How many discussions revolve around what you can see from where? If your evenings in the pub are anything like mine, I know what the answer will be - lots! Some of them are obvious. Of course you can't see Ben Nevis or Snowdon from the top of Scafell Pike. But yes - you can see the Matterhorn from the top of Mont Blanc.
Between these two extremes there is a large grey area. And one of the largest and greyest is in the Irish Sea. Specifically the ever contentious question:
Can you see Llandudno from the Isle of Man?
Summits are easy. They are essentially points. Areas like 'the Isle of Man' and 'Llandudno' are more difficult. What do we mean by the Isle of Man? The highest point? The centre? And where is Llandudno, anyway?
I used www.distance.to to calculate the great circle distance between the approximate centres of both areas as 112 km. These locations are actually quite close to the Oasis 3D sites Carraghan, IMN and Builder Street West, Llandudno, Wales, GBR.
To make sure I am looking the right direction I decided to place a large visible marker (we call them 'Search Rings') in Llandudno.
To make it easier to visualise the search area at different scales I placed two search rings, both centred on the same Post Box. The second image shows that I'm working in just a single tile - apparently floating in space!
This short video shows the difference in size between the search rings and the extents of the tile:
This video moves from Conwy Sands to Llandudno and the Great Orme.
Assumptions:
By this point I have more or less arbitrarily decided on 'Llandudno' being three locations. The first is the post box and the inner search ring. I'm pretty sure I won't be able to see that - but who knows?
The second is the 1km wide outer search ring. I'm pretty confident I will be able to see that. The third 'area' is just the entire stretch of coast from the Little Orme in the East to the Great Orme in the West.
Switching to the Isle of Man I checked what you can see from the Isle of Man at the classic Spy Balloon altitude of 60,000'. Scotland, Ireland, Wales and England are all clearly visible:
But what could a normal person expect to see? From the summit of Carraghan I took a number of images using different lenses.
The Oasis 3D lens closest to the human eye is 35mm (2nd image). This suggests that from the top of Carraghan on the Isle of Man (on a clear day) you can see the general landmass of North Wales the mountains beyond - but not very clearly.
The largest Oasis 3D lens available with the slider has 200mm focal length. For the spy-balloon simulation we added a manual override up to 900mm.
The 1 km wide outer search ring is visible with both lenses. With the 900mm lens you can start to see the general colour of the terrain. Nowhere close to seeing the post box!
However... this is only half the story. You can see (vaguely) Llandudno from Carraghan summit. But what can you see from other locations? Such at the beach at Douglas.
Before leaving the summit I checked the (x,y,z) location of the camera viewpoint I had been using. The z value (527.731) is the height in metres above the reference ellipsoid, a.k.a. sea-level. box!
Carraghan Camera Location
From Carraghan I headed in the direction of Llandudno until I reached the coast. On the beach I placed a 1m wide search ring and set it to 527m high with a camera at the top and the bottom.
Camera at 527m
Camera at eye-level on the beach
From the high view there is not really much difference from the view at Carraghan summit. From the sea-level view - nothing! At sea level on the Isle of Man you cannot see North Wales at all:
View from 527m
View from the beach
This final video shows the coast of North Wales disappearing below the horizon as you descend from 527m to sea-level:
TL;DR:
You can see Llandudno from the Isle of Man - if you are quite high up on the Isle of Man and define 'Llandudno' as a vague section of the North Wales coast roughly between the Little Orme and the Great Orme.
If you are low down (i.e. sea-level) then you can't see North Wales at all.
Postscript
The Isle of Man is surprisingly hilly. On www.viewfinderpanoramas.org I found this image of the view from 620.0m on Snaefell summit, the highest point on the Isle of Man. If I had come across this earlier I would have used Snaefell as my viewpoint rather than Carraghan:.
© dhp11 Ltd. 2022
