Carryfast:
Franglais:
I was going to leave this alone, but…@CF
Go to the first post. Look at the picture.
Get a ruler, or your thumb, or anything, and measure the width of the trailer.
99.9% sure that is 2.55m or 8ft 4ins.Now apply your ruler/thumb/thingy to the height of the trailer, ground to roof.
What conclusions would you draw from that comparison?
You can’t get a width v height measurement from the pic because of the angle of the camera v the trailer distorting the perspective.
But it’s a reasonable bet that the width of the max arch height lines on the bridge are less than 3m wide.
The height of the trailer looks less than 1.5x that.
So nothing there which wouldn’t fit the scenario of a >14’ high trailer hitting a 4.2m clearance bridge.
Firstly you`re still talking imperial and metric in the same sentence, seems foolish to me.
If you know your vehicle ht in metric, obey the metric signage. If you know your vehicle ht in imperial, obey the imperial signage.
Scondly, to my eye it is nearer 2 x 3m than 1.5 x 3m, but we`ll ignore that.
Third point.
Does the bridge cross the road at 90deg?
No, so the perspective distortion you mention is relevant here, indeed a quick look at the roof will show that the bridge is offset more than the trailer is. But you ignore that.
What error is there due to the camera not being at 90deg to the trailer?
We do need lots of guestimates for that.
Or get out there and do it…
Looks to me…(not a good start, Ill admit)....that the camera is about 3 car lengths from the trailer? 15-ish m? And the camera is in the road. Road width about-ish 7.5m, its 1m from kerb?
So the observer`s point of view is about 2.75m from c/l of trailer (so about 1.5m off side of trailer?)
Or a scale drawing on the back of a ■■■ packet?