How to develop slide film (E-6) at home
To develop slide film at home, you use an E-6 kit. A first developer makes a black and white negative image, a reversal bath makes the silver halide that is left ready to develop, and a colour developer turns it into the positive colour image; then bleach and fixer clear away the silver. The first developer sets the brightness of every slide, so it needs tight control: Kodak’s kit asks for 38.0 °C, plus or minus 0.3 °C.
What you need
- An E-6 kit. See the kits below.
- A developing tank and reels, as for black and white and C-41.
- Precise temperature control. A large container of water with a sous vide stick or another thermostatic immersion heater. Kodak’s instructions call for a temperature-controlled water bath for the solutions.
- A thermometer you can read to a fraction of a degree, checked against a second one.
- A timer, bottles for each working solution, and a jug of wash water kept at process temperature.
- Gloves, safety glasses and an apron, and a ventilated room.
Why E-6 is harder than C-41
E-6 is not hard to do. It is hard to do consistently, for four reasons:
- The first developer controls exposure. It develops the exposed silver into a negative. Whatever it leaves becomes the positive image. More first development means lighter slides; less means darker ones. Kodak says to adjust the first developer time to get the density you want.
- It needs tighter temperature control. Kodak gives plus or minus 0.3 °C for the first developer and plus or minus 1 °C for the colour developer. C-41 kits allow about plus or minus 1 °C for their only critical step.
- There are more steps. The full process has six baths plus a final rinse, against two to four baths for C-41. Each step adds a chance for a mistake or a temperature drop.
- The slide is the final image. A colour negative has room to adjust when you scan and convert it. A slide has much less: what you see on the light panel is close to what you get.
E-6 kits you can buy
Full kits follow the same sequence as a lab: first developer, reversal bath, colour developer, pre-bleach, bleach, fixer and final rinse.
- Kodak Color Reversal E-6 kit, made under licence by Photo Systems. It makes 5 litres of each solution and is meant for rotary processors, small tanks and other one-shot use.
- Bellini E-6 kit, a six-bath kit sold in 1 litre and 5 litre sizes.
Three-bath kits combine steps to make the process shorter.
- CineStill Cs6 “Creative Slide”: a D9 first developer, a Cr6 bath that does the reversal and the colour development together, and a Bf6 bath that bleaches and fixes. CineStill rates the D9 developer at up to 16 rolls, Cr6 at 16 or more and Bf6 at 24 or more. When this guide was written, CineStill listed the kit as out of stock.
- Arista Rapid E-6: first developer, colour developer and a bleach-fix.
A full kit takes longer but gives each bath one job and follows the process the films were designed for. A three-bath kit has fewer bottles and fewer chances to go wrong in the middle.
The E-6 steps
Kodak’s E-6 kit in a small tank, from its instructions. All times include 10 to 20 seconds to drain the tank.
| Step | Time | Temperature | Light |
|---|---|---|---|
| First developer | 6:00 to 7:00 | 38.0 °C ± 0.3 °C | Tank closed, in total darkness |
| Wash | 2:00 | 35 to 40 °C | Tank closed |
| Reversal bath | 2:00 | 35 to 40 °C | Tank closed |
| Colour developer | 6:00 | 38.0 °C ± 1.0 °C | Tank closed |
| Pre-bleach | 2:00 | 35 to 40 °C | Room light is safe |
| Bleach | 6:00 | 35 to 40 °C | Room light |
| Fixer | 4:00 | 35 to 40 °C | Room light |
| Wash | 6:00 | 35 to 40 °C | Room light |
| Final rinse | 1:00 | Room temperature | Room light |
| Dry | As needed | Up to 60 °C | Room light |
Three details from Kodak’s notes matter most:
- Choose a first developer time and hold it. Kodak lets you set the first developer anywhere from 5 to 8½ minutes, at a temperature from 36 to 40 °C, to get the result you want. Once you choose, hold the time within 5 seconds and the temperature within 0.3 °C.
- Agitate the same way every time. For an invertible tank, Kodak’s initial agitation is 7 or 8 inversions in 15 seconds, a tap on the bench to dislodge bubbles, and back into the water bath. In most steps you then give 2 or 3 quick inversions in 10 seconds at intervals. The reversal bath, pre-bleach and final rinse get the initial agitation only.
- Keep the lid on. You may open the tank after the reversal bath, but Kodak recommends keeping it closed to the end, so the tank loses less heat.
If a flowing wash is not practical, Kodak suggests three or four short changes of water over the wash time.
The three-bath route
With CineStill Cs6, only the first developer is critical. CineStill gives about 9 min 15 s at 40 °C for D9 diluted 1+1. Then the Cr6 colour and reversal bath for more than 6 minutes, at 27 to 40 °C, and the Bf6 bleach and fixer for 6 to 10 minutes, at 23 to 40 °C.
CineStill also gives a way to find your own temperature drop. Pour 40 °C water into your tank and go through the steps with water only. Measure the temperature at the end, divide the drop by 2, and add that to 40 °C. Start the first developer at that temperature.
Push and pull
Because the first developer sets the density, push and pull processing in E-6 means changing only the first developer. A longer first developer brightens underexposed slides; a shorter one darkens overexposed ones. Kodak’s fault table advises changes in 15-second steps. CineStill uses a weaker D9 dilution, 1+3, for a one-stop pull, and recommends its D6 or T6 first developers for pushing.
Work safely
E-6 chemistry includes developers you should keep off your skin and acids that can burn. CineStill’s own notes warn that the acetic acid part of its Bf6 bath may cause burns. Wear gloves and safety glasses every time, and an apron or lab coat. Work in a ventilated room, away from food, with equipment you use only for chemistry. Read the maker’s safety data sheet for each bottle, and follow your local rules when you dispose of used chemistry.
Common problems
From Kodak’s and CineStill’s troubleshooting tables:
- All slides too light. First developer too long or too warm, or the film was overexposed. Kodak: shorten the first developer in 15-second steps.
- All slides too dark. First developer too short, too cold, over-diluted or exhausted, or the film was underexposed. Kodak: lengthen the first developer in 15-second steps.
- Yellow stain. Kodak points to the pre-bleach: lengthen it, or mix fresh. An oxidised colour developer can also cause it.
- Overall blue or yellow cast. Kodak traces this to the colour developer’s alkalinity, usually from a mixing error. Check that you mixed it correctly.
- Opaque film with no image. CineStill: the baths went in the wrong order, or a step was left out.
- Milky or dirty-looking slides. CineStill: silver left behind. Return the film to the bleach-fix and wash it again.
- Black spots. Air bubbles that stopped the first developer, or dirt in the solutions.
When your slides are dry, scan slides with a camera explains how to capture them. Slides run from nearly clear highlights to very dense shadows, so exposure for film scans is worth a read too. For colour negative film, see develop colour film at home.