ADOX CHM Professional films

s-12 · 2006-08-21T07:03:29+00:00

Hallo, auf der ADOX Seite habe ich gelesen, dass die Filme aus England stammen. Zudem tauchte dieser Satz auf "Diese Filme können in beinahe jedem Labor zur...

s-12

Hello, I read on the ADOX website that the films come from England. It also said: "These films can be sent for development at almost any lab, as the development data is identical to that of the FP4 and HP5." Can we assume that this is the same material as the Ilford films? Best regards

Tammo

Yes, you can :D

gr00vemaster

Yes, you can :D

Well, there’s just one thing that puzzles me: I always develop the CHM125 PRO with Mäßig Tanol Speed. The recommended development time for that is 7:30 mins, whereas for Ilford FP4 it’s 9:30 mins. How does that come about? There must be differences after all... But otherwise I’m very happy with the CHM range from ADOX, both the 125 and the 400!

MirkoBoeddecker

Ilford is experiencing the same issues with its non-T-Crystal films as we are. Due to the new gelatins, the films build up density and contrast more slowly, as all gelatins still available on the global market are now optimised solely for T-Crystal emulsions. The CHM emulsions we sell date back to the Ilford bankruptcy and were still cast using old gelatins. Consequently, the CHM builds up density and contrast more quickly than newer FP4. This is comparable to the development problems with the CHS 50 (see the long thread where we get a telling-off). Unfortunately, it took over a year for us to identify this as the cause of the issues with our films, because artificial ageing did not replicate this effect. The differences between CHM 125 and FP 4 are purely due to variations in the emulsion, just as with the ADOX CHS. Best regards, Mirko

s-12

Am I getting this right? The CHM 125 is comparable to the old FP4, and gr00vemaster’s mention of a time difference is referring to the FP4 Plus? If I take that a step further, the FP4 Plus can no longer be developed using the times and other settings from the FP4 – sorry, I haven’t seen any up-to-date tables in ages. Regards

MirkoBoeddecker

No, the CHM is already rated ‘plus’, but even with Ilford, no two batches of emulsion are exactly the same. Wolfgang therefore compared a brand-new roll of FP4+ with a slightly older roll of CHM 125 = FP4+ and noticed this difference in processing time. These tolerances are simply unavoidable these days. You need to test emulsions and vary them slightly if you want perfect development results. That’s why most manufacturers specify time ranges rather than exact times. But it’s not that big a deal. Only those who work with absolute precision and have all other parameters completely under control will notice such differences. Normally, all parameters fluctuate by plus or minus 20%, and usually one factor compensates for another. The analogue process also has plenty of leeway. Best regards, Mirko