How to Fix Black and White Film with Adox Adofix Plus
By Firstcall Photographic | Published: 2026-10-31
Category: How-to Guides
A step-by-step guide to fixing black and white film with Adox Adofix Plus, covering dilution, fixing time, clearing tests, and when to replace the working solution.
Quick answer
Dilute Adox Adofix Plus 1+4 with water for film, fix for the time your film and temperature require, and confirm the fixer is still active with a clearing test before each session. Replace the working solution when the clearing time doubles or after the stated capacity is reached.
Why dilution and fixing time are linked
Adofix Plus is a rapid fixer supplied as a concentrate. The 1+4 dilution is the recommended strength for film; 1+9 is also possible but is intended for paper. Using the weaker 1+9 dilution on film will slow fixation and may leave residual silver halides if you keep the same fixing time.
Fixing time depends on film type, temperature, and how much the fixer has been used. Follow the manufacturer’s time for the dilution and temperature you are using. If you change dilution or temperature, re-check the clearing time rather than assuming the old time still applies.
Rapid fixer versus standard fixer: what changes for you
Rapid fixers such as Adofix Plus work faster than standard sodium thiosulfate fixers, which shortens the wet time of your film and reduces the risk of over-softening the emulsion. The trade-off is that rapid fixers are more concentrated and their capacity is easier to exhaust unnoticed if you do not track use.
Standard fixers are more forgiving of long fixing times but require longer immersion. Neither type removes the need for a clearing test; both can be exhausted by silver buildup.
When to replace the working solution
Replace Adofix Plus working solution when the clearing test time doubles compared with fresh fixer, or when you reach the capacity limit stated on the packaging. For Adofix Plus, the catalog lists a capacity of 1.4–2 square meters of photo material per litre of working solution; translate that to the number of films you process and keep a simple tally.
Do not rely on colour change alone. Exhausted fixer can still look clear, and using it will leave undeveloped silver halides that stain or fade the negative later.
Step-by-step: fixing film with Adofix Plus
- Mix the working solution at 1+4: Combine one part Adofix Plus concentrate with four parts water at the temperature of your process. Mix only what you need for the session. Common mistake: using the 1+9 paper dilution for film, which slows fixation and risks under-fixing. Label the container with the dilution and date.
- Set the fixing time for your film and temperature: Use the manufacturer’s recommended fixing time for the 1+4 dilution at your working temperature. If you are unsure, run a clearing test on a scrap of the same film to establish a baseline time, then fix for at least twice the clearing time. Record the clearing time on the fixer container for future sessions.
- Fix with agitation: Pour the fixer into the tank and agitate continuously for the first 30 seconds, then for 5–10 seconds once per minute. Common mistake: insufficient agitation, which leaves localised exhaustion and uneven fixation. Keep the tank temperature stable; rapid fixers work slower when cold.
- Run a clearing test before each session: Take a small piece of undeveloped film and drop it into the working solution. Note the time it takes for the film to become clear. If this time is more than double the time recorded for fresh fixer, discard the working solution. A clearing test is faster and more reliable than counting films alone.
- Track capacity and replace when due: Keep a tally of the area of film fixed per litre of working solution. Replace the solution when you reach the catalog capacity of 1.4–2 square meters per litre, or sooner if the clearing test indicates exhaustion. Common mistake: topping up exhausted fixer with fresh concentrate without resetting the capacity count. Write the start date and film count on the container.
- Wash thoroughly after fixing: After fixing, wash the film according to your usual method for the recommended time. Residual fixer will eventually damage the negative. Common mistake: shortening the wash because the fixer was rapid; rapid fixing does not reduce the need for washing. Use a washing aid if your water is hard, but do not skip the final rinse.
Product facts
- Adox Adofix Plus Fixer - 500ml: Adox Adofix Plus is a high-capacity express fixer for black-and-white film, paper, and sheet film, usable in trays, tanks, and processing machines. One concentrate covers your film and paper fixing, so you can standardise your workflow and storage.
Adox Adofix Plus Fixer - 500ml - Adox Adofix Plus Fixer - 500ml: One litre of concentrate makes up to 10 litres of working solution at 1+4 or 1+9 dilution. Buying a 500ml bottle gives you enough working solution for multiple sessions, but you must track dilution and capacity to avoid exhaustion.
