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ghostcount
4-Nov-2016, 15:23
Stumbled on this guy's experiments on carbon printing continuous tone highlights claiming it's impossible to print them.

Experiment 1
https://www.youtube.com/watch?v=0IJJnR09em0

Experiment 2
https://www.youtube.com/watch?v=q3ZGkFIOWcw

Experiment 3 - (2 minute exposure on a step wedge)
https://www.youtube.com/watch?v=dUr82S_EKLU

Can tissue recipe and/or sensitizer dilution control continuous tone highlights beyond what he is printing?

Does his claim hold merit?

Haven't played around with this process in a while so pardon my lack of exposure in the process but do find his claim to be of note. He's got some nice set up though.

domaz
4-Nov-2016, 16:36
I have heard some carbon printers say they can't print skies or snow well. I haven't had the issue. I'm looking at a carbon print I did with a glacier in it (Mt Rainier) and I do see detail in the Glacier as well as the sky.

It's hard to determine why one printer may be having an issue another printer isn't. So many variables are involved (e.g pigment choice, sensitizing time, UV light source type etc)

One thought though, the use of solvents in the sensitizer is pretty widespread practice today because of convenience, but old sources like "A New Treatise On the Modern Methods of Carbon Printing" do mention using solvents like alcohol can dry out the tissue which perhaps could cause issues like this. I was also told to avoid solvents while learning the process at a George Eastman House workshop.

Jim Fitzgerald
4-Nov-2016, 17:42
I don't think it is impossible. I've printed images with snow that have plenty of texture. I believe I have an image with me that demonstrates the range of tones possible with carbon transfer. If you make it to the Symposium in Anaheim I can show you and address any concerns. There is a lot to consider with images like this. You can print continuous tone images, I've done it. Pure white snow to deep black shadows. Unless I don't understand continuous tone?
Is it easy? No. but then making a fine print never is.

Jeffrey Arthur
4-Nov-2016, 18:57
You sold me Jim. Your images of ice and snow are spectacular and definitely continuous tone.

Jim Fitzgerald
4-Nov-2016, 23:57
Jeffery thanks for that. Nice of you to say. I appreciate it. Those prints are the most difficult I've ever done.

Patrick13
5-Nov-2016, 11:20
I'm definitely going to try to make it to Anaheim, too. I've never seen a carbon print in person and the whole process sounds fascinating.

Jim Fitzgerald
5-Nov-2016, 11:43
Patrick, I hope you and others can make it. There will be some wonderful prints on display by some very talented artists. I will have several carbon prints on display and even one or two Platinum/Palladium prints from a digital negative. I can show what the possibilities are with traditional negatives and digital negatives.
I would encourage anyone who has wondered about carbon transfer to come by.

Vaughn
5-Nov-2016, 15:06
I have had little trouble with highlights -- unless the I over-developed the negative and blocked up the highlights. Using a minimum amount of pigment will help with the highlights...as the highlights will be made of a thicker layer of gelatin compared to a heavily pigmented tissue (when comparing areas of equal tonality). They will less likely to wash away during development. However, using a minimum of pigment presents other problems (and advantages). There will be a low native contrast to the tissue, for example.

sanking
18-Nov-2016, 15:32
[QUOTE

Can tissue recipe and/or sensitizer dilution control continuous tone highlights beyond what he is printing?

Does his claim hold merit?

Haven't played around with this process in a while so pardon my lack of exposure in the process but do find his claim to be of note. He's got some nice set up though.[/QUOTE]

Calvin's claim that it is impossible to print highlights in carbon is correct, so long as you understand that what he means by highlights is absolute paper white, or 0% density.

A carbon relief is made up of a hardened film of gelatin + pigment. At 0% there can be no film or pigment, as the mechanical nature of the process causes the film to break off at some point before you get to 0%, or paper white. Depending on skill, about the best that one can do in carbon printing is to keep the highlights slightly above paper white, perhaps at about 1%-2%. For nearly all images 1%-2% is more than enough so what many of us do is set the minimum density of our digital files at about 1% -2%, and this keeps the absolute minimum density from every going down to 0%. In many cases this is achieved in carbon printing by slight veiling of the images caused by fogging or chemical reaction, and in some cases it is achieved by the nature of the negative itself when it is continuous tone film.

