A blended ferrocyanide print process

Andrew O'Neill

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My wife is pissed at me for not focussing on trip stuff...but it was eating away at me, so.... I snuck down to the darkroom, and tried again, with Ferroblend chemistry...but this time I mixed up the 5ml one shot developer instead of using the 100ml stock. Seemed to work like a charm this time. I would like to make another one using the 100ml stock developer, just to see if perhaps this was the issue, but my wife would probably leave without me
Anyway, here is the wet print... You can compare it to the fakeferroblend I previously uploaded.

 

koraks

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I mean the copper image that makes up the highlights, specifically. There's very little gradation to that part of the tonal scale, at least going by the digital version. Maybe it looks different IRL? IDK, it just looks a lot like my early attempts in that regard.
 

koraks

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I'm not really sure; in my case, I started trying different factors until the situation seemed to improve. I've documented what I did in those first few days here: https://tinker.koraks.nl/photography/fade-to-pink-a-brand-new-ferroblend-process/ There's a list of factors that I found or at least suspected to influence fog about 2/3 down the list. What makes this challenging is that the process is new, so there's just not a whole lot of experience to draw from, and we all have subtly different materials. For instance, variations in purity (qualitative and/or quantitative) of the FAC hasn't quite been ruled out at this point. Paper does indeed matter; that much is certain. BTW, I did some testing with acid-treated paper and for me, it didn't improve matters all that much. Some papers worked OK, some didn't work well at all.

I know it's a lame recommendation, but I'd suggest 'further testing'...

PS one thing that may be worthwhile is to try rule out the FAC factor by using Simple Cyanotype as a starting point. @Raghu Kuvempunagar has thoughts on this. I've not tried this angle yet; I believe he has and he might be able to give some suggestions on that route in particular.
 

koraks

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No, this one: https://www.mikeware.co.uk/downloads/SimpleCyan.pdf
It avoids the use of ferric ammonium citrate.

Andrew O'Neill said:
My FAC makes wonderful Cyanotypes, so I'm confident it's okay...
Click to expand...
Yes, I understand and I don't doubt it works for that purpose. There can still be differences between one batch of FAC and another, and these differences can affect FerroBlend. Mind you, that's a hypothesis at this point. It's in part based on the notion that FAC is a poorly defined substance from a chemical viewpoint.
When I started testing FerroBlend, I tried two bottles of FAC which looked virtually identical but that came from different sources. The prints I made with bottle 1 were foggy. The prints made with bottle 2 were much less foggy. Was the FAC the only or main cause for this? I'm not 100% sure.
 

Andrew O'Neill

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Oh wow, I didn't know about Simple Cyanotype! Doesn't sound so simple compared to the traditional Cyanotype, though! I don't have any Ferric Nitrate, but my supplier does. I've always sourced FAC from the same place. The only other place that would be reliable is Bostick & Sullivan, but due to current global situation...
Sadly, I cannot tackle this until I get back. Thanks, koraks! I'll be keeping a close eye on this thread.
 

koraks

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You're welcome! I still have in mind to test Simple Cyanotype as well, but we're in a similar boat w.r.t. the ferric nitrate. I intend to bundle some stuff I might need and then place an order for the whole lot. Just haven't gotten round to it, yet.
 

Andrew O'Neill

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I just ordered some Ferric Nitrate from Argentix. My son will hold be looking after our place, so he'll be able to receive it for me... Hopefully all of this will still be fresh in my mind, when I get back...
 
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Raghu Kuvempunagar

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NedL said:
Interesting... no excess pot ferri. I'm going to try soon... will start w/ OP recipe.
Click to expand...

In OP I have mentioned that Classical Cyanotype sensitiser can be used in this process i.e. without excess Ferricyanide in the sensitiser (see Note #3). However, when Classical Cyanotype sensitiser is used, Ferricyanide must be added to the developer. I have mentioned the amount in OP. I am aware that use of Classical Cyanotype sensitiser could make life simpler for those who don't want to maintain different sensitisers. I didn't recommend this route as, it can, at times, produce brushing artifacts with some papers (mostly smooth papers). But please feel free to try.



