Reversal (positive) of a drainage culvert

Grocery Store Development – Part 1: Reversal Processing with Peroxide & Vinegar – By Josh Vickers

What if you could develop and fix film using only products from the grocery store?

What if some supernatural event caused every brick-and-mortar photography store to disappear in a puff of silver? What if you needed to develop film on the very same day, just about anywhere in the world, and couldn’t wait for chemistry to be delivered?

The idea began to nag at me a few weeks ago. I had only just learned about reversal processing, making a positive filmstrip instead of negatives, and the high price tag and hazardous materials of the kits to do it had me looking for alternatives.

At the time, I wasn’t even quite sure how the reversal process was accomplished. How do you switch what was exposed to light and what wasn’t? I might have just chalked it up to voodoo magic and moved on, but the desire to actually perform the process and satisfy my curiosity impelled me to do a bit of research. And doing so gave me a much broader understanding of development overall.

So, let’s break it down. Film is exposed to light. The silver halide crystals struck by that light become tiny seeds of metallic silver. Developer grows those crystals, so what was hit by light becomes black silver metal. Fixer dissolves the remaining silver halides. And voila, you have a negative image. If you are on this site in the first place, this is likely not news to you.

Where the reversal process differs is merely in the addition of a step. You develop the silver crystals as usual, but then… You dissolve them. You remove anything that had been struck by light from the film, as if you used an inverted fixer. But then you have nothing but unexposed silver halides on the film. How are you supposed to develop it?

You do something that feels very wrong.

You expose the film in the middle of the development process.

Now you have film that only contains exposed silver halides, which simply need to be developed. Having removed anything that was struck by light initially, the areas that usually would appear black in the finished product, you will instead turn the areas that usually appear transparent into black. You’ve created a positive image.

That’s all well and good, but how do you go about dissolving silver in the first place?

Oh. Sulfuric acid.

I nearly abandoned the entire idea, but still fascinated by the concept, I kept researching to see if others had found ways to do it that didn’t require anything terribly caustic. And of course, they had.

There were a few photographers that had bought bulk chemicals to create the chemistry needed to dissolve the metallic silver (a mixture confusingly called “bleach;” no relation), with varying degrees of safety hazards. One mentioned, almost in passing, that a heated mixture of hydrogen peroxide and vinegar would actually accomplish the goal, but that it caused tinted film and potential reticulation. He discounted the idea on that basis.

But frankly, this was a completely impractical process for me to be doing in the first place. I was not making slides. It was the joy of the experimentation that I wanted to experience. Tinted film and reticulation? Let’s call that “style.”

Before the day was done, I had spent three whole dollars on supplies and created my first reversal film.

Reversal (positive) of a tall flowering plant
Asahi Pentax K1000, Fomapan 400, developed in caffenol

I was so excited at my results that I posted a quick video to the Vintage Camera Users Facebook Group to offer to teach anyone that was curious about the process how to do it themselves, for 2.5% of the price needed to buy a kit, and with even less of the potential dangers to self or environment. There were several photographers that were at least curious, and that was all I needed to give it another shot, recording the process. A few even tried it, to my everlasting elation.

Here’s the process, developing in a Patterson tank:

1. Develop your film at +1 stop to make a fairly dense negative, then pour your developer into a temporary container.
2. Wash your tank, and pour in a ratio of 1:16 vinegar/peroxide 3% (the bleaching mixture) at about 100 F, for 6 minutes, agitating constantly.
3. Pour out the bleaching mixture and wash your tank.
4. OPEN THE TANK AND EXPOSE THE FILM AGAIN. I held it up to a light for about 30 seconds.
5. Respool it back into your tank, and start over, developing and fixing as normal. You can use the developer from your temporary container again. And that’s it!

