+lifechooser Posted June 10, 2011 Share Posted June 10, 2011 This isn't strictly a geocaching question, but I'm planning an ascent of Scafell Pike, and I want to put a few key waypoints into my etrex - which doesn't have a data cable. I can't seem to find any way of getting the waypoints from a map, which is in the correct geocaching style format. I've been using maps.bing.com as it has an OS mode, but I'll take any suggestions. Quote Link to comment
+mcwomble Posted June 10, 2011 Share Posted June 10, 2011 Try streetmap.co.uk instead and hit their handy "convert" button. You'll have to convert the DD.ddddddd to DD MM.mmm yourself but thats a handy divide by 60 for the .ddddddd part. Quote Link to comment
+lifechooser Posted June 10, 2011 Author Share Posted June 10, 2011 (edited) Try streetmap.co.uk instead and hit their handy "convert" button. You'll have to convert the DD.ddddddd to DD MM.mmm yourself but thats a handy divide by 60 for the .ddddddd part. So near the summit is 54.27.17 3.12.47. How do I convert that to DD MM.mmm? Edited June 10, 2011 by lifechooser Quote Link to comment
+NattyBooshka Posted June 10, 2011 Share Posted June 10, 2011 (edited) Try streetmap.co.uk instead and hit their handy "convert" button. You'll have to convert the DD.ddddddd to DD MM.mmm yourself but thats a handy divide by 60 for the .ddddddd part. So near the summit is 54.27.17 3.12.47. How do I convert that to DD MM.mmm? Why convert? Quickest way is just to switch the eTrex into DD.ddddddd/DD MM SS.s and tap them in! From what I see, the GPSr stores in decimal degrees format anyway and translates to/from DD MM.mmm co-ordinates that we are used to seeing. I think the eTrex series all are capable of of taking OS grid references too. When you're done, switch the eTrex back to it's default settings (which this site uses) Edited June 10, 2011 by NattyBooshka Quote Link to comment
+Simply Paul Posted June 10, 2011 Share Posted June 10, 2011 (edited) So near the summit is 54.27.17 3.12.47. How do I convert that to DD MM.mmm?That's 54deg 27 min 17 sec North and 3deg 12 min 47 sec west. The Degrees and Minutes stay the same but divid the seconds by 60. eg: 17 sec becomes .283 of a minute. So 54.27.12 becomes 54 degrees 27.283 mins north and 3.12.47 becomes 3 degrees 12.783 mins west. (You have to round to three digits after the decimal point) - Hope that helps! Edited June 10, 2011 by Simply Paul Quote Link to comment
+lifechooser Posted June 10, 2011 Author Share Posted June 10, 2011 Thanks both. Switching format had never occurred to me! That will be the easiest as I already have the co-ords in DD.ddddddd format. However I may need to use Paul's method to enter it into my phone if I set it up as a backup. Quote Link to comment
+NattyBooshka Posted June 10, 2011 Share Posted June 10, 2011 Thanks both. Switching format had never occurred to me! That will be the easiest as I already have the co-ords in DD.ddddddd format. However I may need to use Paul's method to enter it into my phone if I set it up as a backup. My sat nav uses DD MM SS.sss and I'm a paperless/random cacher, so I download on the phone, tap into eTrex, and then switch eTrex to the sat nav's format... so I'm used to the process, and am getting a lot quicker at doing it! Quote Link to comment
+Bear and Ragged Posted June 10, 2011 Share Posted June 10, 2011 Thanks both. Switching format had never occurred to me! That will be the easiest as I already have the co-ords in DD.ddddddd format. However I may need to use Paul's method to enter it into my phone if I set it up as a backup. Make sure you change the Datum as well! Quote Link to comment
+Bear and Ragged Posted June 10, 2011 Share Posted June 10, 2011 The correct one! Caching uses WGS84 OS uses OSGB If you enter one set of co-ords in the other Datum, and change settings you'll be in the wrong place! Quote Link to comment
+Simply Paul Posted June 10, 2011 Share Posted June 10, 2011 Good point. The wrong Datum can send you anything up to 300m off-course so, especially somewhere with hazards like a mountain, it pays to get it right. Quote Link to comment
+lifechooser Posted June 10, 2011 Author Share Posted June 10, 2011 The correct one! Caching uses WGS84 OS uses OSGB If you enter one set of co-ords in the other Datum, and change settings you'll be in the wrong place! What does Bing maps use? Quote Link to comment
+Bear and Ragged Posted June 10, 2011 Share Posted June 10, 2011 The correct one! Caching uses WGS84 OS uses OSGB If you enter one set of co-ords in the other Datum, and change settings you'll be in the wrong place! What does Bing maps use? Good question. Can't find anything on the site to say... Very poor! Quote Link to comment
