A perfect passing picture at Piddington on 17 September 2017. 168001 heads south with the 1H35 13:12 Birmingham Snow Hill to Marylebone Chiltern Railways service, passing 165035 with the 1G35 13:36 Marylebone to Birmingham Snow Hill. Despite firing off a fast sequence of shots, I thought at first that I hadn't quite got this precisely right. I wanted the two trains to be exactly opposite. However, I realise that if that had been the case, because of the side lighting, the front of 165035 would have cast a shadow on the left edge 168001's front end, so this in fact the ideal position!