rodeo_joe1 Posted July 9, 2018 Share Posted July 9, 2018 For the first time in my life yesterday, I came across a walnut tree in fruit. I picked a green walnut and peeled back a little of the husk, at which point my friend warned me that it would stain my fingers badly. She was right! The oxidised 'juice' quickly turned brown and then black overnight. The husk also smelled quite strongly of phenolic acid. Now most developing agents are phenolic compounds, and some, like pyro and paraphenylene diamine, will darken considerably with oxidation and stain. (PPD is used in hair dyes) So there's a similarity of characteristics between whatever chemical(s) are in walnut husk and two known developing compounds. The major chemical in walnut husk is juglone I believe, but this may not be the staining component. Anyway, I intend to extract whatever's water soluble in the walnut husk, activate it with washing soda and attempt to develop a piece of film with it. Has anyone else attempted this, or is it known already if walnut husk can be used as a source of developer? FWIW, Pyrogallic acid was apparently first isolated from oak galls. Link to comment Share on other sites More sharing options...
Moving On Posted July 9, 2018 Share Posted July 9, 2018 Don’t know about developer but I as a kid in Mississippi we always heard that yellow stuff was a cure for ringworm. Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted July 9, 2018 Author Share Posted July 9, 2018 Don’t know about developer but I as a kid in Mississippi we always heard that yellow stuff was a cure for ringworm. - Yes, been reading up on juglone, and it's being hailed as everything from a natural herbicide to a cancer cure! Don't know about that, but I'll give it a try as a developer.... if I can find that scrap FP4 I have lying about somewhere. Link to comment Share on other sites More sharing options...
paul ron Posted July 10, 2018 Share Posted July 10, 2018 hey joe cant wait to see the results of your experiments. as a kid we harvested black walnuts n had purple hands for weeks. The more you say, the less people listen. Link to comment Share on other sites More sharing options...
glen_h Posted July 10, 2018 Share Posted July 10, 2018 A more popular natural developer would be caffenol. Recipes There should be many plants that have reducing chemicals in them, though. -- glen Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted July 10, 2018 Author Share Posted July 10, 2018 A more popular natural developer would be caffenol. Recipes There should be many plants that have reducing chemicals in them, though. Caffenol isn't a proportionally staining developer though. And where's the satisfaction of curiosity in following that well-trodden path? Also, the active ingredient in caffenol appears to be caffeic acid, and coffee isn't even the best source of that chemical. Link to comment Share on other sites More sharing options...
glen_h Posted July 10, 2018 Share Posted July 10, 2018 (snip) Also, the active ingredient in caffenol appears to be caffeic acid, and coffee isn't even the best source of that chemical. Caffeic acid - Wikipedia says 0.03mg/100ml, which sounds kind of small for a developing agent. Caffenol might be somewhat stronger than ordinary coffee, but it still seems small. For comparison, D-76 has 5g/L of hydroquinone. Having never tried caffenol, does it also work with decaffeinated coffee? -- glen Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted July 11, 2018 Author Share Posted July 11, 2018 Caffeic acid - Wikipedia says 0.03mg/100ml, which sounds kind of small for a developing agent. Caffenol might be somewhat stronger than ordinary coffee, but it still seems small. For comparison, D-76 has 5g/L of hydroquinone. Having never tried caffenol, does it also work with decaffeinated coffee? - Apparently caffenol does work with decaf instant coffee. I tried developing in some left over strong filter coffee + alkali activator, and got nothing. I suspect there's some other byproduct of the 'instant' process that makes it a better developer (and a far worse tasting beverage!). FWIW, Phenidone is only needed at a level of 0.1 g/l or thereabouts, but needs a superadditive fellow developer like hydroquinone or sodium ascorbate to give a usefully dense image in any sensible time. Neither phenidone alone, nor sodium ascorbate, will give a useful image, but together they form a great team. 1 Link to comment Share on other sites More sharing options...
Dustin McAmera Posted July 11, 2018 Share Posted July 11, 2018 I recall reading accounts of developing film in beer, and in urine (I *think* this was on the now-defunct NelsonFoto forum). With any natural material, the strength is likely to vary from batch to batch, and you'll need to filter out fine solids before using it. I've never tried coffee as a developer. The attraction of instant coffee is just that you can get it anywhere, and the same brand should always give you the same strength. Alkali to make it with is somewhat less easy to get. I don't know of a similar corner-shop fixer. If someone were to show that you can clear film with diluted toothpaste or something, we could turn up and photograph in any little town, and process our film at the motel; but Joe will be laughing at us, as he does his film in a tree-house in the walnut jungle. Link to comment Share on other sites More sharing options...
Moving On Posted July 11, 2018 Share Posted July 11, 2018 recall reading accounts of developing film in beer, and in urine That makes for piss-poor prints...... Link to comment Share on other sites More sharing options...
glen_h Posted July 11, 2018 Share Posted July 11, 2018 Silver bromide - Wikipedia suggests that AgBr is soluble in liquid ammonia. It might also be soluble in ammonia solutions, like you find in grocery stores. -- glen Link to comment Share on other sites More sharing options...
Bill Bowes Posted July 11, 2018 Share Posted July 11, 2018 I did a 4 year trip with Caffenol & once the "kinks" are worked out, the negatives were very good. I found the stain was proportional if the chemistry bits n pieces were worked out for one brand of instant coffee & that brand followed. My "pick" was Folgers Dark Roast. YMMV. For those interested in a good, scientific bent, site, see CaffenolBlogPost by Rheinhold, a German fellow who has two blogs, the original in English, and now a more up-dated site, in German. I can remember picking walnuts as a kid, and believe the staining of a negative, should your "expieriment" work, should be very intense. Let us know. Bill Link to comment Share on other sites More sharing options...
glen_h Posted July 12, 2018 Share Posted July 12, 2018 It seems that AgCl is soluble in chloride solutions. (Like NaCl). I don't know about AgBr, though. I think I remember stories about navy photographers using sea water. It might take longer, and need higher concentration, though. -- glen Link to comment Share on other sites More sharing options...
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