My horizons had been broadened, not just in what things worked, but why they worked. And the seed of an idea had taken root. This was something I could do with things from the grocery store. From any grocery store, anywhere. I felt empowered, given the chance to have a much greater say in the results of my film. And I wanted more…

_josh vickers

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22 thoughts on “Grocery Store Development – Part 1: Reversal Processing with Peroxide & Vinegar – By Josh Vickers”

    1. Thank you! It will likely need a little bit of experimentation, especially if you are using a different film. Films with clear bases work best, such as Rollei and Ilford films. You can make a clearing bath to remove or reduce the tint, but I haven’t done this; I rather like the sepia look.

  1. “Once an idea has taken hold of the brain it’s almost impossible to eradicate” – Abraham Lincoln
    I believe everyone should have the knowledge to manufacture, for themselves, the basic components of everything they use.
    And this fits just nicely with that viewpoint! Looking forward to part 2

  2. I really have to try, thanks for sharing! To me the sepia tone would be rather a feature than a bug. One thing: I’d rather use citric acid instead of acetic. Should be OK since citric acid is used in various film processing products. Any reason why it should not be a good idea after all?

    1. I think it should work; metallic silver is dissolvable in citric acid, anyway. And I believe the peroxide merely acts as a catalyst. I suspect there would be a difference in the duration of the bleaching step, because the citric acid is likely more active than the vinegar. I would suggest trying it on a test roll of just a few shots. Let me know how it turns out!

  3. This is exciting! The one lab in the US that did reversal B&W processing just permanently closed down their line, and I’ve been researching alternatives with no success. Our septic system won’t tolerate anything highly toxic, so the expensive kits are out of the question (and seem to be pretty difficult to source anyway). Your method just might work for me, and I’ll need to give it a try. I’m eagerly awaiting Part II. Thanks for sharing this!

    1. You bet! It’s the least-hazardous method I had found so far. Though another photographer I know has been experimenting with a few crazier compounds with some success. You can technically get them from local sources, but for my money, I’ll be sticking with something that won’t eat my face.

    1. It is a lot of fun, if impractical! Pulling a roll of positives out of your development chemicals is a fairly crazy experience.

  4. James Summers

    Thanks for a great and intriguing article! Any tips on getting the exposed film respooled back into the tank?

    1. It isn’t the easiest thing in the world. Your emulsion will be wet, and easy to damage. If you have a transparent or steel spool, you might be able to to fog the film without taking it off the spool. Otherwise, it’s delicate work. Just keep in mind that there is very little haste required; anything left on the film needs to be exposed, so you won’t be messing up your images by leaving them out too long (as far as I know). Take your time and try to keep anything from touching the emulsion.

      1. James Summers

        Cool, thanks for that Josh. I had been wondering how critical the exposure time was or whether it didn’t really matter how long the film was exposed (within reason). I’ve a Paterson tank so I will try leaving the film in the spiral at first as if that works it will be easier than trying to get wet film back in the spiral. Many thanks again. I’m looking forward to Part II.

  5. Wow; I have not the slightest interest in trying this. And yet the brilliantly clear way you explained the process and what drew you to it makes this one of the most compelling pieces on 35mmc for a while. Your enthusiasm is wonderfully conveyed and the flower pic is great too; Thanks Josh!

    1. Aw, you’re a prince! Thank you so much. The next few parts of the series are already submitted, and I tried to keep the same level of detail and excitement. Especially when it gets to making your own fixers. 😀

  6. I’m really curious on how the developed film looks, do you happen to have a picture of those? Love the result and the underlying idea, keep it up.

  7. Do you think this can work with prints (paper)?
    Any difference in the process?
    I am beggining to do pinhole photography using paper as film.
    Thanks in advance.

    1. I’ve never had the chance to do paper prints, unfortunately. But then, if you were to run a reversal in some way on paper, you’d end up with negatives instead of positives, wouldn’t you?

      1. he would be shooting onto paper instead of film, this gives a paper negative.
        Instead of contact print them for positives he wants to reverse that same paper negative

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