gps systems

GSV Three Minds in a Can

Bitstring <dh8dos$92l$1@dux.dundee.ac.uk>, from the wonderful person
Peter Clinch <p.j.clinch@dundee.ac.uk> said
>GSV Three Minds in a Can wrote:
>
>> True on =moors=, but try finding the stile from one field to the next
>>in arable/pasture land without benefit of a GPS loaded with waypoints
>>for all the ROW/field boundary intersections. No fun. None at all.
>
>Eh? Assuming you can't go in the general direction and just *look* for
>the stile for some reason, you can aim off slightly to one side until
>you intersect the boundary, then walk along the boundary to the stile.
>Orienteers do this sort of thing all the time, /and they do it for fun/.

Well they're daft then. 8>. I hate walking arbitrary lengths of hedgerow
looking for a stile which may not be there at all, and wondering if I've
gone too far yet. Even worse wandering along the bottom of a wooded
gully looking for an alleged footbridge, while trying not to fall in the
brook.

With the GPS I head straight for the proper spot, carefully scan 5-10m
each way, and if I don't find one I log an obstruction, and find the
best way through.

>> Navigating 'cultivated'/'Industrialised' areas, or in fog/whiteout
>>conditions, a compass is less use than a chocolate teapot.
>
>A chocolate teapot is very useful, because it contains a large supply
>of chocolate.

Which is why it is more use than a compass in a whiteout - you can eat
it while awaiting rescue. OK, the compass is helpful if you have some
idea where you are .. if not, you're stuffed.

> Similarly a compass in the above conditions can be very useful, which
>is how people managed with them for a long time before GPS came on the
>scene.

Nah, in cultivated / industrialised areas I KNOW which way I am facing,
and the next boundary is usually within sight. You have to work really
hard to get comprehensively lost in a wheatfield. Compass not much use
at all - I wouldn't even bother carrying one until/unless I get out on
large open commons, moors, mountains, forests, etc.

--
GSV Three Minds in a Can
Contact recommends the use of Firefox; SC recommends it at gunpoint.

Peter Clinch

GSV Three Minds in a Can wrote:

> Yes, you can use a compass, if you know exactly where you are (several
> minutes work), and exactly where the stile should be (more work,
> assuming the boundary hasn't been moved) .. really is so much easier to
> enter a waypoint on the PC and walk to it on the ground.

Too many assumptions in there. You know just as well where the stile is
meant to be whether you have a GPS or not if you're working from a map
to start with. And it's only "several minutes work" finding your
position if you have a time where you /don't/ know where you are
preceding it. The best way to navigate with map and compass is know
where you are all the time, and that's not actually difficult with
practise. I can quite understand people prefer not to put in the
practise but for those that do a GPS is /not/ significantly easier for
what you're talking about. If you find it easier for you then it'll be
easier for you, but that's not the same as an order of magnitude better
for anyone.

> I'd dispute the 'similarly easy', having tried it. You're (somewhere) in
> a field

But as above, no reason you can't pin down "somewhere" very well indeed.
For example, the fist place you'll be is at the first stile where you
get into the field, and you know /exactly/ where that is.

> the opposite side is 500m away, some distance from the RH
> corner of the far boundary is a stile .. except the RH corner may not be
> where it shows on the map, if someone took a hedge out, and the 'some
> distance' is really hard to determine from a paper map (to better than
> ~20m, which is a lot of hedge).

I don't see why you're hung up on the RH corner though. From your
current known location (the first stile) you take a bearing on the
destination stile from the map. If you take that bearing you'll
probably miss by a margin of error, but you don't know which way, so you
adjust your bearing a few degrees off to the left. When you arrive at
the hedge you know you'll be slightly off to the left, so you move right
a few meters until you find it. The RH corner has never had to come
into the operation at all. So I'm not quite sure what you tried if
you're hung up on using distant landmarks...

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net p.j.clinch@dundee.ac.uk http://www.dundee.ac.uk/~pjclinch/

Gordon

Peter Clinch <p.j.clinch@dundee.ac.uk> writes
>
>I don't see why you're hung up on the RH corner though. From your
>current known location (the first stile) you take a bearing on the
>destination stile from the map. If you take that bearing you'll
>probably miss by a margin of error, but you don't know which way, so
>you adjust your bearing a few degrees off to the left. When you arrive
>at the hedge you know you'll be slightly off to the left, so you move
>right a few meters until you find it.

