Author Topic: How up to date a satnav map is - does it matter?  (Read 8721 times)

ianj37

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How up to date a satnav map is - does it matter?
« on: November 30, 2014, 04:31:00 PM »
Here's a discussion point as the dark nights draw in - I'm battling with a slight dilemma here and would welcome some advice from more experienced folks.

Until early this year I was a very satisfied Satmap user but when it had to go back to have the USB port cover I'd ripped off replaced an offer on a Garmin GPSMAP 62s in a local store  became irresistible even though the Satmap was due back in 7 days (largely because I like gadgets and have no will power). So now I've got both but that's just a waste so one has to go.

There are pros and cons on both sides but overall I think the Garmin wins in functionality but a clear key difference is that whilst Satmap seem to produce a new map as soon as OS release it the Garmin maps are, as far as I can see, years out of date. Garmin have told me that the OS 1:25k maps bought on a card or as a download from BirdsEye mapping are based on the same version of the OS map and I can see that there were changes made to the Dark Peak OS map in 2010 that show on the SatMap map but aren't on the Garmin map. I've asked Garmin when they update the Birdseye mapping and the answer was they don't know if or when they will do it. I've tried the TalkyToaster maps but I really want OS. Maps from Satmap cost more than those downloaded from Garmin but fortunately that's not a problem.

So does it matter that the map is out of date? I can argue both ways:
Where's the point in having a device with an out of date map, to a degree might as well not bother having a map on it.
If I need to get down from the hills quickly in bad conditions being able to see the nearest footpath without having to struggle with a map would be good.
Boundaries and concessionary footpaths come and go and one should respect these.
or
I always have a map and compass with me anyway so I can use those to check
OS take time to produce a map so even the most recent won't be 100% with the ground
If I need to get down quickly in Open Access land why would I bother looking for a path

So, there's a taste of the dilemma, not the most earth shattering I agree but I'm interested to know what folks think. All contributions welcome. I posted here because this is a very civilized forum, I expect on others I'd just get beaten up!

« Last Edit: November 30, 2014, 04:34:13 PM by ianj37 »

boogyman

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Re: How up to date a satnav map is - does it matter?
« Reply #1 on: December 02, 2014, 07:40:44 PM »
Are both maps the same scale? I've had several times the following experience: a newer topo, scale 1:50K, did NOT show a narrow path which WAS shown on an older 1:25K topo. So age (of the topo) is not the only parameter.

My 2p.

captain paranoia

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Re: How up to date a satnav map is - does it matter?
« Reply #2 on: December 02, 2014, 11:04:52 PM »
All maps are immediately out of date when they're printed/published...

It's just a case of how out of date, and how frequently things change.  My general experience is that, away from urban areas, things don't change very quickly.

The DofE girls do have rather old maps (even though I hand out more recent paper copies for all of them), but I can only recall one instance when they took a path "that wasn't there"...  Oh, then there's the gravel extraction in the area we use, which does cause some fun & games; "this enormous water-filled hole shouldn't be here..."

Hugh Westacott

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Re: How up to date a satnav map is - does it matter?
« Reply #3 on: December 03, 2014, 08:41:54 AM »
I don’t like satnavs that display maps on a screen so I use a Garmin Fortrex 401 in conjunction with Ordnance Survey that maps I print from Grough software.

The following question was raised in April 2013 on the Grough help forum:

I'm working on a route in the Monadhliath area, which I will need for my TGO Challenge trip in May.  The current maps on Grough are out of date, missing the new tracks in the Glen Doe Reservoir area. (e.g. NH 460 040).  These are shown on paper maps bought back in January (Landranger 34 & 35)  Is there any chance the online maps will be updated before May 7th as I would like to print off my route with an up to date map.

The Editorial Director replied:

We're currently working on processing higher-resolution mapping for the system, which is a major task and is the reason some mapping areas are not up-to-date. I can't give you a definite date for the update I'm afraid, but I have made our technical staff aware of your request.

As far as I know, there is no method of establishing the edition of the map on which software maps are based, but it’s easy to do from OS sheet maps if you understand the formula. This is an extract from the manuscript of my forthcoming book The Walker’s Handbook; Everything You Need to Know about Walking in the British Isles:

Maps in both Explorer and Landranger series are revised regularly and this information, together with the copyright date of the edition, is shown on the key. The extent of the revision is indicated by a code made up of a letter followed, in some cases, by a number:

a)   When a sheet is fully revised the edition letter is advanced, e.g. from A to B, and the copyright date is changed.
b)   When a sheet is revised with significant changes the edition letter is unchanged but a number is added or advanced, e.g. A to A1 or B2 to B3, and the copyright date is changed.
c)   When a sheet is reprinted with minor changes the edition is underscored, e.g. A2 to A2, and the copyright date remains unchanged.
d)   Note that the copyright date alone appears on the 1:50,000 and 1:25,000 maps published by the Automobile Association and Geographia.

