Nobody in the orchestra is looking at Lennie!

I guess that he is doing his "thing" for the people singing in the chorus, but I find it amusing that nobody in the orchestra is looking at Leonard Bernstein. The presence of two harps and the two female soloists tells me that this is Mahler's Second Symphony, the sky and the white orchestral attire tell me that this was a Sunday afternoon concert at Tanglewood, and a quick search of the Boston Symphony Archives tells me that the year was 1970. I can name every one of the musicians playing, even from behind.