It's a very tricky manoeuvre
the two shots were engineered to be as vertically aligned as I could get them,
not easy on a breezy day, as you can see there is a large overlap, this is helpful, as it gives more scope for manipulation, and alignment.
start a new page in photoshop and open both shots,
Drag n drop both shots as individual layers onto the new page
Aline the shots one above the other to roughly where they should join up,
they are way out of perspective to each other
just play with the distort tool until you get a match all along the seam,
flatten the layers, then you have to crop the final pic to get rid of the distorted edges,
Items needed
1 x Nokia N70
1 x Cathedral with no distance to take a full sized shot
Adobe Photoshop
A Bl***y lot of time
A awful lot of Patience
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