Pre-development bleaching to retain brighter highlights

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I tried this technique to retain brighter highlights while maintaining a lower contrast. Used 5ml, 10 ml of 10%stock potassium ferricyanide solution in 1 liter water. Tried soaking print for 30sec, 1 min and 2 min. then rinsed in water before developing normally. Results were a whooping disaster. Image looked very bleached and washed out. I read what Tim Rudman suggested in the Master Printing Course. The examples he had in the book were gret. Anyone tried this before? What did I do wrong? Any suggestions? Or are there easier methods to achieve this. Thanks

-- Mei Leng Lau (bohl-lau@erols.com), February 14, 2000

Answers

It probably depends on the type of paper used.

-- Tim Brown (brownt@ase.com), February 15, 2000.

Latent image bleaching is something of a 'black art' - difficult to find published times etc. You'll probably need to experiment quite a bit with dilutions and times - I've heard of much greater dilutions but I might be confusing this with something else. Also, most of the contrast control will happen in the shadows i.e., this is where you have the greatest latent image and this is where you will see the greatest bleaching action i.e., most lowering of contrast. Is that what you want? If you want crisp highlights (I presume you mean high local contrast in the highlight areas) with lower contrast in the shadows, you could try split printing with variable contrast papers also. Good luck. DJ

-- N Dhananjay (ndhanu@umich.edu), February 15, 2000.

Perhaps conventional bleaching after development will better achieve your goal. This way is easier to control since you can see the action and also paint the bleach on selected areas.

-- Michael Briggs (MichaelBriggs@earthlink.net), February 15, 2000.

I have an article on Latent Image Bleaching on my site at http://unblinkingeye.com. I summarize all the information I have found on the technique and give suggested dilutions and times for all the papers I have tried it on. I also provide references to David Kachel's original articles on the subject. As a general guide, chloride papers require a much higher bleach dilution than bromide papers. It is definitely a trial and error process when you first start, but once you are calibrated with a particular paper you should be able to get consistent results.

-- (edbuffaloe@unblinkingeye.com), February 19, 2000.

It sounds as though you missed a couple of steps in the formulation of the bleach solution. When I read the instruction, I get the following. To start, add 100g. of ferri to 800ml of water,dissolve and top off with water to get 1L. Second, 10ml of the above in 990ml of water. Now,take anywhere from 10ml to 30ml of your second step solution and add it to 1000ml of water. This is your working solution. As Tim said in his book, it's almost pure water. It sounds to me as if you stopped after dissolving the 100g. of ferri in the 1000ml(800ml+200ml)of water and used that as your working solution. Did you do the two additional dillution steps????

-- Rick Obermeyer (obermeyer_rick@si.com), February 24, 2000.


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