Information about the latest edition of any Landranger or Explorer map may be obtained from the Ordnance Survey website (www.ordnancesurvey.co.uk).

(End of puff!)

It is helpful to know the date and the extent of any subsequent editions of OS maps. Some years ago I was walking in Kent relying on an Explorer map from my extensive map library. I came to a railway line where the map indicated that I should turn right. This I duly did and got hopelessly lost until I finally worked out that I had mistaken the HS1 line to the Channel Tunnel, which was not marked on my map, for the railway line that ran parallel to it but some distance away.

I make a practice of annotating my maps by marking paths and other significant features that are not depicted.

Hugh
I grow old…I grow old, I shall wear the bottom of my trousers rolled. T. S. Eliot

ianj37

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Re: How up to date a satnav map is - does it matter?
« Reply #4 on: December 03, 2014, 08:06:35 PM »
Thanks for all the helpful comments. From Hugh's information I can see my paper map is the OS 1:25k Dark Peak map edition A4, revised 2002, revised for selected change 2010 and copyright 2011. Curiously there doesn't seem to be a way to look on the OS web site and see the version/revision details for their maps.

Both SatMap and the Garmin Birds Eye are 1:25k, in the area where I know there's a difference the SatMap version matches the paper version. I visit the area regularly and OS/SatMap matches ground.

This is the problem area that I know of with, depending on how you count them, up to 5 differences, but to be fair there may be no more, from Birdseye version:

 

and this is the same area from the SatMap/paper version They are definitely both 1:25k, I've cut these from the screen and the slight difference in size is how they display on my screen.



At the moment I'm tempted to stick with Garmin given that the most recent SatMap really was a feeble attempt at an upgrade but then I'm rewarding poor customer service and poor instruction manuals whereas SatMap staff are amazingly helpful, they keep their maps up to date and their manual is like the encyclopaedia Britannica!
The SatMap people are coming to Cotswold's shop in Nottingham this month so I might go and see if they reveal any plans about software upgrades which will make the decision a little easier!


captain paranoia

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Re: How up to date a satnav map is - does it matter?
« Reply #5 on: December 03, 2014, 10:29:15 PM »
The vertically-compressed image from the Garmin suggests it may be reprojected to angular coordinates.  I can't think of another reason why you'd do such a vertical compression.

Since there may also be a rotation (though it's hard to tell), that would also suggest some form of reprojection, showing up the grid convergence that occurs with the OSGB projection.

I wonder if it's doing reprojection on the fly, or whether the mapping imagery has all been reprojected.  If the former, there may be a setting somewhere to use OSGB projection...

Hugh Westacott

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Re: How up to date a satnav map is - does it matter?
« Reply #6 on: December 05, 2014, 07:53:21 AM »
<From Hugh's information I can see my paper map is the OS 1:25k Dark Peak map edition A4, revised 2002, revised for selected change 2010 and copyright 2011. Curiously there doesn't seem to be a way to look on the OS web site and see the version/revision details for their maps.>

The most likely explanation is that the OS only sells the latest edition. I've always found Customeer Services very helpful and you should get a response from an email querying whether your edition is the latest. I don't know of another source for the information you require.

Hugh
I grow old...I grow old, I shall wear the bottom of my trousers rolled. T.S.Eliot

ianj37

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Re: How up to date a satnav map is - does it matter?
« Reply #7 on: December 05, 2014, 02:20:55 PM »
Thanks for the additional information.
CP - I'm not sure I understand the technicalities of your points about compression and rotation but the images I posted are 'snipped' with the Microsoft tool from my PC screen so it may all be down to the fact that I'm using a wide PC screen. Although I don't seem to be able to zoom them to 'life size' on the screen i.e where a grid square is 4 x 4 cm

Hugh - I take the point that OS would only sell the most recent version but I was wondering how I would know whether I had the most recent version of a map other than buying it. I'm afraid I haven't found OS Customer Services as good as you have but to be fair that was only one occasion so really I'm being a bit unfair, I asked whether they had an up to date version of OL1 that would work on a Garmin and heard nothing. This I'm assuming means that they know that the Garmin maps they sell on SD cards don't contain the most recent version of their maps.
By the way when is your book expected out?

captain paranoia

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Re: How up to date a satnav map is - does it matter?
« Reply #8 on: December 05, 2014, 07:33:43 PM »
If both of your pictures are cut from screen snapshots taken from the same display device (e.g. A PC screen), rather than being captured on different devices, then it certainly seems that the Garmin imagery is distorted.  Certainly vertically compressed.

Do the pictures above look like they look on your screen?  I realise that's a tricky question, because you'll be looking at them on your screen...  I mean how they appear in their respective programs on your computer, not on this forum (and browser...).

If you have Garmin mapping for an area to extreme East or west of Britain, have a look at the grid lines.  If they're not orthogonal (at right angles, i.e. parallel to the edges of the window), then they're probably re projected in some way.  Vertical compression would suggest reprojection to an angular pixel spacing.

