Mike Chaney's Tech Corner

Due to the fact that some roll stock (e.g. thick fine art paper) will slowly "drift" left or right, I tend to center my prints so I get consistent margin widths. Therefore, it would be great to have a mode of Intellicut that packs the images for optimum cutting, but also centers the images so that if there is any waste, it is equally distributed around the outside.

Thanks.

Cheers!

Brad

Let me add that centering "across" the roll (left-right) is the real requirement. There is no "drift" in the other direction as this is the direction the feed rollers operate.

Have you tried intelliCUT  mode?
Fred

Yes, I have. I am proposing an enhancement to Intellicut.

By default, IC mode doesn't solve the situation that I encounter with certain roll papers that slowly drift sideways as you print through the roll. A prime example is Breathing Color Elegance Velvet which is a thick fine art paper. After a few prints into the roll, the left margin will have moved. Knowing this happens, I set up those prints in Ctr mode. That way, if the roll drifts left or right, I won't lose any image when I trim off the left and right edges.

However, Ctr mode doesn't bring the images together in the middle of the media so as to optimize the cut lines . Hence, the suggestion of a Ic mode with Ctr option.

Cheers!

Brad

I have no experience of large roll feed printers but my first reaction to your request is - sort out the source of the problem.
Why is the roll drifting; is there a problem with the printer and its mechanical set-up, is it old and worn?
I've not seen any other users of large format printers mention this problem on the forum.
Terry

Brad,
Reading Terry's engineering thoughts, caused me to call a friend who is a prominent professional photog and who prints all the time on a very large format printer on roll paper.
I asked if he ever ran into such a problem as you described.
He answered very simply that he had and others too, but the solution was to make sure the end caps on the spindle / spool were on tight so the roll cannot slide side to side at all on the spool.
Could this be the solution for you?
Fred (and Terry)

I would go for Fred's solution first: try to correct the problem at the source.  But even if that's not possible, there is a solution that is better than centering across the roll.  Failing correcting the feed issue, if you know the paper might drift as much as 1/4 inch (as an example), just add 1/4 inch border on the left and right.  Go to the page margins and add .25 in the "additional" margin on the left and right.  That's the only way you can ensure that the left and right 1/4 inch of the roll is not printed upon.

Roll drift would only be a problem if you are printing with no margins: where for example, you try to print 44 inches width on a 44 inch wide roll.  Then you have no leeway on the sides.  When doing that, even IF you centered prints on the roll, you can still run into the situation where you have two 22 inch wide prints across the page... or four 11 inch wide prints: basically any combination that adds to 44 inches wide.  In that instance, it'll still allow you to print that, but centering the prints will result in nothing happening because they are already centered as there is no "slack".

So the solution is go add a 1/4 inch, 1/8 inch, or whatever margin is needed so that your printable area is now 43.5 inches or 43.75 inches.  That margin will ensure that the left and right 1/4 inch, 1/8 inch, or whatever slack you choose is never printed.

Mike

Thanks guys.

First, thanks to Fred for confirming the issue is real, but perhaps under-reported. This paper "creep" issue happens only on the thicker textured papers which are perhaps not popular with photographers, but certainly are with my art reproduction clients. It's not a problem for small jobs (1 or 2 prints). But I frequently enough get clients who want 10 or 15 copies of an image and then the paper "creep" can become noticeable.

Of course, I do ensure that the spindle hubs are pressed in tightly when loading the roll, etc. That by itself won't fix the problem. In fact, some roll stock (looking at you Hahnemuhle) has a diameter, when the roll is new, that is actually larger than the spindle hub, allowing the first dozen turns of paper to "creep" over the hub after enough prints. I suspect the problem is due to the thickness of the paper and tiny variations in density, or something. The spindle and spindle hubs only control the paper at one point in the paper path, which is about a foot back of where the rollers are pulling the paper through. The "creep" occurs at the rollers.

Mike, I'll try the margin adjustment trick and see if that helps. Thanks.

Cheers!

Brad