A CRT pre-production unit was established at the Laboratories, led by R. Harvey who pre-war had been engaged on work in the Heat Laboratory, to produce quantities of tubes to Wembley design. In addition the Ministry of Aircraft Production set up a shadow factory at Shaw, Manchester, managed by GEC, at which production of CRTs was led by D.P. McKeon, supported by K. Middleditch and Miss K. Ball (who by this time had become Mrs D.P. McKeon), all of whom transferred from Wembley. In spare moments towards the end of the war, senior members of the pre-war Television Group and the CRT Group turned their thoughts to the introduction of post-war television, particularly to the question of higher definition and colour. There were differing views: G.C. Marris favoured consolidation on the pre-war standard, at least for a period: D.C. Espley favoured going to an 800-line black-and-white system, while L.C. Jesty developed what was to be, in the future, his considerable interest in colour television.