I was recently at a Mark Smith workshop, and I was talking to him and his son about tracking birds in flight and finding the subject in the frame at long focal lengths. Up until this point, I had always shot with one eye closed. They suggested I try both eyes open, and it seemed to help a lot, especially with hand-(lens)-eye coordination at 600mm. So, I wanted to ask if people have thoughts on this. Does everyone shoot with both eyes open? This is wildlife/bird focused. I imagine that for landscapes, it could be detrimental.