Nothing so interesting! I just like to use paper negatives, which are fine with FAC using the sun but a bit too slow to print using my BLB bulbs. FAO makes them doable under my BLB lights....Looks like you are into something very interesting. Are you making Cyanotype positives by any chance?
Nothing so interesting! I just like to use paper negatives, which are fine with FAC using the sun but a bit too slow to print using my BLB bulbs. FAO makes them doable under my BLB lights....
This thread is really interesting!
Hi, Ned:
Don't you get insoluble precipitates when adding ferricyanide to the FAO?
:Niranjan.
Out of curiousity, I took a sheet of cheap copier paper, coated, exposed, developed and washed it.....
...Would be interesting to a print a digital negative printed on copier paper and then make a FerroBlend print also on copier paper.
After exposure of 15 minutes:
Hi Niranjan,
I found that if I add some CA first, I can avoid the ferrioxalate precipitate but still get a boost in speed.
Unfortunately I am in team Koraks for now.
Not to go too far off this thread's topic.. I made a bottle of new cyanotype at the same time I was doing lots of testing with AFO. I had various problems with new cyanotype ( bleeding, PB finely precipitating out ) on the inexpensive papers I was using. Adding CA didn't solve my troubles. AFO + CA + pot ferri was very similar in terms of color, speed and contrast... after a lot of testing, I found an amount of CA that was a good compromise between preventing bleeding and getting the deep dark blues ( and preventing precipitates! )hmmm....in that case why do we need to do all that filtering etc when preparing Mike Ware's New cyanotype...might have to try this as well.
:Niranjan.
No, I brushed over it one time as in the instruction implied it would smudge. Taking for every brush new developer, then keep it flat in the tray for 5 minutes. Where it is yellow on the top picture it did seem to bleed.Did you also get a black precipitate when brushing the developer across the prints?
My exposed print is not looking like the one shown by Raghu, it does not have the color variation from the yellow to purple.
Here is the print she made:
This process looks very compelling, what would be the archival properties of these prints.. I have screen captured all the OP posts and some day give it a go in my shop.
I am not a chemist but I wonder if the composition of FAC could be playing role here.
Ah, progress!
@Cor, that's a compelling example, I think. You inspired me to give it another go with the Simili Japon paper, seeing that you produced a much better result than I managed yesterday!
Right; usually, I'm a bit skeptical when it comes to notions like "might my sodiumwhathaveyounitrate be bad", as we're usually looking at poor process control etc, but there's your argument that FAC is a poorly characterized substance. So I dug up another bottle of FAC from a different source, and sure enough, it seems to behave differently. The precipitation of black crud seems to be almost gone, even if I don't include chloride into the sensitizer. Progress, indeed!
So I've been doing some more testing, and so far, this is the best I can come up with:
View attachment 394871
A couple of caveats:
* Trying to match the real-world colors of the print on a monitor is one thing, then getting f*ing FireFox to also get the basics of color management is quite another. So no guarantees that you're seeing what I'm seeing.
* This print is very fresh and in its basis (at least the shadows) it's a cyanotype. So in a few days, I expect the shadow areas will have deepened and become more saturated.
Still, it's a major leap forward compared to where I left off last night. Here are the main things I changed on my end:
* Switched to another batch of FAC. This improved matters dramatically. I now was left mostly with significant fog in the copper image.
* To combat the fog, I dropped the ammonium chloride from the sensitizer, and instead added 100mg/ml sodium chloride to the developer. This seems to clear things up fairly well. I've not experimented with different ratios.
I should also note that I'm currently using the developer concentrate at ca. 1+1 instead of 1+4 as it says on the tin. I don't know if that makes much of a difference.
Also, I think it makes sense to keep development times as short as possible. I just did a test with 10 minutes instead of the 4 minutes the print above received. Print-wise, the main difference is that the 10-minute print shows a bit more fog. It's not 'developed more' or anything. The colors are the same, the transition from cyano to cupro is at about the same step.
I also noticed no benefit to acid-soaking my papers. The print above was 'virgin' paper. I did some 'acid-tests' and they basically didn't make much of a difference. What improvement I did see on one paper, I could easily match by adding NaCl to the developer and foregoing the ammonium chloride.
The paper @Cor used for his example and that I've also tested quite a bit with, Schut Simili Japon, fogs pretty badly. I've not been able to fix it. I've done most of my testing so far with Schut Salland, which seems to perform quite well. I just took a print from the wash made on a cheap Canson drawing paper and that also looks really well; maybe a little less saturated than the Salland print shown above, but also reasonably clean highlights.
Much of the fog seems to be suppressed by a combination of paper choice, adding sodium chloride to the developer and foregoing any ammonium chloride. IDK how important the latter is, but ammonium chloride tends to give me bad vibes when it comes to fog, although admittedly this is based mostly on my experience using it in silver gelatin lith printing - so quite a different application. Still, that ammonium ion is a bit of a rascal; better watch that guy closely. What fog remains, seems to be isolated along the edges of the area the developer was brushed on. So by brushing a little wider than the actual image area, most of the fog looks to be kept out of the image.
What I still haven't figured out is why the color palette that @Cor and I are getting is so different from @Raghu Kuvempunagar 's examples. Raghu's look so incredibly nice! The prints I've made so far are kind of...brutal. Very saturated, very in-your-face. It'd be nice to be able to tone this down a little. Maybe literally 'tone' it down? It's a new world - lots of parameters to play with.
Anyway...looks like something's starting to come together. I hope my notes above help fixing or avoiding problems for those who also want to give this a try. Sadly, I haven't the faintest idea what the difference between my two bottles of FAC is. One works, the other doesn't. That's about as much as I can sum up for now.
Struggles with FAC purity immediately bring to mind the New Cyanotype process. I wonder if similarly there’s an opportunity to move from FAC to Ammonium Iron Oxalate.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?