The tree was not very big. My camera, however, was quite large (Canon EOS-1D Mark IV), and I managed to get it up in front of my face before she peeked out around the trunk to see if I was still there.
With the camera in front of my face, instead of being confronted by a pair of forward-facing predator eyes pointing right at her, there was just a blank black rectangle making clicking noises.
Curiosity overpowered caution, and the squirrel sidled toward me along a branch as I shuffled slowly forward with my EF 24-105mm f/4L IS zoomed all the way to its limit (136.5mm equivalent on the 1D's APS-H sensor) until I was practically up in her grille.
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