From "The Diary of Winter Sonata" by PD Yun Seok-ho (2005)
... Shooting JS's solo cut also required a long time. The issue was - how much should BYJ's face be covered by the book? BYJ is the type who cannot get into his acting until he can fully accept the situation he is playing, and to have him understand the necessity of the scene I gave my explanation. Of course I could see his point too, but I had my idea as well. We came to an agreement after talking it over, and resumed shooting.
The shooting of the high school scenes are indeed difficult.
Grow up fast everyone- please!