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Autophen and the
Ilford PQ variants of ID-11 (D76)
Most of the MQ variations of D76 are published widely, but less is
known about the PQ variants of Ilford's equivalent developer ID-11.
Although J.D. Kendall of Ilford discovered and patented Phenidone
(1-Phenyl-3-Pyrazolidone) in 1941 it was 11 years before the first
packaged products containing it went on sale.
Many of these first developers were simply Phenidone based versions
of MQ developers, typical examples are ID-20 PQ and ID-36 PQ, and
research into other possible developer combinations & formulae
continued.
In 1954 Ilford published their first formulae in The British Journal
of Photography stating "As Phenidone is now generally available in
bulk packin g ranging from ¼-oz. to 4-lb., it is felt that the publication
of a number of formulae in which this new developing agent is used
in combination with hydroquinone will be useful to those workers who
wish to compound their own developers".
These developers were:
ID-62 - a PQ variant of ID-20
A very similar developer for Contact prints - (identical except the
Potassium Bromide is cut to 0.25g/litre)
ID-67 - a PQ variant of ID-2
Fine Grain Developer for plates and films - a PQ
variant of ID-11 - the formula below.
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Fine Grain
Developer for plates and films (1954)
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| Sodium sulphite (anhydrous) |
100 g |
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| Hydroquinone |
5 g |
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| Borax |
2 g |
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| Boric acid |
1 g |
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| Potassium bromide |
1 g |
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| Phenidone |
0.2 g |
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| Water to make |
1 litre |
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Development time: 7-11 minutes at
20° C.This developer has characteristics approximating to
those of Ilford ID-II, but shows less change in activity during
use.
This PQ version of ID-11 was taken further by A.J. Axford
& J.D. Kendall who published a version with slightly different
buffering for commercial processing, and they included two
types of replenisher. |
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Axford-Kendall
Phenidone-Hydroquinone Fine Grain Developer
"Autophen"
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Working Solution |
Replenisher
Topping up method
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Replenisher
Bleed method |
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| Water (50°C0 750ml |
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| Sodium sulphite (anhydrous)
|
100 g. |
100 g |
100 g |
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| Hydroquinone |
5 g |
8 g |
6.25 g
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Borax |
3 g |
9 g |
4 g
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Boric acid |
3.5 g |
1 g |
2.5 g
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Potassium bromide |
1 g |
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| Phenidone |
0.2 g |
0.24 g |
0.22 g
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Water to make |
1 litre |
1 litre |
1 litre
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| pH |
8.95 |
9.28 |
9.09 |
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| Development time |
10mins at 20° C |
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| Autophen was commercially available in both powder and liquid form. |
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ID-68 was a reformulation
of the Fine Grain PQ developer to give better film speed and
is similar to Microphen, in Ilford's words "Phenidone as used
in the formula below gives remarkably high emulsion speed
with fine grain (approximately to ID-11 standards) with development
times of 10-15 minutes at 68° F.
This developer shows exceptionally small change of activity
with use." Also "Development times as for Microphen" |
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ID-68 Ilford
Phenidone-Hydroquinone Fine Grain Developer
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Working Solution |
Replenisher |
| Sodium sulphite (anhydrous) |
85 g |
85 g |
| Hydroquinone |
5 g |
8 g |
| Borax |
7 g |
10 g |
| Boric acid |
2 g |
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| Phenidone |
0.13 g |
0.22 |
| Potassium bromide |
1 g |
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| Water to make |
1 litre |
1 litre |
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| This developer may be used undiluted. |
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| "Development times as for Microphen" |
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A comparison
of ID-11 (D76) and the Ilford PQ Fine grain developers. |
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ID-11
(D76) |
Ilford 1954 |
Axford/Kendall |
ID68 |
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MQ |
FG PQ |
PQ |
PQ |
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| Sodium sulphite (anhydrous) |
100 g |
100 g |
100 g |
85 g |
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| Hydroquinone |
5 g |
5 g |
5 g |
5 g |
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| Borax |
2 g |
2 g |
3 g |
7 g |
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| Boric acid |
|
1 g |
3.5 g |
2 g |
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| Phenidone |
2 g (Metol) |
0.2 g |
0.2 g |
0.13 g |
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| Potassium bromide |
|
1 g |
1 g |
1 g |
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| Water to make |
1 litre |
1 litre |
1 litre |
1 litre |
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| Axford & Kendall's Commercial
"PQ Fine Grain Developer" formula has been incorrectly described
as being of "Microphen type" in books like the Photo Lab Index and websites like
Silvergrain, it is just a differently buffered version of
the PQ ID-11 type developer Ilford published in 1954.
"The great tolerance to variations in bromide concentration of a Phenidone-hydroquinone low pH developer reported by Axford and Kendall decreases at the working pH of general purpose negative developers of the usual M .Q. type used by photofinishers, and therefore in formulating a Phenidone containing developer for long life in photofinishing establishments the pH has been kept down in order to take the fullest advantage of this important property."
"The developer worked out to produce negatives of the type required by photofinishers and to have a long, even indefinite, life is marketed by Ilford Limited under the name- “Autophen”."
B.J., 1957, June 14, p. 342.
Ian Grant © 2008-2017 |
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