FX-39 is possibly one of the most carefully crafted B&W developers every created. It is the last in a long line of the FX series of developers, formulated by Geoffrey Crawley – a legend in the sphere of photographic chemistry and traditional black and white who optimised many black and white developers over a period in excess of 40 years. FX-39 is based on Willi Beutler’s Neofin Rot formula (which used to be the companion product to Neofin Blau/Blue – still available from Tetenal), however, Crawley improved the formula in almost every respect. FX-39 is a compensating developer and the compensating effect can be controlled with different dilutions. The only reason not to use FX-39 is if very fine grain is required, as it’s high degree of sharpness rendering is at the expense of the finest possible grain. It is superb with films such as Ilford Delta 100/400 or Kodak T-Max 100/400 but is also an excellent companion to more traditional emulsions such as Ilford FP4/HP5. It is possibly one of the greatest B&W developer formulas every created.
Originally, this was a product marketed and distributed by Paterson. When production moved to Adox, Geoffrey Crawley oversaw this transition and Adox promised to keep his “baby” alive! When Paterson ceased the distribution and branding of chemistry, Adox took up also this role in addition to production. It’s worth noting that Adox didn’t bother to continue to produce and distribute the other Paterson branded developer, Aculux, as this wasn’t really in the same league as FX39! Aculux was just a-another fine grain developer decent enough, but not startling.
Typical dilution is 1:9 – 1:19