Views on the photographic universe by Erwin Puts

Adox HR50

The new Adox HR50 is a remarkable emulsion. It is based on a microfilm, but with additional chemicals to increase the effective sensitivity and enable the use of some standard developers. The famous Crawley formula, FX 39, is one of the options. I used the film with an indicated Iso of 40 and the FX39 in a dilution 1+19 (to compensate for the highlights) for 20 minutes.
The test chart was the grey chart, issued by Sekonic and the exposure meter was indeed the Sekonic L-398-A. Camera was the Leica M-A.
The fog level was very low (density 0.15).
The Zone V was spot on with a net density of 0.80 (official = 0.75). The Zone I (the one designated for the true speed of D = 0.10) was 0.08. Quite close to the norm. The Zones II and II are rather thin with a D of 0.13 and 0.26. The highlights were a bit too dense with VI = 115 and VII = 1.41.
A reduction of the speed to EI = 25 is advisable and a reduction of the development time to 15 minutes is also advisable.
Acutance is high and grain hardly existent. This is a worthy successor of the famous Kodak Tech-Pan.
The graph as made is below. It has the classical S-shape.