Tell apart Fixer and Developer in Analog Photography

This probably happens to every analog photographer sooner or later. You finished developing your black and white film and you don’t remember in which container the used developer and in which the fixer is. You want to reuse the fixer but you don’t want to put your film into used developer in the next session.

There is a simple trick: Put some exposed black and white film into the unknown substance for 1-3 minutes. If it turns black then it was developer. If the exposed film gets a clear base then it was fixer.

This sounds simple but for beginners it is unclear how exactly it should look. Therefore, I uploaded the results of my test. The first film snippet was in developer for 3 minutes and became black. The second snippet was in fixer for 3 minutes and became clear. The third and forth snippet was in the unknown substance for 3 minutes and did not change its appearance at all!

Example of exposed film
The first film snippet was in developer and became black. The second snippet was in fixer and became clear. The third and forth snippet was in the unknown substance.

That probably means that the unknown substance was more or less water. I think it is wise to be cautious if you don’t remember what is what. Fixer is not very expensive in the end. This trick can help if run out of fixer though!

Do you have Questions? Send an E-Mail to max@maxammann.org