+Bear and Ragged Posted June 10, 2011 Share Posted June 10, 2011 (edited) Just a thought. Take a look at http://www.walkhighlands.co.uk/ you may have to register, but it's free. They do maps, and have map/route planning. AND it's Ordnance Survey. May even have a ready-made route you can download and print. If you use their map refs, set your GPS to OS and OSGB Datum, enter map refs, then when you change back to WGS84 and HDD.MMM all should be fine. Edited June 10, 2011 by Bear and Ragged Quote Link to comment
Copepod Posted June 10, 2011 Share Posted June 10, 2011 Anyone planning an ascent of Scafell Pike needs to take a paper map and compass - no batteries to run out, and even in the dark, you'll still be able to read a bit. Be sure you understand the difference between Scafell Pike (978m) and Scafell (964m) - the two tops are linked by a col called Mickledore. Wasdale Mountain Rescue Team volunteers have to guide / rescue far too many inexperienced / ill-equipped people off England's highest peak. Quote Link to comment
+NattyBooshka Posted June 10, 2011 Share Posted June 10, 2011 Just a thought. Take a look at http://www.walkhighlands.co.uk/ you may have to register, but it's free. They do maps, and have map/route planning. AND it's Ordnance Survey. May even have a ready-made route you can download and print. If you use their map refs, set your GPS to OS and OSGB Datum, enter map refs, then when you change back to WGS84 and HDD.MMM all should be fine. There's an interesting thing... As all OS refs are by definition OSGB datum based, is an eTrex clever enough to not translate the datum too?! Will have a play later! Quote Link to comment
+MBFace Posted June 10, 2011 Share Posted June 10, 2011 Anyone planning an ascent of Scafell Pike needs to take a paper map and compass - no batteries to run out, and even in the dark, you'll still be able to read a bit. Be sure you understand the difference between Scafell Pike (978m) and Scafell (964m) - the two tops are linked by a col called Mickledore. Wasdale Mountain Rescue Team volunteers have to guide / rescue far too many inexperienced / ill-equipped people off England's highest peak. With regards to the map and compass you forgot 'and know how to use them' - we've met far too many people on the fells with no idea. We've also witnessed a couple of inexperienced people taking the direct route from Scafell to Mickledore via Broad Stand. They made it alright but one of the rucksacks they'd chucked down first narrowly missed us as we made our way up to the col after using the Foxes Tarn route. It was a bit scary as we initially thought it was a boulder hurtling down towards us. Quote Link to comment
+Pharisee Posted June 10, 2011 Share Posted June 10, 2011 Just a thought. Take a look at http://www.walkhighlands.co.uk/ you may have to register, but it's free. They do maps, and have map/route planning. AND it's Ordnance Survey. May even have a ready-made route you can download and print. If you use their map refs, set your GPS to OS and OSGB Datum, enter map refs, then when you change back to WGS84 and HDD.MMM all should be fine. There's an interesting thing... As all OS refs are by definition OSGB datum based, is an eTrex clever enough to not translate the datum too?! Will have a play later! On most, if not all, Garmin GPSr units selecting "British Grid" in the Position Format field will automatically select "Ord Srvy GB" in the Map Datum field and vice versa... Select hddd°mm.mmm' for Position Format and WGS 84 will automatically be set in the Map Datum field. Quote Link to comment
+NattyBooshka Posted June 10, 2011 Share Posted June 10, 2011 Just a thought. Take a look at http://www.walkhighlands.co.uk/ you may have to register, but it's free. They do maps, and have map/route planning. AND it's Ordnance Survey. May even have a ready-made route you can download and print. If you use their map refs, set your GPS to OS and OSGB Datum, enter map refs, then when you change back to WGS84 and HDD.MMM all should be fine. There's an interesting thing... As all OS refs are by definition OSGB datum based, is an eTrex clever enough to not translate the datum too?! Will have a play later! On most, if not all, Garmin GPSr units selecting "British Grid" in the Position Format field will automatically select "Ord Srvy GB" in the Map Datum field and vice versa... Select hddd°mm.mmm' for Position Format and WGS 84 will automatically be set in the Map Datum field. You've spoiled my fun... thanks for saving me hours!!!! Friday evening... wine open... planning a real hard walk for the team in the morning... juste realised I'm an hour of missing my first local event back, and I'm illegal to drive! Can you set to OS and then WGS 84? Quote Link to comment
+dfx Posted June 10, 2011 Share Posted June 10, 2011 (edited) Can you set to OS and then WGS 84? I can only speak for my Oregon: When selecting British Grid as coordinate format, OSGB is automatically selected as datum and is the only choice - it's not possible to select anything else. Switching back to ddd mm.mmm format switches the datum back to WGS84. However, it's possible to select OSGB as datum for lat/long coordinates. I would assume most/all other Garmin units behave the same. Edited June 10, 2011 by dfx Quote Link to comment
