Quote Originally Posted by Alan Johnson View Post
I mixed an ascorbate clone of FX-1 where sodium sulfite was replaced by sodium ascorbate: Metol 0.5g ,Sodium Ascorbate 5g ,Sodium Carbonate 2.5g ,water to 1L ,pH about 11. Delta 100 was developed in this 18m 68F. It gave somewhat overdeveloped negs with a high EI.
It is known from Crawley's experiments that if there is no sulfite the action with metol and carbonate alone is very slow.Therefore it follows that both the sulfite in FX-1 and the ascorbate in the clone must be participating in the development,but if by chemically similar reactions seems not to be known.
BTW this clone of FX-1 is similar to a developer listed by Patrick Gainer in his article "Vitamin C developers" at Unblinkingeye.com.
You write that the ascorbate clone of FX-1 gave a high EI. How did you measure this, by comparision to another developer? In my experience valid comparisons of EI require very tight controls in exposure and development.

Sandy King