[alt-photo] Re: Vertical Banding in Prints Produced from Digital Negatives

[Greg Franco]

Hey Amy,

How many inks are you using?  Just black or full color set?  I have found 
banding to occur if only using one or two inks... hard to see with your 
eyes.. but the subtle differences in the UV absorption of each ink can cause 
the banding on your print when they are blended by the printer.  I had this 
happen when using just the yellow and black inks in a QTR profile for my 
Epson R260(since the other inks in the set didn't show much ability to 
absorb UV in my tests).  But the sum was greater than the parts and I ended 
up eliminating the problem by using profiles that used all 6 inks.

Greg

Message: 9
Date: Sat, 20 Feb 2010 17:58:12 -0500
From: Amy Holmes George <amyhgeorge at hotmail.com>
To: <alt-photo-process-list at lists.altphotolist.org>
Subject: [alt-photo] Vertical Banding in Prints Produced from Digital
Negatives
Message-ID: <SNT131-w41C7A142ED6BDE2F20054ACF450 at phx.gbl>
Content-Type: text/plain; charset="windows-1252"


Hello all,
I would gladly welcome any suggestions you may have regarding a recurring 
issue. I am printing digital negatives on Pictorico transparency film (Ultra 
Premium) with an Epson 3800 for use with pt/pd on COT 320 (and exposing in a 
Nuarc). For some reason, I am seeing a predictable pattern of vertical bands 
visible only in flat areas of high value such as the sky (please refer to 
attached jpg). This banding is not visible in the negative?even under 
magnification, and it is not specific to any one image. To me, the only 
logical explanation is my printer. So, I have performed a nozzle check, head 
cleaning and head alignment, but all the test results indicate no problems. 
I have even wiped down the interior according to the Epson printer manual 
instructions, and still the problem persists. What could cause this banding? 
I am out of ideas and feeling rather frustrated . . . help!?
Thank you,Amy