Moersch Tanol Speed is a two-part pyrogallol developer for black and white film, two 100 ml bottles.
What it is for
A faster version of the well-known Tanol: against it, this either extracts the film's full speed or lets you shorten development — your choice. The stain is yellow-green and on some films noticeably denser than usual. The maker aims it at films from ISO 25 to 400, which is most of the classics.
How to dilute it
It is a one-shot developer: mix the working solution, use it, discard it. That is the most predictable way to work — every film is developed in fresh solution, so times need no extending from roll to roll.
Storage
Sealed concentrate keeps well but dislikes air: the emptier the bottle, the faster it oxidises. Decant the remainder into a smaller bottle, or displace the air — that is what gets a concentrate to its last measure.
How it compares
If it is the pyro stain you want, choosing between Tanol Speed and Pyro 48 is choosing between speed and capacity. Against an ordinary developer both give what it cannot: controlled highlights with no masking or burning at the enlarger.
