Posted: 15/06/2016 at 19:05
Doesn't look like blight to me but could be one of the other fungal leaf spots or thrip damage. Have a look under the leaves to see if you can see any:
If no creatures, make sure you only water the roots, never get water on the leaves and try and improve air circulation if you can. One way of doing that is moving the plants further apart so the leaves from adjacent plants never touch.