Digital Negatves, QTR, and the 3800

I just bought a 3800 and downloaded QTR for making digital negatives.

I read through Ron Reeder's PDF on how to create your own profiles in QTR for digi negs. As far as I can tell I followed his instructions exactly and created a test profile and attempted to print his supplied step wedge on inkpress transparency. When I printed the first one, the ink was laid down FAR to thick and it would simply smear off. My first thought was I printed on the wrong side of the media, nope. (Also tried a sheet of OHP so I KNEW I had the right side, same thing happened). Then I thought it had to do with the media type under printer features. I tried transparencies and matte paper. Neither helped. Then I thought maybe it was because I was trying to use matte ink on a glossy surface, so I switched inks, that didn't help. I looked back to the profile text file and it looked ok to me, nothing was not set, or set too high (at least to my eye, I'm new at this). I reinstalled the profile and tried one more time. Same thing, ink puddles that smeared easily. I even tried an ordinary positive print on epson media using epson drivers just to rule out a problem with the printer. That print looks lovely. So if you've acctually read through all this crap and have any advice I would love to hear it.

Andy T.

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Originally Posted by andy138

I just bought a 3800 and downloaded QTR for making digital negatives.

I read through Ron Reeder's PDF on how to create your own profiles in QTR for digi negs. As far as I can tell I followed his instructions exactly and created a test profile and attempted to print his supplied step wedge on inkpress transparency. When I printed the first one, the ink was laid down FAR to thick and it would simply smear off. My first thought was I printed on the wrong side of the media, nope. (Also tried a sheet of OHP so I KNEW I had the right side, same thing happened). Then I thought it had to do with the media type under printer features. I tried transparencies and matte paper. Neither helped. Then I thought maybe it was because I was trying to use matte ink on a glossy surface, so I switched inks, that didn't help. I looked back to the profile text file and it looked ok to me, nothing was not set, or set too high (at least to my eye, I'm new at this). I reinstalled the profile and tried one more time. Same thing, ink puddles that smeared easily. I even tried an ordinary positive print on epson media using epson drivers just to rule out a problem with the printer. That print looks lovely. So if you've acctually read through all this crap and have any advice I would love to hear it.

Andy T.

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Andy,

I'm not sure which profile you may have used but I think you have two problems going on:

1) I think Ron prints on Pictorico OHP and it maybe able to take greater ink loads than the inkpress transparency material.

2) So as a result you probably need to print the QTR file inkseperation.tif to determine what your maximum ink depsosition can be set to. Using a profile for another printer maybe a good starting place but some tweaking and testing will surely be needed.

You may also wish to visit HybridPhoto.com as I think Ron visits that site occasionally and maybe able to make suggestions. There are others there using QTR for digital negatives so they maybe able to help as well.

What process to you want to print with your digital negatives? Clay Harmon has posted a descriptor file for printing pure palladium with negatives made on an Epson 2200. That maybe a good file for you to look at if you are printing palladium.

Creating digital negatives made with QTR has a fairly steep learning curve but the first step is to determine the basic ink limits for your negative media. The next would be to determine the DR of the required negative and setting the ink load required for pure white on the print, this is done by setting the value for the DEFAULT_INK_LIMIT in the descriptor file.

Also are you printing with Matte Black or PK - Glossy Black? I beleive Ron prefers to use matte black.

Look on page 159 of Ron's book for more info about setting values that affect the mid-tones.

Regards,

Don Bryant

I am not familar with the specific media you have. It has also been a year since I last used overhead/transparency material. (So what good am I then, eh? :) :) )

But I have had better success using a dye based printer - an older Epson 890 - than with a pigment based printer on my transparency materials. May be a problem using pigment on the surface/material that you have? Haven't kept up to date, just a suggestion.

I also notice that the latest curves he has posted appear to be for the Epson 2400? I know the 3800 introduced a new dithering pattern for the K3 inks that might require some special adjustments? There are a few comments in his "Some New Notes" about moivng to a 7 ink process and the new K3 inks. I assume that is a bit dated, before the 2400 curves, but it may provide some clues as to his thinking about tweaks to the descriptor files for the K3?

Good luck!

Best,
Michael

I believe the problem lies in your transparency material and its inability to hold a heavy ink load (as Don said above). I use a 7800 with the K3 inks without a problem and I know Kerik Kouklis prints his digi-negs with a 3800--we are both currently using pictorico.

My first thought was that the inkpress material didn't hold ink as well as pictorico, but i tried a piece of pictorico OHP with the profile and same ink puddles. I'm going to keep working at it though, I'll figure out where I went wrong at some point. Probably after many sheets of expensive paper, and many drops of expensive ink.

Andy,

Each printer lays down ink differently, and of course it matters which inks. You have to go into QTR and adjust the ink limits so you don't put down too much ink on the media. I recommend you go to the hybrid photo web site.

Mike