Just wanted to share some perspective.... Your experience may be different but...I wanted to put this in the mix. I have 16 cameras watching the outside of my home. Most are high megapixel 4k cameras with IR night vision and all have motion sensing capabilities, including zone definition, sensitivity adjustments, etc. I have explored useful motion detection with these extensively. My experience is that motion detection on cameras is not reliable. I have found that, especially in summer (bug season), too many false detections occur to rely on them for motion. Wind blowing grass, bushes, shadows, etc are other considerations. If you have ever seen what a bug looks like on video flying on IR night vision, it paints a wild white streak that looks like an alien just flew by.
While in principle motion detection from cameras sounds good on paper, the real life experience is very different. Might I suggest that you look into outdoor Z-Wave or Zigbee motion detectors that are much more accurate in detecting motion and much more reliable. As I said your experience may be different, I just wanted to give you some food for thought before you invest heavily in cameras for motion detection.
