...
with the answer:
for this i really have no idea. 85mm
This answer was the closest guess, and
And here is a setup I took the photo with. It is an old-school manual Revuenon-Special 135 mm 2.8 on Sony Nex-6.
I bought this lens for about $25 in decent condition. I'd never had a lens with this focal lens and was curious what can I do with it. Now I see, that I don't use it too much for the landscape photography as I prefer the wide angle in probably 80% of my shots. But it is helpful to take the photos of my kids without intrusion in their game. The manual focus is tricky though as my kids often are faster than I.
