In the July Newsletter you will see that Ron Croad - our hard-working Secretary - publishes revised quantities of our E6
formula required to fill the new range of Paterson developing tanks that he has recently purchased. Just as a reminder, the
pH's and processing times are also given.
You may have noticed that Ron has made slight changes to the standing pH values for the 1st and Colour developers. These
changes are slight - down to two points to 9.7 for the 1st Dev: down one point for the Colour Developer. Following carefully
these amended pH values, together with more care at the reversal stage - has produced my most satisfactory batch of slides
from a 'mixed bag' of six films than ever before: I would go so far to say that these are the most consistent films as regards, lack
of cast, cleanliness, true colour rendering etc, that I have processed to date.
From this 'mixed bag' I was particularly anxious to view the slides of the latest 'super film' from Fuji: 'Velvia'. I shall have more to
say about this film on another occasion, but I will add add that I consider it to be absolutely supurb and, for me, it fulfilled all
the claims made for it by the photographic media. 'Ektachrome H.C100' was another one in the 'same pot': excellent results from
this too. 'Tura' is a name previously unknown to me; Ron Asked me to try out a roll of 'Turachrome 200': this: in spite of the
higher speed and larger grain structure — is an excellent film and I would be happy to use it whenever I need something faster
than the usual 100 ASA that seems to be the standard these days.
It has always been my practice to store my films in the deep -freezer. The oldest for this 'mixed bag' was a roll of CRX100 Barfen.
This actual film is of Fuji origin, so it must be at least eight years old! It has processed perfectly and is indistinguishable from
another roll of standard Fuji 100 that I put through the same 'brew'. The last of the six was Konica. This film was from one of
their recent batches and - already spoken at length about my confidence in Konica's products - the slides were 'spot on'.
Now, if we are honest with ourselves, we would not have had many processing sessions - when we've put through six films (all
of different makes and ages!) that we expect to be free of some sort of cast (be it ever so slight!)..., would we? Hand on my
heart, I can say that this is my first experience of a completely trouble - free run with this number of films in the same brew ......
and I am unanimous in this!
For quite a while now, Ron and I have discussed - to the point Of complete agreement - the recurring question regarding the
amount of the reversal bath that needs to be 'carried over' in to the Colour Developer. After all, its largely a matter of subjective
interpretation when we read from Kodak's Data Sheet No. 119Z use no wash between the Reversal Bath and the Colour
developer.
What is perhaps not generally known, is that for the most part these instructions are intended for the operatives of line
processors whose only concern Is the amount of liquid that is actually in the film emulsion at the moment of change-over.
When the film leaves the Reversal Bath the surplus is removed by either high-pressure air-jets; or physically so, by powerful
'squeegee' rollers. Therefore the message is obvious: the amount of 'carry-over' - vital though it is - is small and the only way
we can emulate this part of the process, is for us to remove all the surplus Reversal Bath fluid by washing the tank and its lid
very thoroughly., and (here I exceed the original instructions to 'shake' the spiral') wash the film in its
spiral, sparingly but sufficient to ensure that the carry-over' is what remains in the emulsion.
Many members have - without any scientific knowledge to back their suspicions - said that such problems that they have
experienced from time to time, are , as they think " to do with the Reversal bath". In the light of my own experience, they may
well be right.
It would be to our mutual benif it to hear - through the medium of the Newsletter - just what are your views upon this most
important and contentious aspect of our hobby?