Mike Ware's Simple Cyanotype Part A (high contrast version) has worked well for me. To coat A4 sized paper use:
Simple Cyanotype Part A: 2 ml
Potassium Ferricyanide: 0.2 g
 
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Raghu Kuvempunagar

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Andrew O'Neill said:
Oh wow, I didn't know about Simple Cyanotype! Doesn't sound so simple compared to the traditional Cyanotype, though!
Click to expand...

The only difficult part in Mike Ware's Simple Cyanotype is having to work with Ammonia. However, Mike himself suggested an alternative to using Ammonia in his formulation, one that uses Ammonium Citrate. IIRC he named this variant Mike's Cyanotype. I haven't tried it but it's something one can consider if Ammonia must be avoided.
 

kaelynlayne

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koraks said:
I tried exposing humid paper. The results were horrible, indeed - worse than I had been getting otherwise.
Click to expand...

Humid paper is a problem with cuprotypes also. Ambient humidity doesn't seem to be too terrible once the paper is fully dried, but improperly-dried paper results (at least for me) in highlights staining so bad it's basically unworkable.
 

koraks

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kaelynlayne said:
but improperly-dried paper results (at least for me) in highlights staining so bad it's basically unworkable.
Click to expand...

This is actually quite interesting that you mention it, because maybe that's a factor I've not been able to control properly. Even 'bone dry' paper has some moisture content (IIRC it's somewhere around 6% or so?) I can imagine that this content varies a little depending on ambient conditions. In the FerroBlend process, maybe this is a factor as well?
 

nmp

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I have used ammonium bicarb aka baker's ammmonia and it also works fine.

:Niranjan.
 

kaelynlayne

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Andrew O'Neill said:
Humidity and moisture is bad with a capital B.
Click to expand...

If I want really clear highlights on a cuprotype, I add 2 parts baking soda to 3 parts copper sulfate. Interestingly, if I add baking soda, I don't need a developer. 3% hydrogen peroxide applied pre-toning works too, but not as well in my opinion.

I've added baking soda to a cyanotype solution before too, it does bleach but reverts back almost entirely after applying copper sulfate post wash. I wonder if something similar could be helpful here? I'd try it myself but don't have sodium citrate on-hand.
 

nmp

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Graham06

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I've been following this thread as a spectator, and I notice that the blue cyanotype part of the curve in some of the images posted here is much more contrasty than the orange cuprotype part of the curve, and that the contrast of each varies from person to person trying the process. "How does one control contrast in cyanotypes? and "How does one control contrast in cuprotypes?" might be interesting questions to help make this process easily reproducible. Perhaps the 'fog' some people are seeing is just a result of a low contrast copper portion of the image.

I think your test images should be printing a step wedge alongside the images you are using to test.
Printing the same image ( perhaps the OP would be willing to share a negative in digital form (that includes a step wedge and that he prints himself)) as a test that others can use as their first print to control and understand their process.

I don't see anyone doing it but I think digital linearisation would be a mistake at this stage ( you would do it at the end once you've done your best without it. )
 

koraks

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Yes, you're certainly right about the questions. As to the low-contrast and/or foggy cuprotype: yes, that too, although in my own testing I make a point of masking the borders and indeed including a step wedge. It's just too difficult to figure out what's going on without such benchmarks. It makes problem-solving a lot quicker if you can see what you're doing.

Linearization: yeah, as always, that's only feasible on a well-controlled process.
 

NedL

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I'll try to scan my 1st try tomorrow after it's dry. You all probably already know about this but the effect of ammonium chloride is kind of astonishing. I half expected the cyanotype to brush off or at least smudge when I applied the developer but it didn't budge.... I wish I'd known about this for some earlier work. It also changed the way the paper reacted to getting wet... this thin paper ( canson marker "pro layout" ) is prone to buckling but it was worse than usual. It even got a ripple while in the printing frame -- I've never seen that happen before. Several things went wrong that are all fixable... the paper got wavy when I applied the developer and the developer actualy depleted in some of the high areas where it ran off into the "valleys". I think there are easy fixes for these issues. I did not get anything like paper white and am interested in trying NaCl or KBr or anything else to preserve the whites....

Definitely fun to see the changes when applying developer and the colors are great! I'll be trying some more.
 
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