Digital negatives for carbon transfer printing:Agfa Copyjet / QTR / Epson 2100 (2200)

[banksy]

Well Ron, there's nothing to sign up for and it may seem worthless to you, but the script saves most people WAY more than five minutes. I've taught this QTR approach for over a year now in about 8 workshops, and I've found it's VERY intimidating for most beginners. What seems trivial to those in the know can seem impossible to those who aren't.

Is David's script publicly available?

 

[Bob Carnie]

I agree with Kerik here, we all are coming at these different processes, from very different backgrounds, What seems dead simple to me is daunting to others. Watching Kerik , Ike and Sandy prepare these negatives was an eyeopener, as even though I read Rons excellent book cover to cover before the week at photostock, I was still in awe of how easy and natural it seemed to these folks, and even after a week of seeing over 50 negatives produced, I know it would be a chore for me to duplicate it at my shop.
Ask me to make a 4ft x8ft mural with multiple contrast filters no problem, make a complicated image enhancment in PS, no problem,
describe how QTR works, forget it .

Well Ron, there's nothing to sign up for and it may seem worthless to you, but the script saves most people WAY more than five minutes. I've taught this QTR approach for over a year now in about 8 workshops, and I've found it's VERY intimidating for most beginners. What seems trivial to those in the know can seem impossible to those who aren't.

 

[sanking]

Ask me to make a 4ft x8ft mural with multiple contrast filters no problem, make a complicated image enhancment in PS, no problem,
describe how QTR works, forget it .

I just want to emphasize that if you print the Charthrob chart with your process, scan it and then run the analysis Chartthrob it will create an .acv curve that you can then smooth as needed, record input/output values and insert directly into QTR following that protocol. The end result should not be in theory any different from a curve that one would create using Ron's method or using David's script. The main issue is to remember when you are working in positive or inverted space.

To make sure you get a good scan take care to flatten the print and place a flat object (magazine for example) over it when scannig. This will prevent unwanted reflections that might distort the readings.

Sandy King

 

[clay]

You are quite right Sandy about reaching the same results using either Chartthrob or the Ike-u-lator script. The chief benefit to Ike's script is that he eliminates that "Am I talking about negative density or print density?" thing by doing it in his calculations.

 

[Ron-san]

Hi Ron,
QTR manual v3 you say? I'm not sure where on your qtr website it is?
Cheers
jacek

Hi-- The manual is on my website ronreeder.com on the homepage and also under the Articles section. Cheers, Ron Reeder

 

[Ike]

Curve building script

Hey gang, here's a copy of the script and step wedge.

http://www.davideisenlord.com/qtr/qtr.zip

You need to place the script in your photoshop scripts directory (Presets->Scripts)

Invert and horizontally flip the step wedge and print via your favorite QTR profile with your GRAY_CURVE set to "0;0 100;100". Print the resulting negative, dry, and scan. Crop the scan so it looks like the original and then select File->Scripts->Build QTR Curve

The script will generate a curves layer, open up the layer and tweek and save the curve. The resulting .acv file can be used in your QTR profile in the GRAY_CURVE field as outlined in Ron's excellent book.

Enjoy
Ike

 

[Tom Kershaw]

Ike,

Is Ron's book worth getting in addition to the Quadtone RIP guide on www.ronreeder.com ?

Tom

 

[Ike]

I guess that depends on your experience level; beginner, expert, etc. Its certainly worth it from the stand point that Ron has done a lot to further alt printing with QTR digital negatives.
Ike

 

[clay]

Ike,

You da man.

 

[clay]

I think you will find Ron's book to be a good addition to your bookshelf. He covers a lot in the book that is not included in his quick guide.

 

[Ron-san]

I think you will find Ron's book to be a good addition to your bookshelf. He covers a lot in the book that is not included in his quick guide.

Friends--

I am pleased that folks think there is still some value to be had from reading the Hinkel and Reeder book. Sadly it was a bit out of date the day it was published and is now very out of date in at least a couple of areas. Specifically, if you want to make digital negatives using the Epson printer driver (NOT QTR) I would recommend the article on my website (ronreeder.com)titled "Digital Negatives with the Epson 3800 and Epson printer driver" (the title is something like that).

If you want to use QTR, then much more up to date instructions are available from my website in "The QTR Manual, v3". I think I have learned a lot about QTR since I wrote the original article in the book and what I have learned is pretty much summarized in v3 of the manual.

Enjoy Ron Reeder

 

[Kerik]

I also recommend the Hinkel and Reeder book for those just venturing into making digital negatives. While some of it is now out of date as Ron says, it still provides excellent groundwork for understanding what the whole digital negative "thing" is about.

 

[R Shaffer]

Thank you Ike,

Looking forward to giving your script a go & interesting discussion as well.

 

[Tom Kershaw]

Ron,

I've been reading through your QTR article again and have a couple of questions:

1. Is the initial exposure step found by simply exposing the inkjet film (unprinted) & sensitized material combination to a standard f-stop timing sequence, to find that 15, 30, or 45 minutes is the correct starting time, or is there something I've missed in the profile writing stage?

