The National Defence University in Finland has published a set of DVDs containing great raw film footage on the Finnish Air Force shot between 1941 and 1944. The name of the set is
Jatkosota ilmassa. There's also some footage on Gefechtsverband Kuhlmey. The DVDs mostly contain material that was shot on ground, but also some shot during actual combat sorties. I have posted
some screenshots of the films on a thread at a Finnish forum. Unfortunately there's no news if the set can be bought. It's currently available only at the University's library at Helsinki.