Yet another ‘lost’ developer I’ve been playing around with.
I’ve no idea how old this pack of Neofin Doku is, I got it in the same batch of material as the Neofin Red and Blue mentioned previously. It’s no longer available (to the best of my knowledge) and was originally produced for processing ‘document films’ (high contrast, very slow and extremely fine grained) to a very low contrast to enable their use for conventional photography. As such, it was one of the standard developers for pictorial use of Kodak Technical Pan 2415, a remarkable film that I used quite a bit when it was still available.
Another use was in the processing of b/w internegatives from colour slides to enable black and white prints to be made, where its inherent low contrast enabled the reproduction of the wide tonal range of a colour slide.
Here is the rather florid verbatim English description (no doubt translated from the original German) in the very brief instruction manual:
Field of Application/Method of Operation
Single developer for document films in picture quality photography.
Neofin doku works extraordinarily softly, has a high sensitivity utilisation and therefore makes it possible to use some document films for picture quality photography.
As a result of this, extremely sharp negatives can be enlarged with almost no limitation.
Due to the fact that negatives are harmonically graduated, enlargements can be produced on papers graded ‘normal’ and ‘special’.†
A further application is the production of b/w internegatives for b/w paper pictures (photos) from transparencies (slides, diapositives).
Handling of higher contrasts when switching to harmonically graduated b/w negative is possible through using Neofin doku with it’s (sic) ultra soft development.
†A reference to papers like Agfa Record Rapid, which was produced in a Grade ‘Special’, somewhere between Grade 2 and 3 (an excellent paper btw).
The development guide chart in the pack only gives a processing time for one film, Kodak Technical Pan. The booklet however mentions both this and Agfaortho 25, giving times for both.
Kodak Technical Pan was not assigned an ISO rating (or in those days, an ASA rating) but was commonly supposed to be around 6 ISO for its intended use (i.e. not pictorial). The Doku instructions recommend a speed of 50-100 ISO for Technical Pan. Unfortunately, I have no Technical Pan left to test this. All my experience with that film was using Kodak Technidol developer and I remember getting very variable results, it was a tricky film to use.
So, given that I don’t have Tech Pan, what would this developer be like with a normal but contrasty film like Pan F+? The booklet suggests the use of three films for making internegatives – Agfa APX 25, Agfa APX 100 and Ilford Pan F, and gives times for each. So I processed the notoriously contrasty Pan F (rated at 50 ISO) for the recommended 6 mins in Doku, initial agitation for 1 minute and then 5 seconds every 30 seconds, at 20°C.
I shot one roll on my Fuji GW690 of the gladioli vase, using different exposures and apertures. All will be printable.
The marked frame was the one selected for scanning and processing, reproduced at the top of this page. 1/8th second at f22. When I get to print the negative on real paper I’ll be aiming for a similar result! (I’ll post it here.)