Port history

[Henrik Soderberg]

Hi everyone,

If you have not noticed already - we added the "port history" box below the photo and ship information yesterday.

This is the intended destinations and estimated time of arrival that is sent out by the ship itself through AIS. Obviously we can't guarantee that the information is correct, or that the vessel has actually been there. It could have been changed, cancelled or we just missed pieces of information in case the vessel was out of AIS range for a while.

The quality and functionality of all the new data we have presented the last week will be improved in many ways. As this kind of information has been requested a lot, we have released it now as we feel it's good enough to be presented. Also, please report bugs or problems as usual, should you find any.

Regards,
Henrik

[The Catman]

Thanks - looks a very useful addition to the site

TC

[Robert Smith]

Great gadget - I just found out I made a unique picture this afternoon !
Keep up the good work. It's appreciated.

Ciao,
Robert.

 

[Danijela Dani Paljusic]

This is great, and I see that are left out some ports in which some ships sailed.

But there are a lot of information and super.

Regards,

[Danijela Dani Paljusic]

And, of course,


THANKS!!! 

[jdap]

Can you please confirm that the "Port History" module is indeed what the title name entails: i.e., "history" of calls by a given ship, not, repeat, not a forecast of future ports of call by that specific ship.

Indeed, I am rather confused here.

Let me show you an example (one of many):

http://www.shipspotting.com/gallery/photo.php?lid=1535687

Today we are on Sep. 4, 2012.

This being so, the ship port history should end around this date. Instead, it extends all the way through December 2012...and it even indicates a time of arrival (?) on Dec. 2 at Lisbon which is precise to the minute and even to the second: 07:00:42 UTC (!)

How can this be?

If what the module is showing is both "Port History" and "Port Forecast", I submit the title should say so.

And should it be also a forecast, then the ETA should be limited to a date, not to a time of atomic precision several months hence...

Just a thought...(by a confused site user).

Jos

[Phil English]

Jose,

As Henrik explains at the beginning, this information is derived from the vessel's AIS signal. As such, it can only be a history and a short forecast of current voyage ETAs based upon previous and currently transmitted signals. The problem with AIS is that it relies on shipboard personnel correcly inputting data and software correctly decoding the signal. Unfortunately, both are prone to error, hence the problems that you see. It is not really a fault of the shipspotting.com, as you will see similar issues with almost all AIS tracking websites. As Henrik also says, the information cannot be guaranteed!

Brgds
Phil

[Kelvin Davies]

Hmmm.
Not sure about the definition of 'short forecast' now.
It has an ETA there for December 2nd 2012 (3 months ahead)!
Kelvin

[Phil English]

Kelvin, perhaps I should rephrase my comment to say 'should' only be a history and short forecast. Due to the issues I highlighted, the displayed dates are prone to be spurious.

In any case, as Ken says, we are aware and it has been reported to the technician.

Brgds
Phil

[jdap]

Gents,

Many thanks for taking the time to look up this issue and for providing me immediately with all your answers.

I derived two conclusions from your inputs:

1. (and foremost) - "Port history" info as reported is not, of course, under Shipspotting control.

2. - "Port history" should be read with caution at all times, as info there is AIS-based, and it may be incorrect or misleading.

Again, many thanks to you all for your contributions.

Jos