I experimented with this idea this week and I think I found something interesting. Same original formula of ferricyanide and ammonium ferric citrate, but adding citric acid and reversing the part that goes on first. I did the gelatin sizing first. Then 3x 12 drops of ferric plus 3x 1gram of citric acid. I coated the paper in that and let it dry. I tried to see if an image was forming using my 4000 lumen projector and nope, nothing. I mixed the process! But previously using the original formula I could do a decent exposure between 1 and 4 hours. So I took another such paper with the ferric already on the sizing and I mixed citrate 12 drops to 1 gram of citric acid plus equal volume water. The sizing melted immediately and I used a roller to mix the stuff together. Then I used a paper towel to clean off the excess. The paper looked almost white as if there was nothing on it just like in your other videos. I then calculated that I might need 1hr to match your exposure on the 4000lumen projector, but to my surprise it exposed in 8 minutes. I let it go until 15 minutes to be sure and I ended up with a heavily over exposed print. The material was still moist when I exposed it which may also play a role. This 8 minutes exposure at 4kL would be 8/127 in full sunlight or about 4 seconds! I will try that. Isn't that good enough for in camera cyanotypes?

@saidanehabib

3 ай бұрын

The shortest time I had to successfully produce a real in-camera cyanotype was around 20 minutes. Check if you see these links from a few years ago: facebook.com/photo/?fbid=10156524653041924&set=pcb.2737734742978532 facebook.com/photo?fbid=10156524653716924&set=pcb.2737734742978532

Thank you mr Saidane!! it was great help. I was wondering about exposure timing, i did from 30s to 3 mins under the bright sun in Vietnam. But it seem lack of contrast and pretty dark :(

Mr. Saidane... You'll forgive my ignorance on this cyanotype process, but... why the gelatin sizing when it is generally considered unnecessary to do so? And have you looked at this process's ability to accept toning? Thank you, and your rapid cyanotype process has saved an enormous amount of time, and so, thanks again. 🙂

@saidanehabib

Жыл бұрын

Thank you so much for pointing this out, you are absolutely right. Most people don't size for cyanotype, but I do because I get stains on my final prints, it could be due the kind of paper I use. Someone asked me if I size in this process so I mentioned in the video. I'll make a video later and show the difference when sizing and not. This process accepts toning, however using solution "A" and a watercolor or a pigment of your choice you can layer many colors, actually you can produce tri-color prints I use PVA size for sizing my paper, fabric, and wood. Have a great weekend.

@svurskasvurska8019

Жыл бұрын

​@@saidanehabib Hello, Habib. Thanks for that. The guy at Prussian Blue noticed the issue of staining, especially with the New Cyanotype formula or anything using oxalic acid, especially one he derived from your rapid formulation. He calls it Blue Flash. His initial wash after the development with potassium ferricyanide and oxalic acid is cleared with a citric acid wash and seems to solve the problem, but your paper and his may be completely different. Not sure. Thanks for all of this. Time to do some experiments. 😊

@saidanehabib

Жыл бұрын

@@svurskasvurska8019 Thank you so much, good luck in your experiments.

Hi, why gelatine in this case ?

@saidanehabib

Жыл бұрын

Hello, it's a good question and thank you for asking. While doing more tests on the CHIBA process, I had the idea to add potassium ferricyanide to it's ingredients and it worked well giving photo like prints. So I decided to share the experiments.