I have some phenidone here to play with also - have been meaning to try a POTA developer for a while now, but haven't had a shoot I can experiment with and compare the results easily (telecine of 16mm).

Maybe I will try some 120 in it.

Thanks for the info Ian - I'll look into those developers.

D19 is often specified as an 'aerial/scientific' film developer...

What were 'aerial films' exactly ? I'm guessing they used them for aerial photography (?) but more to the point what were the characteristics that required D19/ID-19 etc... ?

With 24deg (its hot upstairs here) standard solution I'm getting good Pt/Pd negs in 20mins tray dev near on constant agitation with Bergger BPF200 btw ...