program he's using so hopefully he'll tell us.
The metric thing is strictly not a bug as such, just a limitation with regards to capability.
Anyway, Daniel seemed happy to use ye olde English units if necessary.  ;D
Terry

Doesn't appear metric resolution (1mm versus .1mm) has anything to do with this.  If 449mm is specified as the length, Qimage will print exactly 449mm provided crop is on (scissors button).  You have to be careful when printing borderless that you turn off expansion in the driver when you want exact sizes.  With only a 1mm difference, however, we're talking about two tenths of one percent error and that is much more likely printer/paper slack.  I'd make sure the paper isn't expanding first.  Most shrink a little when ink is applied but I suppose some might expand with full ink coverage.  Measure exactly 449mm on the paper before printing.  Then if the final print aligns with your mark but the mark is now at 450mm, you'll know the paper changed size slightly due to the ink.  If in fact it appears the printer is actually using 450mm of paper, it is very possible that the roller is feeding the paper at a rate .2% too fast.  That's not enough to make streaks (due to ink overlap) so you wouldn't notice.

Bottom line: if you tell Qimage to make a 449mm long print, it will send exactly 449mm to the driver.  What the driver/printer does with it after that is what is affecting the actual length.  Neither Studio nor Ultimate will be off by even a single printer dot and those are spaced .07mm apart even on the lowest 360ppi setting.

Mike