Class 25 25125 gets a passenger train away from Derby. An unusally uncaptioned slide I suspected that this either the Nottingham to Llandudno SO service or possibly one of the Skegness services. Slide is dated 1976.
A trawel through the excellent http://www.class25.info/ website suggests that this could be either 1D30 the 0735 Nottingham to Llandudno or more likely 1D17 the 1300 Llandudno to Nottingham service on 14/8/76.