I have several episodes of The Judy Garland Show and I totally agree the quality is SUPERB!!!
Of all B&W American shows I've seen to date, that show wins with quality!!! Marconi MKIV cameras are brilliant and were a popular choice for many Aussie TV stations and served well for Aussie television producing superb pictures from say late 50s to 1974 before stations upgraded to colour. Also its predecessor the Marconi MKIII gave pictures pretty much just as superb (both being 4.5" IO cameras) and too was used right to 1974 here in Australia. Both cameras are the workhorse cameras for many networks worldwide during the B&W era, MK4 being more so popular in the Americas than MK3.