Two Different Tools for Your Darkroom
Bellini Phenidone A and Pyrogallol are both raw developing agents used in black-and-white film and print developers, but they serve very different roles in a formula. Phenidone is a soft-working, high-energy reducer often paired with hydroquinone, while Pyrogallol is a tanning developer known for its compensating effect and use in classic formulas like PMK. Choosing between them depends on the developing characteristics you want and the recipe you plan to mix.
What the Catalog Tells Us
- Bellini Phenidone A - 10g: This soft working developing agent is the another popular ingredient found in many film and print developers and no home developing cookbook is complete without it as, with the compound hydroquinone it reduces silver halides to elemental silver. Phenidone is a staple for mixing standard PQ (Phenidone-Hydroquinone) developers, widely used for its gentle action and compatibility with many film and paper emulsions.
Bellini Phenidone A - 10g - Bellini Pyrogallol - 50g: Pyrogallol or Pyrogallic Acid is a developing agent often used for its tanning qualities. Its most famous use of recent times was by Gordon Hutchings who invented PMK developer (its main ingredients, pyrogallol, Metol, and sodium metaborate). Pyrogallol is a specialist agent for compensating developers that also harden the emulsion, a property valued in alternative processes and high-contrast applications.
Bellini Pyrogallol - 50g
Key Differences at a Glance
Phenidone is roughly five to ten times more active than Metol, meaning you need very little powder per liter of developer. It is also a common alternative for people with Metol allergies or skin sensitivity. Pyrogallol, on the other hand, is a tanning agent that not only develops the image but also hardens the gelatin, which can reduce physical distortion during processing. The supplied records do not confirm exact mixing ratios or working times for either chemical, so always follow a trusted formula when mixing from raw ingredients.
Phenidone A vs Pyrogallol: Which Should You Choose?
- Best for everyday film and paper development: Phenidone is the more versatile choice. It works in many classic formulas (like PQ developers) and is gentle on emulsions. If you want a single raw agent for general-purpose black-and-white processing, start with Phenidone.
- Best for compensating and tanning effects: Pyrogallol is for specific looks—compensating developers that retain shadow detail while controlling highlights, and for processes like platinum printing where a tanning developer is part of the recipe. It is less common for routine development.
- Allergy consideration: If you have a known sensitivity to Metol, Phenidone is a direct substitute. Pyrogallol does not address that allergy and has its own handling precautions.
Mixing Considerations
The supplied records do not include preparation instructions for either chemical. When mixing raw developer chemicals, always use accurate scales, distilled water, and follow a published formula. For Pyrogallol, the catalog notes a typical pyro-metol formula for platinum printing (similar to Wimberly's W2D2) that uses Metol, sodium bisulfite, and Pyrogallol in solution A, with sodium carbonate in solution B. Phenidone is often used in Ilford PQ formulas, but the exact recipe is not included here. Without full instructions, weigh and mix with care, and store raw chemicals in labeled, airtight containers away from moisture.
Final Thoughts
Bellini Phenidone A and Pyrogallol are not interchangeable—they solve different problems in the darkroom. Phenidone is a workhorse for everyday development, while Pyrogallol is a specialist tool for compensating and tanning developers. Your choice depends on the formula you want to mix and the effect you need on your film or paper. Both are available from Firstcall Photographic as raw chemicals for home darkroom chemistry.