In high end color printing dot negatives are used, which allow printing to absolute paper white. There is some question as to whether digital negatives, which have a stochastic pattern, function as dot negatives, or continuous tone. My impression is that they share printing characteristics of both types, but with slightly more affinity with the dot negative so that slightly better control of highlights is possible with digital negatives than with continuous tone film.

Sandy

ghostcount
20-Nov-2016, 10:13
Can tissue recipe and/or sensitizer dilution control continuous tone highlights beyond what he is printing?

Does his claim hold merit?

Haven't played around with this process in a while so pardon my lack of exposure in the process but do find his claim to be of note. He's got some nice set up though.

Calvin's claim that it is impossible to print highlights in carbon is correct, so long as you understand that what he means by highlights is absolute paper white, or 0% density.

A carbon relief is made up of a hardened film of gelatin + pigment. At 0% there can be no film or pigment, as the mechanical nature of the process causes the film to break off at some point before you get to 0%, or paper white. Depending on skill, about the best that one can do in carbon printing is to keep the highlights slightly above paper white, perhaps at about 1%-2%. For nearly all images 1%-2% is more than enough so what many of us do is set the minimum density of our digital files at about 1% -2%, and this keeps the absolute minimum density from every going down to 0%. In many cases this is achieved in carbon printing by slight veiling of the images caused by fogging or chemical reaction, and in some cases it is achieved by the nature of the negative itself when it is continuous tone film.

In high end color printing dot negatives are used, which allow printing to absolute paper white. There is some question as to whether digital negatives, which have a stochastic pattern, function as dot negatives, or continuous tone. My impression is that they share printing characteristics of both types, but with slightly more affinity with the dot negative so that slightly better control of highlights is possible with digital negatives than with continuous tone film.

Sandy

So in practice, one can find the threshold at which "paper white" begins base on a particular tissue, sensitzer dilution, etc. Perhaps having a black bordered mat board can provide the illusion of whiter densities on an image.:rolleyes:

Thank you Sandy for the clarification.

sanking
20-Nov-2016, 11:24
So in practice, one can find the threshold at which "paper white" begins base on a particular tissue, sensitzer dilution, etc. Perhaps having a black bordered mat board can provide the illusion of whiter densities on an image.:rolleyes:

Thank you Sandy for the clarification.

Correct, the highest highlight that can be printed, without mechanical break-off, depends on a number of factors related to process control, including tissue, method and type of sensitizer and dilution, type of negative, etc. It really is not necessary to leave a black border to give an illusion of white since with reasonable process control one can control highlight density to 1/2% - 1%, and the difference between 1/2% - 1% and 0% can only be seen when the two are directly compared.

I am attaching a scan I just made of a recent step wedge print, including a 21 step wedge where each step is different from the next by 5%, and a 50 step wedge, where each step is different from the next by 2%. As you can see, in each each case the step that corresponds to 0% (and paper white) is actually about 1%. I could adjust this down to about 1/2%, with a slightly greater risk of the mechanical bond breaking somewhere between 1/2% and 1%. However, in fact it is fairly rare that an image would need to show highlight even down to 1%. The carbon step wedge print were exposed with a digital negative made with an Epson printer using a custom QTR profile.

The concern about printing highlights down to 0% is an issue for color work, but in my opinion not with monochrome carbon, unless for some reason one just must print down to absolute paper white of 0%.

Sandy

ghostcount
20-Nov-2016, 13:46
Thank you Sandy for the in depth explanation. :cool:

Andrew O'Neill
21-Nov-2016, 18:00
It's very challenging, but not impossible... personally, I've found it way more challenging with inkjet negatives than film negatives...