What is your method for making digital negatives?

[Larry McNeil]

I know a lot of you make digital negatives for various alternative print processes. The last time I made digital negatives was about four years ago, and things have likely gotten better since then. I made digital negatives for palladium and platinum prints and it was exceptionally difficult to make good negatives then. I had loads of flat prints with awful tonal ranges and the ratio for reject prints was astronomical.

At any rate, I assume that it is easier to make high quality digital negatives now. What process do you use and what media do you print on to make your negatives? Do you follow an established method or have you come up with your own solutions? Any current books, articles or websites to recommend for making digital negatives?

Thank you in advance,

Larry McNeil

[sanking]

I know a lot of you make digital negatives for various alternative print processes. The last time I made digital negatives was about four years ago, and things have likely gotten better since then. I made digital negatives for palladium and platinum prints and it was exceptionally difficult to make good negatives then. I had loads of flat prints with awful tonal ranges and the ratio for reject prints was astronomical.

At any rate, I assume that it is easier to make high quality digital negatives now. What process do you use and what media do you print on to make your negatives? Do you follow an established method or have you come up with your own solutions? Any current books, articles or websites to recommend for making digital negatives?

Thank you in advance,

Larry McNeil

Most people appear to use one of the following systems.

The first two methods, which involve making and applying a correction .acv curve in Photoshop, are about equally easy (or difficult) to learn. The third method is based on QTR and involves creating a correction profile for the printer.

Persons who own and use RIPs other than QTR may devise and use their own profiles.

All three systems work fine, but of the three PDN is IMO the easiest to learn and use, QTR is the most complicated.

I personally used PDN for several years, then tried and switched to QTR, but more recently switched back to PDN.

Sandy King


PDN
http://www.precisiondigitalnegatives.com/

RNP
http://www.inkjetnegative.com/images/RNP/rnp.htm

QTR
http://www.ronreeder.com/

[Larry McNeil]

Hi Sandy,

Thanks for the very insightful information. I'm curious as to what attracted you back to PDN. I have a couple of friends who prefer that method too.

Larry

Most people appear to use one of the following systems.

The first two methods, which involve making and applying a correction .acv curve in Photoshop, are about equally easy (or difficult) to learn. The third method is based on QTR and involves creating a correction profile for the printer.
I personally used PDN for several years, then tried and switched to QTR, but more recently switched back to PDN.

Sandy King


PDN
http://www.precisiondigitalnegatives.com/

RNP
http://www.inkjetnegative.com/images/RNP/rnp.htm

QTR
http://www.ronreeder.com/

[sanking]

Hi Sandy,

Thanks for the very insightful information. I'm curious as to what attracted you back to PDN. I have a couple of friends who prefer that method too.

Larry

Several reasons.

First, in spite of extensive testing of QTR with the Epson 3800 I was never able to get rid of the grainy look in my carbon transfer printing. I switched from MK to PK and tried many different profiles with the right blocking density but regardless of what I did my prints looked too grainy for taste. Perhaps if I had used another half ton of Pictorico and wasted several hundred more hours in testing I would have eventually found a profile that printed smoothly but alas, there is only so much time! And deep down I have come to suspect that the Epson driver is capable of smoother printing than QTR.

Second, PDN is a relatively simple method and with reasonable care one can derive a correction curve in two or three hours of testing. And on the second try I found a PDN color that printed in carbon transfer with no grain, as smooth as if printing with my LF negatives.

Third. I originally started using QTR because I was convinced by the argument that applying the corrections directly to the hardware with a printer profile, as in QTR, offered the possibility of greater control of tonal values than applying a correction .acv curve in Photoshop. In practice I did not find this to be the case and the prints I have made with .acv corrections curves are just as good in terms of tonal control as those made with QTR profiles.

QTR is a great software for making prints on papers, especially with split-toning, but for making digital negatives I found it to be less than perfect for my own work. And I would emphasize, my opinions are based on my work alone as I am aware of several experienced alternative printers who are very happy with QTR.


Sandy King

[MaximusM3]

Several reasons.

First, in spite of extensive testing of QTR with the Epson 3800 I was never able to get rid of the grainy look in my carbon transfer printing. I switched from MK to PK and tried many different profiles with the right blocking density but regardless of what I did my prints looked too grainy for taste. Perhaps if I had used another half ton of Pictorico and wasted several hundred more hours in testing I would have eventually found a profile that printed smoothly but alas, there is only so much time! And deep down I have come to suspect that the Epson driver is capable of smoother printing than QTR.