+NattyBooshka Posted June 10, 2011 Share Posted June 10, 2011 Can you set to OS and then WGS 84? I can only speak for my Oregon: When selecting British Grid as coordinate format, OSGB is automatically selected as datum and is the only choice - it's not possible to select anything else. Switching back to ddd mm.mmm format switches the datum back to WGS84. However, it's possible to select OSGB as datum for lat/long coordinates. I would assume most/all other Garmin units behave the same. Thanks for that. You guys are saving me a lot of time this evening... more wine time! Quote Link to comment
+Hampk Posted June 10, 2011 Share Posted June 10, 2011 Anyone planning an ascent of Scafell Pike needs to take a paper map and compass - no batteries to run out, and even in the dark, you'll still be able to read a bit. Be sure you understand the difference between Scafell Pike (978m) and Scafell (964m) - the two tops are linked by a col called Mickledore. Wasdale Mountain Rescue Team volunteers have to guide / rescue far too many inexperienced / ill-equipped people off England's highest peak. Quite.. Heading up a major summit is definitely not a case of plugging in co-ordinates and setting off.. Map, compass, appropriate equipment/clothing - all essential items. And be sure you know how to use them! Have fun..! Quote Link to comment
+agentmancuso Posted June 11, 2011 Share Posted June 11, 2011 ... Can you set to OS and then WGS 84? No. The choice of datum relates only to the origin point of Lat/Lon coordinates. British National Grid, as used on OS maps etc, has one fixed gridpoint origin. By far the easiest way to deal with the original question is set your GPSr to BNG and enter the OS grid reference. You can switch back to lat/lon if you like, but my advice would be to leave the GPSr on the BNG setting for the duration of the walk, as that way it will be possible to relate your position on the ground to your position on the map in an instant. It's also worth pointing out that all guidebooks use BNG too. Quote Link to comment
Copepod Posted June 11, 2011 Share Posted June 11, 2011 Anyone planning an ascent of Scafell Pike needs to take a paper map and compass - no batteries to run out, and even in the dark, you'll still be able to read a bit. Be sure you understand the difference between Scafell Pike (978m) and Scafell (964m) - the two tops are linked by a col called Mickledore. Wasdale Mountain Rescue Team volunteers have to guide / rescue far too many inexperienced / ill-equipped people off England's highest peak. With regards to the map and compass you forgot 'and know how to use them' - we've met far too many people on the fells with no idea. We've also witnessed a couple of inexperienced people taking the direct route from Scafell to Mickledore via Broad Stand. They made it alright but one of the rucksacks they'd chucked down first narrowly missed us as we made our way up to the col after using the Foxes Tarn route. It was a bit scary as we initially thought it was a boulder hurtling down towards us. Yes, I admit to missing out the statement "and know how to use them" - I guess I am assuming that common sense dictates that it's not worth carrying things you can't use. I was support driver for a pair who completed Old County Tops fell race a couple of weeks ago - perfect example of how skill, experience & speed with very lightweight kit can be safe, despite very wet & windy conditions. Quote Link to comment
+MartyBartfast Posted June 11, 2011 Share Posted June 11, 2011 Just wanted to point out that the OS maps also have a scale down the side & bottom with lat & long in dd mm format ( you have to measure the decimal part yourself), which is something I hadn't noticed in ~30 years of using them until my sister pointed it out to me last year! Quote Link to comment
+lifechooser Posted June 13, 2011 Author Share Posted June 13, 2011 I think that Bing Maps used WGS84, even though it's overlaid with an OS map. I'm basing this on using Bing Maps to pinpoint caches before I go out hunting them. Thanks everyone for the advice, and just to stop you all worrying, I've got a fairly comprehensive kit list: Android phone with gvMini Maps App (gives an OS map with a "you are here" arrow). Android backup charger eTrex (will be left on to chart my ascent, as I hear that the descent is harder to navigate, and we'll be retracing our steps) 1:25,000 map, compass. 6 other people Radios Proper clothes/boots 1 person left at home who knows the route/timing 3 litre water pack Food I'm not normally allowed to eat. Optimism All we need now are more sponsors and decent weather! Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.