On mine, I use a small auto flash (Nikon SB-9 - GN14/45), and just close the aperture a stop or so from the what's recommended on the flash. The GSN takes care of the ambient.
The RF's: Yashica GSN & GX; Oly 35 RC & DC (my Avatar); Mamiya 135 EE; Dad's Argus C3; a Canon 110ED 20 and a Kodak Pocket Instamatic 60...
Plus: Nikon F/FTn, FM & FE2; a beater RB67 in need of a bellows & some TLC; a pretty little Zeiss Ikon Box-Tengor 56/2; some other Kodak first generation 110's; a couple of Weathermatics...
...And having a blast playing with all of them!
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