So, at the time the BNOW fledglings are no for a longer period returning to the cavity and it’s vacant for a while - which is what commonly and at some point comes about - I will go up there and set up a new digicam (the a person which is there is Really aged), In the meantime, the cavity is being partially "lit up" by the infrared LED’s from the PTZ cam, so that is why you can nevertheless see a small little bit there at night time.