I am not sure of those in ASK Brown are real originals of the Döpler series or superb copies - or variations, some of them are not from the missing first volume which gives us the opportunits to compare with the existing plates.
This is evident for the Horse artillery plate, the original shows a far more elaborate back ground, whith mounted gunner in the idstance and landscape - while the ASK Brown plates does only show the gun and the officer and gunner.
I hope Friese is also discussing those deviation - looking forward to your re-view.
A pity that the first volume is missing - some of the most interesting units are re presented there - and whoever did see the plates will acknowledge the staggering amount of very fine detail.
Maybe the first volume rests with a private collector who doesn't have the same altruistic attitude as the ASK Brown collection