Perseid fireball afterglow
Revisiting Perseid images, I found that the camera had also caught the skyglow after the fireball, saw it visually at time but didn't think to check camera. The sky glow is caused by the glow form the atmospheric gases heated and ionised by the meteors passage.
Have tried to keep views same as for fireball.
The skyglow is visible on 3 images after fireball, ie 75 secs , so persisted for at least a minute after the fireball passed, gives an indication of how much energy was released, the spreading of the glow shows the movement of the upper atmosphere, also seen on radar echoes.
All the images of the Perseid shower were taken on the evening of the 12/13 Aug. the fireball image was timed at 00:21:37 (13/08/15) and the afterglow 00:21:52 (13/08/15).