Chemistry fundamentals don’t change, not in 70 years. Few mature subjects re-define their doundations, certainly not the theories. The practices change. Photographic chemistry as an industrial process has changed greatly since 1950. Even those changes are not as great as an enthusiastic, excitable weekender may think. The laten image must be “amplified” in a developer. Developer specifics change even though the theory doesn’t.
Ingredients change because of commercial or social reasons– lumped together as business. Sold as progress. Chemical photography has realized greater changes in the emulsion making, that being at the industrial control level — that level being as that of the end of the 20th Century. It got so far, but not further.
D-72 is Dektol.
Paper developers are very active developers. Paper is less sensitive to light than film. The latent image needs a stronger developer to make it visible. (halides to silver)
[read the cards]
| Developing Agent | D-72 (paper developer) | D-76 (film developer) |
|---|---|---|
| Elon (metol) developing agent | 3.0 grams | 2.0 grams |
| Hydroquinone | 12.0 grams | 5.0 grams |
Not knowing what the brand name means, means not knowing.
the time of expanding meanings. longer times. industrial chemistry. big mechanical things. roads. trips. group darkrooms.
transition decade. continued the 60s. expanded it. extended it up to the edges of the 80s. the last time to be, to become liberal.
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