The interesting part of this challenge is that many diagonal lines are also leading lines. Since we’ve already ‘done’ leading lines, I’ve tried to come up with some images that are all about the diagonal itself, rather than them being, even incidentally, leading lines too.

I think this is my favourite of this week’s selection:

The mast of a catamaran

And here are a couple of others:

The UAE Airforce display team celebrating a national holiday in Abu Dhabi

Snowmelt draining into a culvert close to Tranquility Base

And here are a couple of what Cee described as ‘implied diagonals’:

Bigger than your average bubble

A mother and child moment between two giraffes on Sir Bani Yas Island

Finally, my favourite images from earlier contributions to this thread. The first from the Vertical Lines challenge and the one on the right from Leading Lines (which, neatly enough, is also an implied diagonal):

Looking up inside an open lift, itself inside a roofless bell-tower in Sarlat

Cee’s Compose Yourself Photo Challenge: Diagonal Lines