There should be a club for all of us who have struggled getting photos level at Manchester
. Part of the problem is that what looks like level when you are there is often not 'level' according to the screeners. I have learned that when there is any doubt with the result that you get on the computer screen, you need to make it look level.
For example, I think there is no reliable reference in the first shot for you to use at all. But, given that there is a slight impression of CW
rotation needed, I would use the back edge of the taxiway just behind the one that the Airbus is taxiing on - so that looks horizontal. The same would apply to the nose shot of the Balkan.
For the third shot, of the TU154, I would draw a line from the left edge of that 'grass' horizon to the right edge, just beyond the wind sock. Even though you may argue that 'horizon' is not perpendicular to you, I think if that were level the chances would be better of creating the 'impression' that the photo is level. That might also cause the pole of the wind sock to look vertical, though I understand where you are coming from regarding verticals at the edges of the frame.
In number 4 you definitely need the verticals of the control tower to be absolutely vertical - this one isn't far out, but maybe a little.
With 5, as with number 2, you need to make the horizon look level - that's the bit under the Dash-8 on the far left with the horizon on the far right. I think this one needs closer to 2 degrees of CW
Also, to my eye Derek, they all need an extra 'oomph' of sharpening too.
I hope this is of some help.
Enjoy your New Year - all the best.