LOL! This demonstrates just how inaccurate magnetic compass
navigation is - in practice, and I used the exact system when crossing
the Kinder plateau for the first time.

To sum up all these pointless arguments, GPS v Compass, if you want to
enjoy a navigation exercise take a compass, if you want to enjoy the
walk, take a GPS.

I use the map more than the GPS, but the compass stays in the sack in
case I lose the GPS and the map.
--
Gordon Harris

GSV Three Minds in a Can

Bitstring <dh8p19$g4e$1@dux.dundee.ac.uk>, from the wonderful person
Peter Clinch <p.j.clinch@dundee.ac.uk> said
<snip>
>> the opposite side is 500m away, some distance from the RH corner of
>>the far boundary is a stile .. except the RH corner may not be where
>>it shows on the map, if someone took a hedge out, and the 'some
>>distance' is really hard to determine from a paper map (to better than
>>~20m, which is a lot of hedge).
>
>I don't see why you're hung up on the RH corner though. From your
>current known location (the first stile) you take a bearing on the
>destination stile from the map. If you take that bearing you'll
>probably miss by a margin of error, but you don't know which way, so
>you adjust your bearing a few degrees off to the left. When you arrive
>at the hedge you know you'll be slightly off to the left, so you move
>right a few meters until you find it.

'A few degrees' multiplied by 500m is an awful lot of hedge away from
where you want to be (as I said), assuming you can even calculate the
required heading 'to a few degrees' in the first place (and then walk it
accurately). I can calculate to about 5 degrees, on a good day, but
whether I can walk that accurately depends on the terrain.

I've tried lots of methods, and the one that works for me, best, and
fastest, is to zoom in to about 1:1000 scale on a tracklogs 1:25k map,
place a waypoint at the field/ROW intersection, and then use the GPS to
walk to it. Takes less than 15 seconds per waypoint, works in rain snow
or fog, works if most of the terrain doesn't match the map, or if you
have to divert around a bog or herd of cows .. just works (unless the
ROW has been moved of course, or unless there really is no stile/bridge
where there should be .. although I often find the footings left over
from collapsed bridges).

--
GSV Three Minds in a Can
Contact recommends the use of Firefox; SC recommends it at gunpoint.

Roy

"GSV Three Minds in a Can" <GSV@quik.clara.co.uk> wrote in message
news:afytzcJ899NDFAdG@from.is.invalid...
> Bitstring <dh8dos$92l$1@dux.dundee.ac.uk>, from the wonderful person Peter
> Clinch <p.j.clinch@dundee.ac.uk> said
>>
>>Eh? Assuming you can't go in the general direction and just *look* for
>>the stile for some reason, you can aim off slightly to one side until you
>>intersect the boundary, then walk along the boundary to the stile.
>>Orienteers do this sort of thing all the time, /and they do it for fun/.
>
> Well they're daft then. 8>.

Er no. It actually IS fun to pick detail off a map, relate it to the
landscape using your eyes with confirmation from the compass where required.

Roy.

GSV Three Minds in a Can

Bitstring <11jg7htde91rr2d@corp.supernews.com>, from the wonderful
person Roy <roy@?.?.invalid> said
>
>"GSV Three Minds in a Can" <GSV@quik.clara.co.uk> wrote in message
>news:afytzcJ899NDFAdG@from.is.invalid...
>> Bitstring <dh8dos$92l$1@dux.dundee.ac.uk>, from the wonderful person Peter
>> Clinch <p.j.clinch@dundee.ac.uk> said
>>>
>>>Eh? Assuming you can't go in the general direction and just *look* for
>>>the stile for some reason, you can aim off slightly to one side until you
>>>intersect the boundary, then walk along the boundary to the stile.
>>>Orienteers do this sort of thing all the time, /and they do it for fun/.
>>
>> Well they're daft then. 8>.
>
>Er no. It actually IS fun to pick detail off a map, relate it to the
>landscape using your eyes with confirmation from the compass where required.

