Thanks dalth500. Well, I knew from my D700 years, that 6400 "could" be used in similar situations - only the D800E behaves like one stop better, (12800) and often I dont do any NR with the D800E at all, even this high. Above do have some NR to it in LR, as its a 2900x4400 crop. Somehow the "APO" tag on Zeiss & Leica seems to me to reduce noise relatively to other fine lenses, when really low on light... /Peter René