Graham_Wright
Well-Known Member
Beaver Bay shows in different positions with Vessel Finder and Marine Traffic.
Interesting.
Interesting.
AIS disparity
- Thread starter Graham_Wright
- Start date
pvb
Well-Known Member
Vessel Finder shows a position 3 hours old. See how old the Marine Traffic position is...
Lucky Duck
Well-Known Member
Beaver Bay???
Graham_Wright
Well-Known Member
Quite so. My son is in command and brought the tug from Invergordon to Nigg Bay. The plot stopped at Longhaven but the boat didn't! This was some time ago.
Hoolie
Well-Known Member
It's also affected by their ability to monitor vessels. They really do not have 100% coverage so boats/ships appear to stop at the edge.
pvb
Well-Known Member
Odd though that one of the AIS-reporting sites gave a position only 3 hours old, whereas the other gave a position over a month old.
ithet
Well-Known Member
Don't these services rely on networks of amateur enthusiasts with shore based AIS receivers feeding in data? Assuming they have differing groups of data suppliers the coverage and timing of data would differ. These are not official tracking services.
I might be wrong, but that is as I understand these ship tracking services.
I might be wrong, but that is as I understand these ship tracking services.
pvb
Well-Known Member
Yes, you're right, they do depend on a network of helpful amateurs. But the tug is near Aberdeen, not exactly a wilderness, is it? Oh....
GHA
Well-Known Member
They are displayed on screen, though you might need to turn on a filter, lots of data about targets as well . Seems odd the tug ins't being seen apart from on vesselfinder
greeny
Well-Known Member
It happens to me all the time. I'm on one and not any of the others. Then a few days later in a different location the situation reverses. I'm sure it's to do with where the receiving station is and which system is taking data from where. I don't think it can be a universal integrated system in the web based system. Different companies may be getting data from different stations, interpreting and displaying it differently.
pvb
Well-Known Member
Yes, I think that's the problem. I'm glad I don't have an AIS transceiver, so have none of these worries!
Frankklose
Well-Known Member
With the newer Ais B+ it's picked up by satellite and updated every 3 minutes.
TernVI
Well-Known Member
These sites are more for entertainment than serious information.
Lucky Duck
Well-Known Member
Some might recall the member of this forum who took exception to his boat's movements being displayed on these sites and got quite worked up about it - to the point of asking them to not display his boat.
[70521]
Well-Known Member
But big brother is still watching.
Graham_Wright
Well-Known Member
Who is "them"? The mods or the AIS administrators? If the latter, he could switch off.
MarkCX
Well-Known Member
Isn’t letting people see where you are, rather the point of AIS? ??
johnalison
Well-Known Member
I can imagine that the said gentleman wanted to increase his safety by making his boat more visible but objected to the idea of me sitting at home and watching him (or maybe his boss/wife). I can't say that it has worried me and I rather enjoy having my small club of stalkers when I am away.Isn’t letting people see where you are, rather the point of AIS? ??
Graham_Wright
Well-Known Member
The response I received from Marine Traffic follows;-
Dear Graham,
Thank you for your post.
I would like to confirm that indeed the latest position received from Beaver Bay has been on 22-06-2020 at 01:55 UTC.
Please allow me to mention that the lack of Updated Positions of a vessel can be a result of a number of factors.
Signal strength, functional transponder, local (vessel area), and surrounding (nearby stations) weather conditions, temperatures, traffic, and the satellite constellation frequency are some of the most important ones.
You can learn more about them here:
Why cannot I see a vessel on the Live Map?
I would also like to note that we are using and relying on our own terrestrial stations and upon checking I can confirm that there is a low coverage in the area the subject vessel is sailing now.
I hope I was able to help you with your concern.
Should you need any further assistance or clarifications feel free to contact us.
Kind regards,
Lucky Duck
Well-Known Member
He reportedly contacted the operators of marinetraffic and the like demanding they stopped displaying his boat.