Hi again Tom,
Back when your DW was on the telly, ( a time when I lived behind the sofa ), we only had a black and white set. We didn't get colour until 1980, so most of what we saw was a grey TARDIS, a stripey grey scarf and grey monsters e.t.c. Not to mention grey assistants.
Filming at that time, were there any considerations towards non colour viewers knowing that many of us weren't seeing the full picture, if you see what I mean ?