Couple More Flash Pics - 19 Feb 2017

I took a few more pics this morning using [TTL][FP] and Aperture-Priority on the Nikon SB-900 / D500. Both the Tufted Titmouse and Black-capped Chickadee were exposed 1/350 sec at ISO 640 at f/5.6.  So, this appears to confirm my suspicion; if I want to shoot at least 1/1000 sec using Aperture-Priority then I need to bump ISO to high enough level to REQUIRE 1/1000 sec.