Tetenal NEOFIN BLAU Film Developer is a one-shot developer for b/w negatives with the highest resolution and exceptional sharpness. The film’s speed is fully exploited. Ideal for slow/ medium speed films. Neofin Blue negatives are characterized by a high acutance and a detailed shadow reproduction. The formula is designed for the processing in developer drums, e.g. such as Jobo or Paterson. Dispose of the used working solution after processing, due to exhaustion.
NEOFIN BLAU comes in a box with 6 x 50 ml bottles for mixing 300–700ml of working solution from each bottle.
The concentrate can be mixed 250 ml water + 50 ml concentrate or 450 ml water + 50 ml concentrate or 650 ml water + 50 ml concentrate. The choice for a certain dilution depends upon the size of the developer drum and the chosen developing time. A basic rule is: higher dilution = longer time and vice versa. Most common dilutions are to 300 ml and to 500 ml, while a dilution to 700 ml is possible only with selected films such as Rollei Retro 80 S, RPX 25, Ortho 25, Superpan 200 and Foma 100, which require a developing time of not more than 10 minutes for the 500 ml dilution. The developing times for the 700 ml dilution result from multiplying the times for the 500 ml dilution by factor 1.5 (guide value).
Originally packed concentrate has as shelf life of approximately 2 years. Fresh working solution has to be used shortly after mixing.
Developing is at room temperature, generally at 20 °C. You can adapt the developing time, if higher or lower temperatures are used. Depending on the film used and the chosen dilution the factor of the reduction or the extension of the developing time differs: the rule of thumb is factor 1.2 at 18°C, factor 0.85 at 22 °C and factor 0.75 at 24°C.
The attached table shows the development times for current standard films, each for the different dilutions. The indicated developing times have been determined to achieve a beta of approximately 0.65, they are to be understood as starting points that can individually be decreased or increased, depending upon the desired results.
Agitate the developer drum continuously for the first 30 seconds, afterwards agitate (tip over) once every 30 seconds. Processing in rotary tube processors is not recommended.