Actually it was not day one, as I spend a week arranging sensors, flashes and diffusers. It took fair amount of time, because I have to be sure that birds accepted new item in the vicinity of their nest before progressing further. From the project with Coal Tit, I learned, that with high speed photography of flying birds, it’s very important to find the distance at which they are flying past the camera. So I decided to set up the camera from below, to find what will be the focusing distance, when I'll be photographing from the side. On right hand side, you can see both transmitter and receiver and on the left there are two bright spots of firing flashes visible.