Developing Film in Cannabis

I made a cannabis-based film developer and processed over a hundred test shots with it.

In this article, I’ll share the results from my new Sativa Cannanol film developer, along with a recipe so you can make it at home. You’ll also see how this cannabis-based extract stacks up against a commercial developer and various phenol-based solutions, like coffee, moss, fir, cedar, blood, pond water, EpiPen, and pee.

Plus, you’ll learn about the ethanolic extraction method and various ways to make and improve your own organic homemade developer.

In this article: Cannabis: an ideal film developer candidate? Can you develop film in weed? Sativa Cannanol with Ilford HP5+ sample scans. Determining the development time for Sativa Cannanol. Sativa Cannanol vs. other organic phenol developers. Ethanolic extraction. How cannabis/phenol film developers work. Sativa Cannanol film developer recipe. What we’ve learned & tips for improving your phenol developer. Project videos. Acknowledgements. Support this blog & get premium features with GOLD memberships!

Cannabis: an ideal film developer candidate?

Factory-made chemicals are often the easiest, fastest, cheapest, and best-resolving solution for developing black-and-white film.

My Vancouver lab uses Ilford DD-X, which yields excellent results in most cases. I just finished a bottle of Ilford Ilfosol 3, which was recommended for better results with my black-and-white film that expired in 1992.

But black-and-white film developers can also be made at home. The most famous recipe is Caffenol — a simple mixture of instant coffee, vitamin C, and washing soda. Recipes that use beer, wine, garlic, and other organic compounds can be easily found online. Yet no one seems to have attempted to develop film in weed, according to the English internet (I’ve been recently pointed to Maconhol). That’s despite the plant’s 3,000-year history of cultivation and increasing availability after 95 years of prohibition.

Cannabis is legal in Canada nationwide, and it’s relatively inexpensive. Plants and seeds can be bought at nurseries and grown at home, yielding over 100g of dried flowers for less than $100.

Dispensaries will often sell dried flowers for about $5-10 per gram, which is a lot more expensive than growing, but also less hassle and smell. But how much weed do you need to develop a roll of fim?

It turns out that Cannabis sativa strains are rich in phenols (>1800mg/100g by some measurements), making the plant an ideal candidate for film development. Back-of-the-envelope calculations suggest that we need less than an eighth of the amount of weed by weight than coffee to make a comparable developer. In other words, we only need 1.5g of cannabis to make a 300ml solution (which should be enough for one roll of film).

While the rough estimates ignore the exact chemical composition of each plant and the extraction methods, test results with film appeared very promising (I tried two different strains).

Can you develop film in weed?

Indeed, yes, you can develop film in weed. I developed multiple rolls of Ilford HP5+ in various cannabis-based recipes for this article. I was even able to reuse the same developer multiple times (though there was some loss of quality).

Cannabis is just one of the ingredients that Daren (@LearnFilmPhotography on YouTube and here), Yvonne (@YvonneHansonPhotography on YouTube), and I tried to develop our film with. Below, you’ll see the samples developed in weed alongside blood, pond water, pee (!), wood, and flowers.

Our tests involved taking over 200 35mm film exposures on 20 bulk-loaded short rolls of HP5+. In the end, each canister contained eight bracketed exposures of our model, Lily (@lilianlihua on Instagram), and a stationary object with consistent studio lighting. We used those test exposures to determine the best conditions for our experimental developers.

During this experiment, we found optimal extraction methods, which have significantly improved our results with all types of developers. I’ve also added a final bath specifically for the cannabis developer to prevent a very real problem of intense, unfixable clouds of debris.

Sativa Cannanol with Ilford HP5+ sample scans.

To figure out the best possible exposure, mixture, and development times for this developer, I’ve shot eight rolls of HP5+ and then one more roll of Kosmo Foto’s Agent Shadow.

Test exposures were bracketed:

Lily’s portraits were taken at -4 -2 +0 +2 +4 stops (metered with the Lumu iOS app and set manually on Pentax K1000 with the stock 50mm SMC Pentax-A 1:1.7). She was consistently lit with studio lights throughout the shoot. It took a while to get through twenty rolls like that!

We’ve also made a bunch of control exposures of a stationary object: my great-grandpa’s Voigtländer Avus. The camera was bracketed in 1-stop increments: -4 -3 -1 +0 +1.

The photos above and below are the best exposures from all the bracket tests on HP5+. Lily was exposed +4 stops above the box ISO 400 speed (i.e., rated as if the film is ISO 25). Although photos of her at EI 100 and 50 would have also worked.

 ☝︎ Further reading: “Pulling Ilford HP5+ to ISO 3.”

These images were taken on the same strip of film, developed in reused Sativa Cannanol for 420 seconds at 69℉. I’d expect brighter images when the developer is absolutely fresh, but I had a limited amount of weed for this experiment. Below, I’ll show you the effects of reusing the developer up to four times (and I’ll explain why I’m not sharing the results from a fresh developer first).

I scanned both of the above frames on PrimeFilm XAs at 5,000DPI in 48-bit colour. The film strips themselves had a slight plum tint, which yielded a light-green colour on the negatives when inverted. It was on-brand, and so I decided to leave that in.

