The developer toolkit consists of several developer concentrates, VGT A, B, C with which you can mix your own magic brews. With VGT, you determine the image tone, from soft to hard with an one or two-bath process.
The developer solutions can be mixed in any combination that you feel like trying – experimenter's paradise! Here are the basic effects of the different solutions
VGT A – a hard-working but very slow developer which is of great benefit with the 2 bath systems as the shadows have time to differentiate and become richer.
VGT B – soft-working developer giving a neutral to cool image tone, the image building quite quickly.
VGT C – this activator is added in the same quantity as the sum of VGT A and VGT B developers. Larger amounts cause the developers to work faster, softer and with a cooler image tone.
Finisher Blue – add this to the working solution combination A/B/C to get a cooler image tone, keep on adding until the required cold tone is achieved. Usually only 5-10ml is enough.
Add about 50ml developer (A+B,) to 1 litre of water and add 50ml of activator. You can use smaller amounts but then the development time will need to be increased.
A+C+Water results in a slow developer which alone cannot build the full tonal range so a second bath with a soft-working developer is necessary). Add, however, about 5ml of VGT B to the A solution and a super additivity is created which makes the developer work faster and stronger.
Note that the image tone is mainly determined by the paper emulsion. Very cold tone emulsions can be developed into neutral tones. Warm tone papers, on the other hand, react much stronger.
Very thin, flat negatives can be saved with the 2 bath process