Ever since I found that you could view 1:50000 scale OS maps (streetmap/multimap etc) on the net, I'd thought about writing some software to download them and then stitch them together to form more usable larger maps. I'm glad I haven't yet had the time as I've just found someone else has already done it. TrailGauge Map Grabber is a nifty little programme that lets you specify a point anywhere in the UK and using that point as a central position will download a map as wide and as tall as you require. Because the maps are web based they only have a resolution of 96dpi, so to make them clearer for printing use the 'sharpen' function in any photo/paint package. It's also best to then to convert the image from truecolour down to indexed-256 colour (but only after the sharpen).

One of the best uses for these maps is to load them in to a suitable GPS programme, such as GPS Utility and then planning a route and uploading it into your GPS is as easy as ... well GPS.

Now when are they going to put 1:25000 maps on the net?

Oh and of course do not use Map Grabber to infringe the copyright of the OS, Mulitmap, Streetmap etc.

i only need a printer big enough!

Cheers Mike - something I've thought about doing too. I only got as far as an HTML generator, which can be used to semi-automatically produce Polaris / ACE race maps from checkpoint coordinates (hackware at the moment, as the code needs changing for each application).

How big does it need to be, to take in the whole of GB?

Andrew do your own maths!
(You can cover mainland GB with 812 20km squares and after proccessing each square is about 8MB).

Thanks Mike - am now busy downloading.

Wouldn't mind building my own version of this, as the database of names is a bit limiting.

Does anyone have a good formula for converting LAT/LONG to OS Grid. I've got a huge list of towns etc from the GPS guys in a spreadsheet that I'd rather have in OS format.

Chris - Would you be prepared to share your code???

I don't know whether any of you have checked the Trailgauge website recently but the Map Grabber has been withdrawn for 'commercial reasons'.

It is pretty obvious what these 'commercial reasons' might be - I wonder if they came from our wonderful public serving mapping agency ?

I might still have the setup file on my drive (next to the BMW and the Lotus). If anyone wants it, e-mail me I'll have a look for it though it might take a day or two.

Which version have you got Dan, there was the original version that only supported Multimap and then there was a newer version that did Streetmap aswell and allowed you enter a grid reference ?

Might ( :-) ) have the one which does both. The thing that really impressed me was the 'Find Place' feature, where as you typed in the name of somewhere a list of places appeared, and the more of the name you typed the shorter the list of possibles got.

http://jg4fun.1accesshost.com/mapgrabber/mapgrabber.html

just downloaded it but when I try to download a map all I get is a black square!
:-(

Unfortunately it seem that Multimap now look at look at multiple accesses to their maps and returning a blank page every now and again. This means if you try to download a 20km square map, you'll end up with a few black tiles (usually covering the area you're most interested in). The only way around this is to manually use a browser to grab the missing areas from the multimap web site (set the scale to 25,000), then 'stitch' these into the main map.

I always thought the black tiles thing was down to some problem with my puter, so it's interesting to hear that they're put in deliberately. Not that it makes it any less of a pain.

As Paul says, it's not just a few black tiles anymore, it's a picture of a black cat in a coal bunker at night with its eyes shut. Shame as it was quite usefull.

They had to shut it down :-( due to comercial reasons. DOH!

I've managed to get hold of a new verion that uses streetmap.co.uk If any one wants a copy just ask or go to the GPS Utility User Group you'll have to join and it's under the 'files' section.