Second, PDN is a relatively simple method and with reasonable care one can derive a correction curve in two or three hours of testing. And on the second try I found a PDN color that printed in carbon transfer with no grain, as smooth as if printing with my LF negatives.

Third. I originally started using QTR because I was convinced by the argument that applying the corrections directly to the hardware with a printer profile, as in QTR, offered the possibility of greater control of tonal values than applying a correction .acv curve in Photoshop. In practice I did not find this to be the case and the prints I have made with .acv corrections curves are just as good in terms of tonal control as those made with QTR profiles.

QTR is a great software for making prints on papers, especially with split-toning, but for making digital negatives I found it to be less than perfect for my own work. And I would emphasize, my opinions are based on my work alone as I am aware of several experienced alternative printers who are very happy with QTR.


Sandy King

Hi Sandy,

I've always followed your writing and love your work. Just found this old thread as I am looking to embark into making digital negatives. I am using exclusively Jon's Piezography with two Epsons 3880 (one for sepia matte and one for selenium/warm neutral gloss). Can I use K7 inks with PDN or do I need to stick with QTR and drive myself crazy wasting Pictorico and ink?

Thanks very much for your help.

Max

www.maxmarinucci.com

[sanking]

Max,

I feel confident that you could make good digital negatives with QTR and the K7 selenium/warm neutral gloss set. The problem is I don't know anyone who is doing this so you will have to start from scratch in making your profile with QTR. You might have noticed that I am currently working on a profile myself for digital negatives the Epson 7600 and the K7 selenium set, though I am trying to use the matte black as I would also like to use the printer for making matte digital inkjet prints. The idea of using four to seven shades of gray to make a digital negative has in theory some clear advantages, but to translate this to reality may take some work.

PDN is a multi-component system and you could use parts of it regardless of the ink set in the printer, but in practice it is designed as a complete workflow where you are using color inks and the Epson driver.

Sandy

[MaximusM3]

Max,

I feel confident that you could make good digital negatives with QTR and the K7 selenium/warm neutral gloss set. The problem is I don't know anyone who is doing this so you will have to start from scratch in making your profile with QTR. You might have noticed that I am currently working on a profile myself for digital negatives the Epson 7600 and the K7 selenium set, though I am trying to use the matte black as I would also like to use the printer for making matte digital inkjet prints. The idea of using four to seven shades of gray to make a digital negative has in theory some clear advantages, but to translate this to reality may take some work.

PDN is a multi-component system and you could use parts of it regardless of the ink set in the printer, but in practice it is designed as a complete workflow where you are using color inks and the Epson driver.

Sandy

Thank you, Sandy, for the speedy reply! Was not aware of your latest effort on the profile with the selenium set but I would be very interested in hearing more about it since I have the same set up in the gloss printer with matte in the first position to be able to do matte prints with the set as well. I guess I could always ditch the sepia in the other 3880 and turn it back to Epson to use PDN but I really love that ink set. Do you feel that is worth the effort of doing that with PDN instead of fighting QTR or PDN with Piezography? Decisions, decisions..

Best,

Max

[sanking]

Thank you, Sandy, for the speedy reply! Was not aware of your latest effort on the profile with the selenium set but I would be very interested in hearing more about it since I have the same set up in the gloss printer with matte in the first position to be able to do matte prints with the set as well. I guess I could always ditch the sepia in the other 3880 and turn it back to Epson to use PDN but I really love that ink set. Do you feel that is worth the effort of doing that with PDN instead of fighting QTR or PDN with Piezography? Decisions, decisions..

Best,

Max

Max,

The thread is here if you are interested. http://www.largeformatphotography.in...ad.php?t=68303

I really can not answer the question about ultimate image quality re: QTR with K7 Piezography versus PDN as I just don't have enough experience yet. I have made some very nice prints with digital negatives with QTR and the Epson UC inks, and some very nice prints with digital negatives with PDN. Without question the PDN work flow is easier to master, unless you can find someone with a good QTR profile for the process you want to use. Unfortunatlely I just don't know anyone with a good QTR profile for printing digital negatives with K7 inks with either the 7600 or 3800 (3880).