I guess YMMV .. I'm typically doing it for 5-6 hours at a stretch with
items which frequently can't be seen with eyes until you kick them (the
state of stiles/bridges in many parishes round here is somewhat short of
acceptable).

I bet some people go Geo-caching without a GPS too, right. Also probably
climb hills with one leg in a cast - anything to increase the challenge.
8>.

--
GSV Three Minds in a Can
Contact recommends the use of Firefox; SC recommends it at gunpoint.

Hilda

Go with God my friend....go with God...
through the hazardous pilgrimage of life.
Good and ill emanate from God.
We are all being tested my friend, all of us.
So take heart, you are not alone.

Peter Clinch

GSV Three Minds in a Can wrote:

> 'A few degrees' multiplied by 500m is an awful lot of hedge away from
> where you want to be (as I said), assuming you can even calculate the
> required heading 'to a few degrees' in the first place (and then walk it
> accurately). I can calculate to about 5 degrees, on a good day, but
> whether I can walk that accurately depends on the terrain.

It's not that much hedge, according to my calculator. To calculate the
heading "to a few degrees" you have a very good base bearing directly
from the map and as long as your mag variation adjustment isn't miles
off it should stay that way.

> I've tried lots of methods, and the one that works for me, best, and
> fastest

.... for you, is the way you do it now. I'm not arguing the fact, just
pointing out that compass work isn't necessarily significantly more
difficult in other hands. Judging from your worrying about distant
corners of fields and how accurately you can calculate a bearing, the
ways you've used with a compass aren't necessarily optimum or the same
as others use. I'm not saying go back to map and compass, just saying
that it won't necessarily be as awkward for /anyone/ using one as it's
proved for you.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net p.j.clinch@dundee.ac.uk http://www.dundee.ac.uk/~pjclinch/

Peter Clinch

Gordon wrote:

> LOL! This demonstrates just how inaccurate magnetic compass
> navigation is - in practice

But the point is that most of the navigation is done with the /map/.

> To sum up all these pointless arguments, GPS v Compass, if you want to
> enjoy a navigation exercise take a compass, if you want to enjoy the
> walk, take a GPS.

But what if you enjoy the walk in part because of the navigation?

> I use the map more than the GPS, but the compass stays in the sack in
> case I lose the GPS and the map.

Did a Corbett and a Munro on Sunday, cloud was in and out the whole time
over about 500m. Didn't have the GPS with me, only took the compass out
for a brief check on the top of the Munro (about 75% of the way along
the route) and again a few minutes later, then put it away.

The compass is in significant part a tool to help you use the map.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net p.j.clinch@dundee.ac.uk http://www.dundee.ac.uk/~pjclinch/

Jell

On Fri, 23 Sep 2005 11:46:39 +0100, KEITHHASLER
<keith@hasler6516.fsnet.co.uk> wrote:

>
> Im thinking of getting GPS system
> ....

Slightly OT, but ....

.... in this entire thread nobody mentions geocaching (www.geochaching.com)

I know there are hardened walkers out there who pooh pooh such frivolous
activity, but I find it is a great way to help to choose the odd
interesting route, and the children love it as a way of adding interest to
a day out. There are hundreds of caches all over the country - some in
hard terrain. (Logging one in North Wales next week that will need
climbing gear!)

And as somebody said: "I've finally found something to do with my GPS
that my wife doesn't laugh at" :-)

Back to Keith's question, I would echo many of the sentiments in this
thread. I mainly use my GPS as a track log so I can plot them on a map
later (or even better these days - on Google Earth, which I also use for
planning routes before I set out). And it is good to know it is in my bag
(usually in the top pocket of my rucksack where it gets good reception)
when the fog comes down.

For geocaching almost any GPS set will do - though the ability to upload
the coordinates makes things a bit easier.

For planning long routes I'd say that a program like GPSU is almost
essential, and it provides a link into Google Earth for showing your
friends where you went!

Jell

Jell

On Fri, 23 Sep 2005 11:46:39 +0100, KEITHHASLER
<keith@hasler6516.fsnet.co.uk> wrote:

>
> Im thinking of getting GPS system
> ....

Slightly OT, but ....

