Since HC110 is still available why would anyone care? Plus based on the
available evidence there's a distinct possibility that the Broccoli
didn't even contribute to the development.
On 11/16/2011 8:21 AM, Collin Brendemuehl wrote:
Here's something quite novel from APUG/Alan Johnson.Developer from Broccoli
Many plant chemicals contain phenolic groups (as do
hydroquinone,pyrogallol,pyrocatechol).I tried to extract the phenols from
Broccoli by heating 200g Broccoli in 1% sodium carbonate (anh) solution at 100C
for 15min with stirring.After filtering this Broccoli extract I added some
Phenidone dissolved in isopropyl alcohol.
PP-1 developer:
Extract of 200g Broccoli
Phenidone .................0.1g
Sodium Carbonate 1% to 600ml.
I checked that phenidone alone was not doing the developing by developing
old APX 400 30m 20C ag 10s/min in PP-1 without the Broccoli extract.The
negatives were very thin and flat.
For the test, APX 400 at EI=200 was developed in PP-1 30m 20C ag10s/min.
The negatives were slightly underdeveloped but otherwise good.The
attachments show the full negative and a 0.2in square section.
To see if there was any tanning I bleached the negs in 100g/L
ferricyanide/bromide and fixed them.No relief image or tanning could be seen.
This surprised me as I expected plant phenols to be like
hydroquinone,pyrogallol, pyrocatechol and tan the negatives.The only
explanation I can find is that the oxidation products of Broccoli phenols are
not very stable and do not spread through the gelatin (Photographic Processing
Chemistry, LFA Mason 1975 p172).Of course all this does rely on the assumption
that it is the phenols from Broccoli that are involved in the developing.
Sincerely,
Collin Brendemuehl
"He is no fool who gives what he cannot keep to gain what he cannot lose"
-- Jim Elliott
--
Don't lose heart! They might want to cut it out, and they'll want to avoid a
lengthily search.
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