How to Develop Slide Film at Home With Rodinal and C-41

This article explains how to develop colour-positive (slide) film using common photography supplies to save money and avoid waste. It also a story of how I came up with this formulation with tips on how you can make it even better for your needs.

This is not a complicated process, but you should have prior experience developing colour-negative film at home. If you’ve never developed film at home, colour-negative film development is the best place to start.

The Rodinal-flavoured C-41 reversal process only needs a bottle of a very common black-and-white developer (in addition to the standard colour-negative film development kit) to produce positives.

In this guide: The problem with developing slide film at home. What is a C-41 reversal process? Why Rodinal? Solving reticulation and other issues. First developer times, temperatures, and technique. The best part: fogging (re-exposure). Second developer, bleach, and fix. Scanning. Push and pull reversal development. Potential future improvement: stain removal. More samples. Support this blog & get premium features with GOLD memberships!

The problem with developing slide film at home.

Photos taken on slide film aren’t just images; they are physical objects.

Slide film usually feels thicker than most colour-negative and black-and-white strips. It’s often high-contrast and extremely detailed. Very fun to hold and particularly satisfying to pull out of a development tank.

However, slide film can be challenging to process, as most labs either won’t accept it or take a very long time to ship it to a third party. Home development isn’t just cheaper — it’s a faster turnaround and an intimate moment with your images as you’d be the first to see them.

A proper E-6 development kit will do the job well (unless it’s a bad batch). Yet despite regularly processing dozens of rolls at home, I don’t have the space to store another set of chemicals. I am also concerned that my chemicals would expire before I could take full advantage of them.

An E-6 kit has roughly the same shelf life as a C-41 kit, which means I’d have to shoot and process 8-16 rolls of slide film within two months to make it worthwhile. Slide film is a lot more expensive than colour-negative film and harder to get.

There are four new slide film options in 2026: Kodak Ektachrome E100, Fujifilm Fujichrome Velvia 50, and Fujifilm Fujichrome Provia 100F. Outside the US, you may be able to find Velvia 100. All these films are often out of stock and cost $30 or more per roll.

While I love this medium, even when I was working as a software engineer with a decent salary, I could not justify spending over five hundred dollars every other month on colour film alone.

The alternatives are either to collect exposed rolls over months before developing or to pair up with other photographers. Those options could work for some, but I want the best possible experience: seeing my photos on slide film shortly after shooting them.

What is a C-41 reversal process?

C-41 reversal is an alternative to the standard E-6 colour-positive film development process. Both involve a minimum of three chemical baths: first developer, second developer, and blix. C-41 reversal also requires exposing film to light after the first developer (E-6 does not).

Last year, I realized that there may be a solution to my slide film conundrum. As I researched the process of developing Harman Phoenix 200 I as a slide film, I came across a few recipes that modified the standard C-41 process by adding black-and-white developer as the first step. This method is known as the C-41 reversal process.

According to various decade-old forums and Flickr posts, the proper E-6 process uses similar colour developer, bleach, and fix compounds as found in C-41 kits, plus a very active black-and-white developer.

Active being key as the recipes either required high heat or stand development — all at unusually high concentrations.

My first experience with C-41 reversal was rather experimental, where I adjusted the chemicals’ development times and film exposure to produce ideal slide densities and colours specifically for Phoenix 200. Yet knowing that the process should also work for slide film made me want to try that as well.

Why Rodinal?

Rodinal is one of the most popular black-and-white film developers on the market. It’s an easy-to-find, affordable chemical that practically does not expire.

Unfortunately, C-41 reversal formulas that use this developer are sparse and incomplete, with no definitive concentrations, temperatures, or development times. (I’m hoping to change that with this article.)

Over the past year, I developed a reversal recipe that integrates well with the standard C-41 process and temperatures (so, all chemicals are heated to the same degrees), can be completed in a reasonable time (it adds less than 10 minutes to the standard colour-negative development process), and produces what I think are good results.

✪ Note: Rodinal-flavoured C-41 reversal produces a slight blue cast and an orange tint in the highlights. It cleans up well with film Q (using the same technique as with expired film scans). It may still be OK to project, though I haven’t tested that.

But that’s not all: home development is an opportunity to freely push and pull film — a service that typically costs more or is simply not possible at most labs, particularly when it comes to slide film.

This came in handy when I ran a roll of Provia 100F through my new Kodak Snapic A1 — which has a fixed 𝒇9.5 aperture and 1/100s shutter speed, which is ideal for ISO 25-50 film in full sun. And so to avoid overexposure, I have also formulated a Rodinal-flavoured C-41 reversal recipe for pulling slide film one stop:

Solving reticulation and other issues.

Before I could commit a roll of pricy slide film to this experiment, I wanted to examine a few issues I’ve been having with the C-41 reversal process while working with Harman Phoenix 200.

Even the best recipes showed a distracting pattern once I enlarged them on a high-resolution scanner: reticulation.

Reticulation occurs when some film layers swell and shrink during development, creating an effect that makes images look “leathery” when seen up close.

Some photographers seek to achieve this look deliberately by developing in a mix of hot and cold solutions (which is not my objective). But the temperatures I used to develop Phoenix 200 were not unusual for that film — nothing over 40℃/104℉ — with only warm water baths in between, so it was a surprise to see.

Soon after, Phoenix Hawthorne published a guest post in which he used stand development to address the reticulation issue.

Alas, I am not as patient, so I continued to seek a solution that would not involve waiting for over an hour. Hawthorne’s post did point me in a new direction: developer concentration. According to him (and others), higher chemical concentrations can cause reticulation, just as heat and sudden temperature changes can.

So I’ve adjusted my dilutions, temperatures, and times in an attempt to minimize reticulation. As a result, either through those efforts and/or due to the more robust components within slide film (which is meant to be processed in very “active” chemicals), none of my Provia 100F scans showed any evidence of reticulation.

But that doesn’t mean I got the results that I wanted easily. The times, temperatures, and the concentration are the three-body problem of film development, which means I had to ruin some good photos along the way:

Most of my mistakes involved over- or under-developing film with the first developer. My approach was also somewhat costly, not just in terms of film wasted, but also in terms of my time and opportunity: my earlier success with Harman Phoenix reversal convinced me that a set of guessed values would be good enough to process an entire roll of vacation photos — it was not, as you can see from the mess above.

But after several tries (on smaller strips of film), I was able to get results that work.

First developer times, temperatures, and technique.

Positive exposure on film is created with the first black-and-white (active) developer. This is the same for E-41 and C-41 reversal, meaning that the second developer (or the normal C-41 developer), as well as bleach/fix times and temperatures, remain constant — even when the film is push- or pull-processed.

This means there’s nothing to learn or set up beyond the standard C-41 kit mix, aside from a bottle of Rodinal.