Gives you a real appreciation for the technological powerhouse that Kodak was in its prime.
Edwin Land who started the company was an incredible talent and is really worth reading up on.
EDIT: the Caffenol wiki page[1] has a link to the original article from 1995 explaining how this works[2]
[0] https://www.caffenol.org/alternative-recipes/
- film has a silver halide emulsion in it
- silver halide converts to silver when exposed to light
- once you’ve taken your picture, you need to: 1) remove remaining silver halide that wasn’t exposed to light, 2) “fix” the remaining silver so it’s stable
The neat thing about chemistry is it’s very empirical. What your process is either works or not.
So would berry juice be better? Maybe? The only way you’d know is to try.
There's a developing stage before before your step 1).
Developing causes areas of silver halide that were, in effect, only partly converted to silver (the so-called "latent image") to undergo full conversion. It's quite a complex process.
Isn't that somewhat backwards? The developer converts exposed grains to metalic silver to create a visible image from the latent one, the stop bath neutralizes the developing solution, and finally the fixer dissolves unexposed silver halide.
> I will surely continue exploring the wide world of edible and potable things like coffee, red wine, tea … made some successful experiments with elderberry juice, rosemary tea, coca cola … next will be dark beer for sure!
https://www.caffenol.org/2012/09/20/a-coffee-with-no-1-dagie...
tells the sordid story of how Kodak just didn't care about the permanence of color prints until 1980 or so. Wedding photographers would be paid $1000's for their work but couldn't get materials to make prints which would last a lifetime. Martin Scorsese lit a fire under Hollywood's ass about the permanence of films, but for that industry, keeping films in a dark freezer turned out to be a practical and permanent solution.
If you screw around with developing film with unusual chemicals I'd be concerned about how long the prints last, however black and white film where the image is really printed in silver crystals is likely to be more stable than the color film systems where the chemical changes in the silver crystals are coupled to dye systems.
When I was a kid I extracted dyes from flowers and did experiments with them and one conclusion was that they just don't last.
Unfortunately, these companies had to set up supply chains for manufacture of the necessary chemicals, and those supply chains run the risk of evaporating as the demand for film declines. Polaroid already fell to this... you can't buy Polaroid film any more, and it can't be manufactured, because the required chemicals are simply not available. The production line has been purchased and restarted but it's not the same film.
https://en.m.wikipedia.org/wiki/Ilfochrome
RA-4 color paper, on the other hand, is alive and well; most of it gets used for digital prints, exposed by laser printer and then developed.
If magic was real, wouldn't those who knew how to use it figure out how to profit off it on a wide scale? Flying carpets? Too much time investment for too few trips. Aluminum "wings" that fooled even Bernoulli... no there's a business that continues to make billions. DNA testing? Don't get me started about prepackaged identity spells.
:)