At last I'm getting there.

I believe I have solved the puzzle. The sheer numbers of the jackdaws in the morning flights have been very hard to capture. However I found that taking pictures of them flying away from the camera succeded in catching the numbers involved.

I realised that with no roof showing there was no idea of sheer size of the flock. I set up as well giving a lapse in time to start taking the shots as soon as I saw the first birds.

It meant that the first few frames were blank but at 8 shots per second it also caught the coverage and indicated the distance the flock spread to.

Looking at this picture allows the eye to see the amount of sky and space that these birds take up. What distance are the furthest birds from the camera? A quarter mile? A half mile?

And then consider that there are birds flying beyond them too.

The next thing is to get shots from the front of my flat, using the same set-up.
I reckon that taking in the whole flight they could even spread to around a mile and a half. 

Woke late on Thursday morning. Almost six o'clock; by the time I had showered and made my coffee etc. it was too late to set up the gear to catch the birds. 
Roll on Friday ! ! !