Just to add to the argument abot size vs distance, we have below a photo of two LNER van chassis, the near one is 4mm very close and the rear one is 7mm very far away. This of course is complete nonsense, the near one is 7mm awaiting its new owner, the rear one is a Bachmann one to which a number of brass etchings have been attached in an attempt to see if I can still 'do' 4mm scale.