Thanks Franek for this info, it suites my further research. And like used, part of the answers were just under my nose. In the same Modeller's Eye I found the pictures I was looking for: just the same, but uncropped as those in the JaPo book (both references mentionned in my previous input).
Strange however: the WNr mentionned in the Modelle's Eye book is 210185.
In the WNr list of JaPo's volume 1, both planes are mentionned to be part of the Soviet AF Scientific Research Institute (see also
http://www.airpages.ru/cgi-bin/epg.p...40&page=fw190d)
This leaves me with another problem: I have now 3 WNrs possible for those pictures: WNr. 211251 - the most improbable
WNr. 210251 and WNr. 210185.
Is there someone who can clarify this situation???