As an example of the difference between angular-spaced pixels and OSGB projection, linear-spaced pixels, have a look at the images I posted on this thread.

Hugh Westacott

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Re: How up to date a satnav map is - does it matter?
« Reply #9 on: December 06, 2014, 10:35:14 AM »
Ian

I've contacted my chums at the OS to ascertain whether there is any source that provides information about the latest editions of Landrangers and Explorers.

I've also posted the same query on ordnancemaps@yahoogroups.co.uk which is a forum devoted mainly to historical maps. It's a great academic forum for those of us who are interested in OS maps and I've learnt a lot of fascinating information from it although much of it has little relevance for practical navigators.

I'm hoping that my book will be published next spring.

Hugh

Hugh Westacott

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Re: How up to date a satnav map is - does it matter?
« Reply #10 on: December 06, 2014, 05:58:57 PM »
Ian

The information you require can be found at
http://www.ordnancesurvey.co.uk/docs/collateral/ordnance-survey-leisure-map-catalogue.pdf.

If you are interested in viewing the edition history of individual maps go to:
http://www.watsonlv.addr.com/os-maps.shtml

The information was supplied by a member of the ordnancemaps@yahoogroups.co.uk forum.

Hope that this is helpful.

Hugh
I grow old...I grow old, I shall wear the bottom of my trousers rolled. T.S.Eliot

ianj37

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Re: How up to date a satnav map is - does it matter?
« Reply #11 on: December 08, 2014, 08:00:34 PM »
Again I'm very grateful for the interest and for the helpful suggestions.

CP - I've checked on the devices (Active 10 and GPSMap 62s) both maps display as you would expect/hope - the OS grid lines do form a square, I'm measured them both, but on the screen they are different. SatMap forms a square but Garmin is 74mm wide x 53mm high. The footpaths are missing on both the PC and device views for Garmin so I'm assuming it's not this display issue which is causing my main problem. On another subject the Silva Map Measurer has yet to arrive - lost in the Christmas post I guess!!

Hugh - Thanks for the information again. It's only by scrolling though the catalogue that I fully appreciated the number of maps the OS produces and supports - somehow the key on the back of the map doesn't bring it home to me. I was going to get another OL1 map is I bought mine 2 years ago and assumed it must have been updated but looking at the links you provided I can see that's not the case, so you've saved me the cost of a new waterproof map - thanks for that, I'm very grateful. 

Hugh Westacott

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Re: How up to date a satnav map is - does it matter?
« Reply #12 on: December 15, 2014, 02:22:49 PM »
Here is the text of an email I have sent to the Ordnance Survey's Custopmer Services:

I know that the OS likes feedback from map users so I trust that these comments may be helpful:
 
1          I confess that I overlooked  the ‘Show more’ link that would have provided me with the information I required for a specific map..
 
2          However, although this is useful if you are just checking the edition of one map, it’s rather a cumbersome and time-consuming method if you are checking a number of maps.
 
3          There appears to be no obvious link from the Home Page to the map catalogue. The only way to discover that the catalogue exists seems to be to enter ‘Map catalogue’ in the search box.
 
4          I think, and I know that I’m not alone in this, that it would be helpful to add links to the catalogue from 'Paper maps’ (https://www.ordnancesurvey.co.uk/shop/maps.html).
 
Hope that this is helpful.


My email has been acknowledged and I have been informed that the suggestion has been forwarded to the OS web team for consideration, and that I can expect a response by the 24th December.

Hugh
I grow old...I grow old, I shall wear the bottom of my trousers rolled. T.S.Eliot
 
« Last Edit: December 15, 2014, 02:30:14 PM by Hugh Westacott »

ianj37

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Re: How up to date a satnav map is - does it matter?
« Reply #13 on: December 16, 2014, 04:51:50 PM »
Thanks for that Hugh, I'll be interested to hear what they say. On the basis of your positive comments about OS I've resent my message about why don't they produce maps for handheld devices based on the most recent OS maps and if I get a reply I'll post it here.

Hugh Westacott

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Re: How up to date a satnav map is - does it matter?
« Reply #14 on: December 22, 2014, 08:10:29 PM »
I've received the following email from the OS

Hello Hugh
 
Thank you for your reply.
 
This has been passed to our support team to consider and the response we have is that they are already dealing with this and it is on their development backlog. They will consider this in the future.
 
Thank you for taking the trouble to notify us.
 
Your reference for this is GV-149009
 
Kind regards
 
Neil.
 
Neil Wilson
 
Customer Service Adviser
Customer Services,Ordnance Survey
www.ordnancesurvey.co.uk | customerservices@ordnancesurvey.co.uk
Adanac Drive, SOUTHAMPTON, United Kingdom, SO16 0AS
Phone: +44 (0) 3456 050505 | Fax: +44 (0) 3450 990494


So it seems likely that a link to the map catalogue will be provided.

Hugh
I grow old...I grow old, I shall wear the bottom of my trousers rolled. T.S.Eliot