2. In relation to the profile you walk through in the article, is adjusting the variables and constants to my [printer / inkjet film / printing medium] combination a matter of using the same type of QTR profile or do I need to make other adjustments not immediately obvious?


Tom

 

[pschwart]

If you have 8x10 in-camera negs with a DR appropriate for carbon or palladium, why not just put them in 3 mil mylar/polypropylene bags and start printing? You will always want to use the bags, even when printing digital negs. Learning to make digital negs is worthwhile -- I use them extensively -- but it is not a trivial task and will absorb a lot of your time.
FYI: my experience has been that carbon is able to render tremendous detail.
If you can see the dither pattern in your negs, then you are likely to see them in the print, even on watercolor paper using a diffuse light source like BL tubes.

I've started to consider producing digital negatives for carbon transfer printing, especially while learning, (less potential damage to original camera 8"x10" negatives), from 120 format scans. I do however have a few questions:

1. After firing up the Epson 2100 for the first time in a few months and printing with the Harman Crystaljet paper (much sharper print at 360 dpi compared to 300 dpi) I noticed that even at the very finest setting some dither / dot pitch is visible in the lightest areas. As Quad Tone RIP controls the printer externally to the Epson drivers, is this dither pattern something to be concerned about (i.e. will it show up) on the final carbon print?

2. If I do decide to make digital negatives I intend to start with Agfa Copyjet. Is there anything about the Agfa film that prohibits its use for making digital negatives for carbon prints that I've missed?

Tom

 

[Tom Kershaw]

If you have 8x10 in-camera negs with a DR appropriate for carbon or palladium, why not just put them in 3 mil mylar/polypropylene bags and start printing? You will always want to use the bags, even when printing digital negs. Learning to make digital negs is worthwhile -- I use them extensively -- but it is not a trivial task and will absorb a lot of your time.
FYI: my experience has been that carbon is able to render tremendous detail.
If you can see the dither pattern in your negs, then you are likely to see them in the print, even on watercolor paper using a diffuse light source like BL tubes.

I want to make digital negatives to print medium format negatives as most of my catalog is 645 and 6x6. I would need to expose new negatives and process for the higher contrast index.

I'll look out for the dither patterns. I'm not sure who the author was, but in one post someone made the comment that they could see the dither pattern in areas of even tonality such as sky with the Epson 2200/2100 in certain instances.

Tom

 

[pschwart]

Most of my negs are also medium format 6x6 and 6x9. Re dither: running a head alignment will sometimes get rid of the problem.

I want to make digital negatives to print medium format negatives as most of my catalog is 645 and 6x6. I would need to expose new negatives and process for the higher contrast index.

I'll look out for the dither patterns. I'm not sure who the author was, but in one post someone made the comment that they could see the dither pattern in areas of even tonality such as sky with the Epson 2200/2100 in certain instances.

Tom

 

[Tom Kershaw]

I've just printed out the Quadtone RIP 'calibration mode' graphic on Agfa Copyjet and got a rather faint and grainy looking image on the transparency.

A scan of the Copyjet film with a piece of A4 backing paper:

The QuadTone RIP settings:

Tom

 

[clay]

That is the wrong image to print- open the quad tone rip folder in and look in /curve design/images/inkseparation6.tif for a 2-black ink printer or inkseparation8.tif for a 3 black ink printer. And print this image in calibration mode. It should look like this:

 

[Tom Kershaw]

Clay,

I assumed the image I printed out was a standard graphic for the calibration mode. If I open the file you mention, and select 'QuadTone RIP Calibration' then I should get the image you have posted?


Tom

 

[Tom Kershaw]

The image file in Photoshop looks correct, the printout in calibration mode looks like this:

 

[clay]

The way it should look is that each row will be printed out in only one color with the percentage of ink increasing on each row as you move to the right. I am not sure what is going on with your print. But it appears that the QTR drive r is still printing out each row using all the inks for some reason. One problem I do see is that you are using the 7 ink separation instead of the 6 ink separation test page. You need to use the inkseparation6.tif file for the 2100..

 

[Tom Kershaw]

Clay,

The Epson 2100 has 7 inks.

Tom

 

[Tom Kershaw]

Since the last message I have installed QuadTone RIP on another computer (without Photoshop) and printed the calibration file via Mac OS X's 'Preview' application onto Harman Crystaljet Gloss. The Agfa Copyjet test is being printed at the moment and looks fine as well. Perhaps there is some issue with my QTR installation. As far as I know, the QTR calibration mode overrides other settings and should simply put the pure inks down onto the substrate.

Tom

 

[clay]

OK. I was thinking it was only 6. Anyway, it looks like you have it figure out. I have had to uninstall and reinstall QTR one time when it just started acting goofy. Sounds like it was some digital gremlin that got you. FWIW. I notice that on the problem computer you are printing through photoshop. Just make sure that you don't have the "Let photoshop manage colors" button checked and that "No color management" button is checked in the printer dialog.

Clay,

The Epson 2100 has 7 inks.

Tom