I can assure you it is not an optical effect. The 1C definitely had a planform kink and I have seen it, touched it and photographed it. de Havilland/Hawker Siddeley general arrangement drawings showed it (though they were dreadful and misleading in other ways!) I attach a phot of G-ARPO's wing to try to prove my point.
The 1E had a modified wing with slats (instead of leading edge droops) and slight chord increases (from memory, 2 percent inboard and 1 percent outboard). When they fitted the slats and modified the leading edge, theyt dropped the planform kink. So the 1E did not have a kink.
The 2E and 3B had straight leading edges, like the 1E.