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Film Development

Fixer Tester

As more and more negatives are fixed the concentration of silver increases in the fixer until it is exhausted.

TESTING THE FIXING SOLUTION :

There is a very simple test that can be carried out to test the silver saturation of the fixer and it is a reaction of potassium iodide to the silver absorbed into the fixer bath. By placing several drops of the Kodak Fixer tester FT 1 in the fix ( this is a 5% solution of Potassium Iodide) the concentration levels can be determined. If the liquid stays clear, the fixer is still OK, but if there is a thicker yellow white stain in the bath from a reaction with the potassium iodide then the bath is exhausted and should be discarded.

When you mix a new fixer solution it is also good practice to discard the stop bath and mix a new solution at the same time.

fixer tester

 

 

 

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