Sandy

[sanking]

Matt,

I forgot to mention one thing about making digital negatives with K7 Piezography inks, and that is the fact that it is not possible to edit the K7 profiles with the regular QTR tools supplied by Roy Harrington. Instead, the K7 profiles were created by Vermong Inkjet with their own software, which I don't believe is available to an individual And even if it were Jon Cone suggests that editing the complex curves would not be feasible for most people.

At this time I have someone working with me in creating a digital negative profile for my carbon printing but it has turned out to be a fairly complicated endeavor. I must admit that had I know that the K7 profiles could not be edited with the regular QTR tool set I might have decided to stay with the Epson color ink set, or substitute that with the InkjetMall color ink set.

Sandy

[joncone@cone-editions.com]

Sandy,

The software we built here to make QTR curves chooses 256 precise points from over 64,000 possible points for each of the seven curves that make up a single QTR K7 curve. As a result we do not have three edit points to allow for QTR editing. But, the result of such precision is output that is significantly smoother and as perfect as one can get in a linearized output.

The only curve I have made for digital negatives is for the Epson R2400 printer which produces 13" wide films. The curve is for Pictorico and produces a gamma 2.2 linearization from the dMin of the film to a dMax of nearly 2.9. Within that range of tone, you could build a Photoshop curve to limit the inks into a useful range of density as well as apply a contrast change that relates to your particular paper and chemistry.

The 2400 curve for film took me three days to build...and I ended up making two ink modifications to two shades which are easy to do on your own. I am certainly willing to share this with anyone who wishes to have a digital negative system. Unfortunately, the R2400 QTR driver is quite different than the 7600, 7800 or 7880... or other printers for that matter.

I do not know how other customers of mine are making their dig negs with K7 and they are not readily sharing their information.

The basics of using QTR tools is to build seven overlapping curves of density that are nearly linear and then to process them through the QTR tools for linearization. There is ample documentation on that process. However, there are very few instruments that can be used other than a densitometer for film. QTR attaches to the EyeOne spectro... And the EyeOne does not read film with the QTR tools. So there is the challenge to use hand entered data from a densitometer.

I happened to use an old x-rite autoscan that reads strip film but had to use a Mac with OS9 in order to have a functioning driver. We keep this old Mac just for this piece of outdated hardware.

Having said that, a lot of QTR users trying to make film negs are assuming that the work is done in Photoshop. The first step actually, is to configure QTR as a linearized process using QTR curves (which have no similarity to Photoshop curves, and serve no similar purpose.) The QTR curve controls the output of each of the inkjet heads...and you need all seven working in unison to produce a smooth output.

A reconditioned R2400 printer and my pictorico curve will give you a base that when printed with a gray tone scale - will produce a smooth artifact free gradation from dMin to dMax. It will provide a traditional opaque style negative (like silver) - rather than UV blocking...

How to get something like this for your 7600 - I'm not sure how the R2400 curve would translate into being modified - even though I can modify it easy enough. I can also give you the recipe for the two shades mixing... but it's not a definite because the QTR driver is so different between these two printers. I would think it could possible work.

When I made the R2400 neg system and announced to the thousands of Piezographers if there was interest to make turnkey neg systems...there were just a handful who wanted to use it. Not enough for the development time involved. Most people using Piezography are very happy with the output - especially the glossy systems which are true replicants for air dried silver print. I suppose I should have asked users who still had their darkrooms instead - the enthusiasm may have been higher.

I wish I could help you more directly with your particular printer. We no longer have functioning 7600 K7 printers either in our studio or the r&d lab - so I can't even offer to devote the time to making a K7 film curve for you.

If the person who is helping you requires some assistance - have him contact me.

Best regards,

Jon Cone
Piezography
http://www.inkjetmall.com

Matt,

I forgot to mention one thing about making digital negatives with K7 Piezography inks, and that is the fact that it is not possible to edit the K7 profiles with the regular QTR tools supplied by Roy Harrington. Instead, the K7 profiles were created by Vermong Inkjet with their own software, which I don't believe is available to an individual And even if it were Jon Cone suggests that editing the complex curves would not be feasible for most people.

At this time I have someone working with me in creating a digital negative profile for my carbon printing but it has turned out to be a fairly complicated endeavor. I must admit that had I know that the K7 profiles could not be edited with the regular QTR tool set I might have decided to stay with the Epson color ink set, or substitute that with the InkjetMall color ink set.

Sandy