Several members have expressed interest
for some time in the idea of one-shot slide processing to achieve, economy
plus consistency. Well, it can certainly be done using just 100 ml. of
each developer with 20 exposure films and I consider it very probable that
10 ml could cope with a few more frames.
A test was made recently with a 20
exposure Barfen CRX100 film wound onto the, outer spirals of a Paterson 35
tank. Some tanks for a single 35mm film need only 250 ml of solutions for
normal processing with inversion or twirling agitation but the Paterson
requires 290 ml of solutions0 In this test only 100 ml of First
and Colour Developers were used. It is not practicable to check the
solution temperature during the process so a fixed routine must be
adopted. I gave the tank two presoaks of 30 secs. at 40C, poured in
solutions at 39C and rotated the-tank on it’s side in a bath maintained
at 39-40C giving approx 20 rpm. It is essential to rotate the tank in the
direction, which drives the solution around the spirals. Development was
at the times as used for normal processing. The usual 290ml plus was used
for the other baths with the tank upright. I checked the developer
temperatures after use and found the FD at exactly 38C and the CD at
38’5C.
This was a pretty interesting test as I
didn’t use fresh solutions but in each case took 100 ml from litre
bottles of developer made up 6 weeks earlier and already used to develop 5
films. And the results? All 20 frames fully developed with colour and
density exactly the same as the previous 5 films. So there is no reason
why a litre of FD and CD should not be used on a one-shot basis to process
ten 20 exposure films. I intend trying this process with a longer film
later on. It is recommended that any members trying this should ‘make
sure that the subject matter is repeatable and that five frames should be
an exposure/development test with shots of articles of varying colours at
half stops from one under to one over.