BB PYRO
The first time I saw this formula was in the instruction sheet for the old HRT BB series of plates when they were produced in Germany. So back in the 20th century I dubbed it BB Pyro, for Birenheide and Blyth Pyro, but I might be the only one calling it this. The original pamphlet did not give it a name. The current producers of the BB series of plates, Colour Holographic, recommend the orignal PyroChrome Developer for the plates now.
BB PYRO from Holographic Recording Materials, circa 1997:
PART A
15 g Pyrogallol
5 g Metol
One litre water
PART B
30 g Sodium Carbonate
7 g Sodium Hydroxide
One litre water
Mix equal parts together before use.
Development time:
5 minutes at 20C (68F) for BB series plates.
Agitation: Constant
Primary recommendation for developing the BB 520 and BB 640 materials. Follow with a rehalogenating/diffusing bleach for no emulsion shrinkage, or 'Chrome bleach for change of replay wavelength in the reflection mode.
Shelf life: Part A can last a few daysin a tightly stoppered bottle; Part B can last indefinitely. The combined solutions can last about a day in a covered tray, but it's better to mix the two parts together immediately before processing and use it only once.
Sources: Holographic Recording Technology brochure and Colour Holographics brochure.