I try to spend time with the horses before and during an event so they become accustom to me and the gear. Horses like people may react negatively to clicking sounds from a strange creature with one big camera lens eye. However even with loads of time there is no guarantee that a horse will ignore me.
This is my wife's horse Miss O and she has spent more time infront of my camera than any other. She sees me at home, in the barn and on the trail. She has even carried my big rear around a time or two so it's safe to say she knows me. However she is also an alpha mare and very aware of her surroundings. So why this reaction when they they arrive at an observation? I'm across a creek on the oposite bank sitting under a tree. At this point we are about the same height so I'm not in a superior position. In fact when all the riders went down into the creek I stopped shooting to avoid evoking a flight reaction. She was clearly not afraid as the next images in the set are normal.
Perhaps this is just a 'tag you're it' or "I see you" look but I don't think so. I'm left with the lingering thought that a horse told me something to the effect "I know who you are, behave yourself because I know where you sleep!" It worked, I did. Pavlov would be amazed.
See y'all on the trail.