? Roller marks running vertically down Digital Negatives

Hi Folks,

I’m getting good at solving printing dig negatives, but I can’t figure this one out. I have an Epson 3800 printer. I feed Pictorico through the rear feed with the front tray up and a “q-tip” stuck in the left side so that I don’t get Pizza Wheel marks.

I only print when I can get a good nozzle check and I’m getting good at feeding paper (a little away from right edge of feed slot) , and at preventing head strikes.

Here’s the problem:
I am getting what I figure a roller mark would look like 2.25 inches in from the Right edge of the Pictorico. It is 3/8 inches wide and goes the full length of the image, though I don’t see it in the black borders at the leading and final edge of the print. It prints out on my cyanotypes as two parallel lines with the area between the edges the same density as the rest of the image. The problem is more noticeable in mid-tone/light images and obscured in complex very dark images.

The problem mark does not align with any rollers I can see through the front opening. It seems to be on the printed side of the Pictorico.

The marks do not occur if I run a sheet of paper through (instead of pictorico) while keeping everything else the same.

I’d appreciate any suggestions on how to get this mark to go away. My alternative is to just make dark, moody prints, but I making a serious effort to lighten up a bit!



do this. Set you platen gap on the printer to something like “Wide” and then back your film to a piece of fiber fine art inkjet paper to simulate a “thick” piece of film. Run the same neg again. If you don’t have the marks then you know it’s something with the head height vs neg thickness. If the it is still there than something else is going on.


OK, I can do that. Thanks.

I set platen gap to “widest” and ran a test print as you suggested. The marks are still there. Bummer, eh?

You did this with the backed film? Did you do it just with Wide?

Please do both backing and just Wide. Sorry for the trouble.


Also, post a photo if you could.

The other possibility is that there is a dirty encoder strip around that area of the print that isn’t showing up on more lenient printing (paper) but does on film.


I marked (in blue pen) the location of the problem band and fed it into the printer. (Printer head has been moved off to the side.)

Will do the Wide (vs widest) gap and try again.


This is a photo taken after a test print with platen gap set just to wide. The 2 parallel lines are 3/8 inches apart and run top to bottom, not side to side. I don’t see the lines in the black areas surrounding the image on the pictorico.

Hey, Walker. There is some crud on encoder strip. (I didn’t even know there was such a thing until half an hour ago!) I could try to clean it with some alcohol and a lint free paper towel.

I will wait to hear back from you, in case you have any thing to add to the situation.


Yep. Looks like an encoder strip issue. Clean that with some rubbing alcohol.


Walker, thanks so much for your help. I cleaned the strip sufficiently to resolve the problem. Looks like I had gotten some Piezo Flush on the strip. Not much came off with the alcohol but I either got something else off, or enough of the Flush off to make a difference.

In case someone else has this problem and wants to know what an encoder strip looks like, I got enlightened by this video.

Happy Thanksgiving.