.... in this entire thread nobody mentions geocaching (www.geochaching.com)

I know there are hardened walkers out there who pooh pooh such frivolous
activity, but I find it is a great way to help to choose the odd
interesting route, and the children love it as a way of adding interest to
a day out. There are hundreds of caches all over the country - some in
hard terrain. (Logging one in North Wales next week that will need
climbing gear!)

And as somebody said: "I've finally found something to do with my GPS
that my wife doesn't laugh at" :-)

Back to Keith's question, I would echo many of the sentiments in this
thread. I mainly use my GPS as a track log so I can plot them on a map
later (or even better these days - on Google Earth, which I also use for
planning routes before I set out). And it is good to know it is in my bag
(usually in the top pocket of my rucksack where it gets good reception)
when the fog comes down.

For geocaching almost any GPS set will do - though the ability to upload
the coordinates makes things a bit easier.

For planning long routes I'd say that a program like GPSU is almost
essential, and it provides a link into Google Earth for showing your
friends where you went!

Jell

fen4b0y@yahoo.co.uk

Gordon wrote:
> To sum up all these pointless arguments, GPS v Compass, if you want to
> enjoy a navigation exercise take a compass, if you want to enjoy the
> walk, take a GPS.
>
> I use the map more than the GPS, but the compass stays in the sack in
> case I lose the GPS and the map.
> --
> Gordon Harris

Quality post.....If there was a post of the day/week/month that wins by
a country mile.

Thanks for your concise summary.......

David.

Bootlaces

On Mon, 26 Sep 2005 13:50:14 +0100
in <news:2RR5u2TG6+NDFw5r@g3snx.demon.co.uk>
Gordon <Gordon@g3snx.demon.co.uk> wrote :

> Peter Clinch <p.j.clinch@dundee.ac.uk> writes
>>
>>I don't see why you're hung up on the RH corner though. From your
>>current known location (the first stile) you take a bearing on the
>>destination stile from the map. If you take that bearing you'll
>>probably miss by a margin of error, but you don't know which way, so
>>you adjust your bearing a few degrees off to the left. When you arrive
>>at the hedge you know you'll be slightly off to the left, so you move
>>right a few meters until you find it.
>
> LOL! This demonstrates just how inaccurate magnetic compass
> navigation is - in practice, and I used the exact system when crossing
> the Kinder plateau for the first time.
>
> To sum up all these pointless arguments, GPS v Compass, if you want to
> enjoy a navigation exercise take a compass, if you want to enjoy the
> walk, take a GPS.

Illogical. If you want a navigation challenge take neither GPS, compass
nor map ;-


--
From a Cocktail lounge, Norway:
LADIES ARE REQUESTED NOT TO HAVE CHILDREN IN THE BAR

GSV Three Minds in a Can

Bitstring <dhav58$mrm$1@dux.dundee.ac.uk>, from the wonderful person
Peter Clinch <p.j.clinch@dundee.ac.uk> said
>GSV Three Minds in a Can wrote:
>
>> 'A few degrees' multiplied by 500m is an awful lot of hedge away
>>from where you want to be (as I said), assuming you can even calculate
>>the required heading 'to a few degrees' in the first place (and then
>>walk it accurately). I can calculate to about 5 degrees, on a good
>>day, but whether I can walk that accurately depends on the terrain.
>
>It's not that much hedge, according to my calculator.

I make it somewhere between 40 and 50m, which I count as 'a lot of
hedge' (or gully or whatever) when I'm searching it for a a stile or
bridge which is 1m wide.

Actually I tried it today, and the hedges were not so bad, because most
places you can walk along them looking for the stile, with a faint
chance of finding it, although one I only found through the head high
brambles because my GPS said it was there last time I walked the path.

The gullies are the killers, because if you descend in the wrong place
for the bridge (by more than a few M) you often can't get along the
bottom, you have to head back up to the field margin and try again, and
the bridges (if present, and unless new) are invisible from more than
5-10m away. Many of the streams are fordable, but if you're trying to
map the position of the FB and report its condition, you do have to
actually find it, getting across some other way doesn't hack it.

--
GSV Three Minds in a Can
Contact recommends the use of Firefox; SC recommends it at gunpoint.