Akira, this would indeed be the case for the 300/2.8. The 300/4 PF would not yield enough subject isolation. Dark bricks with white joints are difficult to get rid of. The colour version has better "contrast", but is less suitable for the subject.
For the present session, the shots at f/2.8 work better, given the "presence" of the background. I sometimes chose f/4, because I was overly anxious about the sharpness of the face, given that the subject was moving a lot (the 105/2.5 is sharp enough per se, at least on Df, at all apertures). Well, subject isolation is more important than sharpness here.
Erik, you have a point. The roughness is intentional, although a bit excessive, as a result of significant cropping. Maybe the film emulation (HP5+) was not the best choice.
I have tried to increase the contrast between subject and background using various filters in PP, to no avail. The Zeiss 135/2 wide open would have done a better job here.
Concerning facial expressions, see my above remark - it is one of the reasons for culling. Such expressions are OK in videos because they are transient; once frozen, they would not always "work". #4 and #8 are interesting here, the rest is just acceptable (and when there's a foot in front line #9, they are even better).
