Kallitype beginner question - can't get print to completely clear

Hi, this is my first time posting in Photrio. Best wishes!

Anyhow I'm just getting started with Kallitype printing and and am running into an issue - I can't get my paper to completely clear. I've attached two images to illustrate.

I'm using Bostick & Sullivan chemistry for both coating and development. To clear, I'm using a citric acid solution followed by two separate EDTA solution baths. 4 minutes in each totaling 12 minutes. I'm then fixing for 2 minutes in sodium thiosulfate.

I've tried doing the entire process with distilled water because I've read that contaminants in tap water can potentially cause this clearing issue. No luck. I've also taken extra care while coating to ensure that there is no fogging.

The first image that I've attached is coated paper that went straight into the developer without any UV exposure whatsoever. My expectation is that the paper should clear completely under these circumstances? The second image was obviously exposed and is exhibiting the same issue.

I assume I'm doing something silly, but am running out of ideas.

Thanks for your help!

EDIT: I'm using Stonehenge Polar White paper and working under safe lights in a dedicated darkroom.

What paper are you using?

What lighting are you working under? If you have LED, fluorescent lights, or your tungsten lamps are too high wattage in your DR then the stain is actually exposed coating. I have a 40 watt yellow tungsten bug light that I work under, and turn off all my other lights.

Andrew O'Neill said:

What paper are you using?

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Hi Andrew, I've been tearing down sheets of Stonehenge Polar White.

Rick A said:

What lighting are you working under? If you have LED, fluorescent lights, or your tungsten lamps are too high wattage in your DR then the stain is actually exposed coating. I have a 40 watt yellow tungsten bug light that I work under, and turn off all my other lights.

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Hi Rick, I'm doing my work in a dedicated darkroom with safe (bug) lights.

saddlemeyer said:

Hi Andrew, I've been tearing down sheets of Stonehenge Polar White.

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That possibly could be the issue. In my experience with making Kallitypes (and several other Alt. processes), it's picky about paper, and its internal sizing. I used to print on Stonehenge Rising, but had to first give it a bath in an acidic solution, usually a 10% Sulfamic Acid bath. After that, clearing was not an issue, and the increase in Dmax was astounding. You could try a pre-bath in Citric Acid, rinse with water, then hang to dry, before sensitising.
Or... do what I did. Bite the bullet and buy paper intended for Alt like Hahnemuhle Platinum Rag, or Revere Platinum.

I would rule out the bug lights. I used them for years until it burnt out. Wanted to make a print and couldn't wait to get a new bulb, so I went ahead under 40W bulb. No issues. Never bothered getting another bug light

First thing to try: acidify the paper, and see if that helps.

Second thing to try: If you're re-using developer, try fresh developer instead. I get staining if I re-use developer, so I always use fresh. Not much is needed; the developer is just a solvent for the exposed oxalate.

Third thing to try: agitate the print constantly during development and clearing. I find that clears the paper much faster.

Fourth thing to try: add a few drops of peroxide to the developer. If this works, the problem is fog, not stain. Fog is due to either bad oxalate or exposure. The remedy is obvious in both cases.

Fifth thing to try: change paper. You can ask for recommendations here.

Let us know how you get along.

This looks more like spontaneous formation of silver rather than uncleared iron. Silver nitrate can reduce to silver in the paper even without exposure (dark reaction) or even in absence of any ferric oxalate which can be exacerbated if the coated paper is kept for a extended period of time before exposing and processing. You can judge this by coating just with silver nitrate and see if you get similar fog by processing without exposure as you did with the mixed sensitizer, similar to something I found in this study:


Paper is a major factor and as it can be seen the best outcome was for the paper that had no buffer (COT 320.) My theory was there is chemical reduction of silver nitrate by cellulose in the paper which is favored by an alkaline environment. So the suggestion to use alternate paper specifically made for alternative processes without buffering agents (the usual suspects) would make sense. If you want to use your current paper, you can either neutralize the paper as Andrew suggested or perhaps add some citric acid or oxalic acid to the sensitizer itself - I have tried the latter on some of this staining papers with silver nitrate only and found it does work to minimize the dark reaction. You will need to play with the amount as it will also make the sensitizer slow with contrast going up, again based on my experiene with salt-free salt prints.

Good luck!

:Niranjan.