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Brilliance in black & white
for you
DiXactol™ supplementary
notes on processing
(3 Pages)
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On the DiXactol™ instruction sheet some
people may tend to skip over the 'Caution' subheading thinking
that it just gives the usual safety warnings about photographic
chemicals. Those warnings are shown, of course, and we should
observe them carefully. However, there is also a warning about
negative unevenness which is also important, and may be overlooked.
The vast majority of DiXactol™ users have no problems whatsoever,
but if you do, here is some troubleshooting information.
Do not be perturbed if either of the two solutions looks slightly
cloudy. Both are virtually saturated solutions, and this appearance
is normal and will not detract from development effectiveness.
It is a fact that any tanning and staining developer
is sensitive to factors that tend to cause unevenness during
development. DiXactol™ is too, especially in its two bath
form. The benefits of the developer are well worth any extra
care that may be needed.
The key issues causing such unevenness are contamination of
reels and tanks, and the quality of the local water supply.
If one or both of these is a problem, no amount of agitation
modification will cure it. Some people encountering unevenness
have been tempted to greatly increase the agitation. This does
not work, and indeed gives much greater density at the edges
of the film than the centre.
In the case of contamination, reels and tanks may appear to
be scrupulously clean, and thorough rinsing has always been
given after use previously in other developers and processing
solutions, yet the first time DiXactol™ is used, there
may be marks at the edges of the film where they are held in
the spiral. The good news is that the use of DiXactol™
once seems to clear this problem for each reel concerned in
many cases. Single bath development is much less prone to
this problem - see below.
Water quality is a separate problem. The characteristics of
water vary infinitely in different geographical areas, and
they vary in the same area from time to time. It is not enough,
for instance, that water is soft from the tap. It may well,
for instance, be slightly acid as well, which inhibits the development
and the tanning and staining action. Nor is filtering which
removes solids necessarily an answer. Traces of non-solid materials
in the solution may well also be present. The possible variables
are just so great that it is impossible to predict. Use of purified
(deionised) water available from all pharmacists economically
or distilled water to mix the developer working solution (not
the other processing solutions or wash) usually solves this.
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