Navigation with mobile phones

codprawn · 05 September 2007, 14:50

This is bound to start another lively debate....

Yesterday I watched the Mumbles lifeboat tow a Rinker back to Swansea marina. I thought it had just run out of fuel but it turns out it had run aground on some rocks.

http://www.thisissouthwales.co.uk/di...pNodeId=161375

Video footage as well.

What scared me was that by looking at the electronic charts I could well have done the same. Once again it's fine for an oil tanker who would just steer well clear of the shallows but smaller boats such as ours are great for coast hopping.

Unfortunately - as has been discussed before - the charts just show an even shallow area - there's nothing to tell you about the odd rock or even island sticking up etc. I really thought something so obvious would be marked!!!

The BEST thing for showing what a coastline is really like is Google Earth - you can even see the rocks so it's ideal for picking your way through a rocky inlet. Wouldn't it be nice to use it on a boat.

I have just had a new mobile phone - the Nokia N95 - it has GPS built in so you can use it for satnav - it also has GPRS so you can connect to the net - once connected you can use Google Earth and it overlays your GPS position so you can SEE exactly where you are!!!

Again Ordanance survey maps are also brilliant for coastal work.

BogMonster · 05 September 2007, 16:56

I have looked on Google Earth before going places and it does show up quite a bit of detail regarding shallows - as long as you are in an area with good coverage! The coverage around here varies from excellent to very low-res, very odd pattern of good and bad areas with not much logic behind it!

You need a VSAT terminal on your rib Codders

Bigmuz7 · 05 September 2007, 17:47

I found the N95 Sat Nav pretty rubbish, it took forever to load a position, and it looses its fix from time to time. Land detail is fairly poor and its use pretty limited imho, I have never tried it with google however, and I wondered if their might be a software update for the sat nav to make it more usable, plus the receiver is so week , you have to hold it out in front of you at a 45 degree angle to get a fix to start with. Nice idea, but I'll stick with my Ray-marine C120 thank you, its detail is immense, and I've used it to locate to some very small rock formations so far.

I'm not sure if it uses solely the Admiralty charts for its data, but with a fine zoom, its well accurate, and the 12 inch display is excellent in any light

codprawn · 05 September 2007, 18:27

The N95 software is crap - espcially the mapping. You can use TomTom on it though and you can use proper maps and charts. The GPS seems to work pretty well - just takes a long time to aquire but then it's ok - maybe the new software has fixed it.

I also have a Raymarine and love it. It was the Garmin Bluechart maps I have been looking at but from memory the Navionics Gold aren't that amazing close in either.

jwalker · 05 September 2007, 18:34

What is the lat and long of that incident, Codders?

codprawn · 05 September 2007, 21:43

Here are examples of Google Earth - Garmin Bluechart and OS 1:25000 maps. It is pretty obvious the Bluechart doesn't show much real detail close in. Great to stop a tanker running aground but not much use to smaller boats.

Biggles · 05 September 2007, 22:43

Wheres that guy that got on his orange box last time we talked about using non marine charts/maps for more information.

Seems pretty clear from Codders pics that the Garmin stuff is the one that shows the least information about that nasty bit of rock in the east of the cove.

Hopefully give it a year and all GPS stuff will be using Google type pictures. It seems to be the future.

Now just remembered must switch off that evil chartplotter and get out that quaint compass.

Bigmuz7 · 05 September 2007, 23:07

Wheres an admiralty chart of the same bay ?

Bigmuz7 · 05 September 2007, 23:17

their website wants £45 for one !! Anyway codders that google snaps fom your PC!

codprawn · 05 September 2007, 23:22

Quote:

Originally Posted by Bigmuz7

their website wants £45 for one !! Anyway codders that google snaps fom your PC!

Google Earth is Google Earth - wether it's on a phone or a PC!!!

codprawn · 05 September 2007, 23:23

Quote:

Originally Posted by Bigmuz7

Wheres an admiralty chart of the same bay ?

Yes I would like to see the detail on one - can't find the one I used to have!!!

Biggles · 05 September 2007, 23:30

But that Google pic is so clear as to the dangers in that area its brilliant. Even a child could understand that a boat should not be where the rocks are.

The google pics with depths and contours overlaid will make fantastic charts in the future.

codprawn · 05 September 2007, 23:33

Yes aerial/sat images are the way to go - no doubt they will come in. As the penguin points out though there are many areas not covered yet!!!

Biggles · 05 September 2007, 23:41

Thats free areas. If you want to pay you get much more.

I have the whole of the south of england and wales from a different source to google which I have bought and this shows many areas that google haven't released as a freebie.

codprawn · 06 September 2007, 00:08

Quote:

Originally Posted by Biggles

Thats free areas. If you want to pay you get much more.

I have the whole of the south of england and wales from a different source to google which I have bought and this shows many areas that google haven't released as a freebie.

You don't get any more detail if you buy the full versions of Google Earth - only more features. It may be different with 3rd party addons - what are you using???

Any chance of some piccies of Burry Port/Lougher???

jwalker · 06 September 2007, 00:20

To be fair, the land on the chart (brown) follows the land on the google pic (green); the drying area on the chart shows that rock as drying to 1.4mts and further along it's drying to 2 and 2.5mtrs. I agree it could be more clearly shown a rock ledges but if you know the tide's low you wouldn't want to boating over a negative drying area.

codprawn · 06 September 2007, 00:34

Quote:

Originally Posted by jwalker

To be fair, the land on the chart (brown) follows the land on the google pic (green); the drying area on the chart shows that rock as drying to 1.4mts and further along it's drying to 2 and 2.5mtrs. I agree it could be more clearly shown a rock ledges but if you know the tide's low you wouldn't want to boating over a negative drying area.

If that was the case nobody would use Burry Port harbour or many others in the UK. As I say it doesn't matter if you are in a big ship - you would stay well away but smaller boats use drying areas all the time at suitable tide times. You would expect nasty rocks etc to be marked somehow!!!

Jono · 06 September 2007, 12:06

Be wary of "Google Earth".. it is not all it seems... some of the images are tinkered with...

Waterman · 06 September 2007, 12:23

On the new blue chart software if you click on view you have an option to view your routes in google earth. Its brilliant!!!

codprawn · 06 September 2007, 12:59

Quote:

Originally Posted by Waterman

On the new blue chart software if you click on view you have an option to view your routes in google earth. Its brilliant!!!

Fine if you have a nice sat connection - not many RIBs have the space for a gyro stabilised dome!!!