It looks more like H. alcyone/genava to me. The postdiscal band has a pretty sharp angle on the hindwing-underside and a somewhat sharp (although admittedly not very pronounced) bend on the upperside. It also looks quite small, but without reference, I can't really tell. If you want to know for sure, you'd have to look at some rod-shaped scales at the tip of the abdomen (see here for H. fagi).
Also, the taxonomy for these three species (H. fagi, H. alcyone, H. genava) is quite uncertain at the moment but if determination is done with the method I mentioned, I suppose you can call it whatever the taxonomists will eventually agree on calling it