✪ Note: I use this method to scan all film for my reviews, including all the frames of this experiment. It provides consistent results that make understanding and comparing the emulsion’s attributes possible.

I like how tight the grain looks on HP5+ with this developer. You can see lots of detail, even in significant enlargements. This is despite the developed emulsion appearing quite thin when compared to industrial developers and even Caffenol.

Up close, the grain looks a bit like the CineStill 50D’s. Individual granules are noticeable, but they appear closely packed, giving the image a smooth appearance without losing any contrast or sharpness.

I reused the developer for the above images, which resulted in the loss of some apparent brightness, and the negatives looked slightly thinner than initially. But it still worked, so I tried a few different techniques to extend Sativa Cannanol’s life. First, by developing film at a much higher temperature: 82℉ instead of 69℉.

✪ Note: In addition to the standard set of model poses and stationary object shots, we made creative use of the remaining frames on the short rolls as well as a variety of other experimental exposures at the set, at home, and on the street. I’m sharing a variety of photos here with the goal of making this article more interesting to read and browse. A set of standard test exposures compared side-by-side is also posted below.

As you can see, the hotter development temperature did little to improve the reused developer’s speed (the background in the photo above looks more than two stops darker than the first photo of Lily, posted above); its potency continued to decrease with each use.

I also tried to develop a few personal test shots on HP5+ for longer times. A macro shot of the sativa bud you saw in the poster above was developed for 42 minutes (stand, no agitation). Unfortunately, that fogged up the film to become exceedingly dense, which gave my scanner a lot of trouble. I could barely see the image against strong light. The resulting digitizations showed massive amounts of colour shifts (after equalization), which I kept since they looked somewhat interesting and worth sharing. ☝️

You may’ve noticed tiny specs all over the 42-minute stand development samples, which are an artifact specific to cannabis-based developers. While there was some debris in most organic developers we tried, cannabis flowers released their tiny, sticky hairs and pieces of material that aren’t strainable without proper equipment.

This is why the first use of Sativa Cannanol mix yielded a portrait that had an unfixable amount of grime:

That is not to say that the effect is uninteresting. Seeing images like that out of the tank of my first cannabis-based developer felt captivating. The colour shift and the grime gave the film a look I’ve yet to see from anything else.

But I wanted to get the most out of this developer, and thus, I continued to experiment with times and the process until I completely ran out of weed.

The first change I adapted was washing film with soap immediately after fixing. It’s important to note that delaying this step (i.e., letting the film dry and washing it later) is counter-productive, as the grime becomes permanently embedded in the emulsion.

Determining the development time for Sativa Cannanol.

Sativa Cannanol is not a strong developer, at least when used with the Acapulco Gold strain. This is why I’m glad that we heavily bracketed our exposures, although more work can be done in the future to determine the optimal box speed development time for HP5+ and other films.

Film density (i.e., how dark the highlights and the frames overall appear compared to the blank edges) was an important factor for determining an optimal development time. However, that wasn’t the only thing I considered. In fact, you’ll notice that after a certain amount of density is achieved on a negative, there’s no significant improvement to either film grain or the amount of visual information in shadows/highlights. And yet, the scans do show very plainly which frames turned out either too dark or too bright:

Having scanned all the negatives and inverted them, I’ve arranged the results in a grid. The most potent developers (when it comes to shadow detail resolution) are at the top, and the worst of the bunch are at the bottom.

I then used this visual guide to estimate a film exposure value with HP5+ that can produce a brightness similar to the box speed with a commercial developer.

For Sativa Cannanol, when developed for seven minutes, it appears that HP5+ needs to be exposed at ISO 25 (or +4 stops of exposure). A good scanner will let you shoot HP5+ at box speed (+0) and then adjust the results in post without significant loss of quality (our homemade developers seem to be significantly better than the commercial stuff at preserving shadows). However, one could say that if we are to judge by the overall brightness of the results, even more exposure is needed to match the commercial developer with the cannabis-based one — but that’s not what I’m using as a guide, I’m looking at shadow detail.

Sativa Cannanol vs. other organic phenol developers.

You may’ve noticed that Caffenol results (a simple mix of 15g of washing soda, 5g of vitamin C, and 12g of instant coffee) look brighter than the commercial developer, Black, White, and Green (by Flic Film) in the comparison grid above. While the store-bought stuff seems to make brighter results overall, we’re looking at shadow detail, for which coffee seems to be more effective.

Alas, weed isn’t very practical for developing photographic film. Unless you get it for free or cheaper than what I paid for it at the dispensary ($22.39 CAD/3.5g with taxes or $7 USD for a single roll of film). It’s not very potent, which will force you to shoot an ISO 400 film at EI 25 for good results. But you can certainly create detailed, well-resolving images with cannabis if you’re inclined to do so. And it works with the easy-to-remember 69℉/420s temperature/dev time numbers (all other developers in this experiment used 68℉/10m).

For this to work, cannabis has to be soaked in 99% alcohol (I used isopropyl from a local pharmacy), which gives the developer a very strong smell. But unlike other materials, the weed’s musk is strong enough to cover most of the alcohol vapour, which I think makes it a lot more tolerable. Once the alcohol evaporates, the developed negatives continue to smell a little like weed.