Looking at GPS (Garmin eTrex)

evil-monkey

Looking at getting a GPS (considering the Garmin eTrex) but could use some feedback from anyone who has one (doesn't need to be that specific device).

How handy do people actually find these? I presume most device doesn't support national grid, so I'm right in saying that I've to convert to lat/long before entering coordinates yes? Also, once coordinates are entered, is it simply a case that I can take it out to check direction? I'd like to have it handy to check my manual bearings / direction etc every so often.

Thanks in advance for any input.

Alun

All outdoor GPS's support a multitude of national grids including Irish Grid, so don't worry on that score.

If you have a waypoint entered on the unit, you can issue a GOTO to that way point and it will show you a compass like direction display that will point you to that waypoint. You will also be able to display data fields on the same screen that show you, amongst others, distance to that WP, time (based on current avge speed), and the bearing (should you wish to transfer that to a compass). If you get a model with a built-in compass, the direction display will be active at all times, even if you're standing still. Models without a built-in compass will only show you direction if you're moving.

Remember that, unlike a compass, if you do stray off your intended path, the bearing to your destination will update to reflect this .. great for moving through areas with massive amounts of squelchy bog and peat hags

evil-monkey

Alun wrote: »

All outdoor GPS's support a multitude of national grids including Irish Grid, so don't worry on that score.

If you have a waypoint entered on the unit, you can issue a GOTO to that way point and it will show you a compass like direction display that will point you to that waypoint. You will also be able to display data fields on the same screen that show you, amongst others, distance to that WP, time (based on current avge speed), and the bearing (should you wish to transfer that to a compass). If you get a model with a built-in compass, the direction display will be active at all times, even if you're standing still. Models without a built-in compass will only show you direction if you're moving.

Remember that, unlike a compass, if you do stray off your intended path, the bearing to your destination will update to reflect this .. great for moving through areas with massive amounts of squelchy bog and peat hags

Thanks for the prompt reply! Can you recommend a model that supports OS coordinates? Would rather that to converting. Can't seem to find any info on whether or not eTrex supports.

When you say that the bearing updates - so it doesn't just point you in the direction of the coordinate, it actually suggests a best possible route?

Alun

ALL outdoor GPS's including all Garmin's models support all popular grid formats, including Irish Grid as used on OSi maps, the UK Grid as used on UK OS maps etc., so don't worry.

Although many of them can be used for routing in the same sense as car SatNav's can if supplied with maps that have routing information in them, that's not much use on top of a mountain.

So all they can really do in that situation is to work out, from the coordinates of your current position, and the coordinates of your destination what bearing you should be on. If you are navigating to a waypoint, say on an initial bearing of 120 degrees, then if you wander off that bearing, eventually the bearing display will update to show that, and the arrow on the display will start to point away from your direction of travel, indicating that you should move in such a way that the arrow is pointing straight ahead.

Think of it as a 'super-compass' that always points to your intended destination, regardless of how much you wander and deviate from your intended course.

If you're thinking of an etrex, note that the only current models Garmin sell in that series are the etrex 10, 20 and 30. If you see any other etrex models for sale they're old discontinued models. The 10 is a very basic black and white display model, the 20 has a colour screen and can take maps, and the 30 is the same as the 20 plus an electronic compass and altimeter.

evil-monkey

Alun wrote: »

ALL outdoor GPS's including all Garmin's models support all popular grid formats, including Irish Grid as used on OSi maps, the UK Grid as used on UK OS maps etc., so don't worry.

Although many of them can be used for routing in the same sense as car SatNav's can if supplied with maps that have routing information in them, that's not much use on top of a mountain.

So all they can really do in that situation is to work out, from the coordinates of your current position, and the coordinates of your destination what bearing you should be on. If you are navigating to a waypoint, say on an initial bearing of 120 degrees, then if you wander off that bearing, eventually the bearing display will update to show that, and the arrow on the display will start to point away from your direction of travel, indicating that you should move in such a way that the arrow is pointing straight ahead.

Think of it as a 'super-compass' that always points to your intended destination, regardless of how much you wander and deviate from your intended course.

If you're thinking of an etrex, note that the only current models Garmin sell in that series are the etrex 10, 20 and 30. If you see any other etrex models for sale they're old discontinued models. The 10 is a very basic black and white display model, the 20 has a colour screen and can take maps, and the 30 is the same as the 20 plus an electronic compass and altimeter.

Thanks for the advice. Looking at a 30 as the compass and altimeter are a must I think - particularly the altimeter, I find them very useful for double checking my position along my planned route.

Any particular model other than the eTrex you'd suggest?

Alun

The compass is very handy alright as you can still use it to point to your destination when you're standing still, which you can't do with the non-compass models. If you want to save some money, there's nothing stopping you from just taking the current bearing off the display, which will always be accurate whether you're moving or not, and just transferring that to a traditional compass. The compass is a 3-axis one which means that it is not sensitive at all to the position it's held in, even vertically.

The barometric altimeter is actually less useful than it sounds, as any GPS will tell you your elevation, albeit with less accuracy than your position, plus the altimeter really needs calibrating at the start of every walk which is an extra step to remember. In theory it smooths out any spikes in the GPS derived elevation, and gives a more accurate reading, especially if you've calibrated it correctly at the start.

From the etrex, you go up to the Dakota, then the Oregon and finally the Montana in the touch screen models, and you also have the GPSMAP 62 series if you prefer buttons. It's just more features really ... the ability to take memory cards, built-in cameras, wireless transfer of data, fancy geocaching apps, satnav like features etc., plus as you go up the range they get physically bigger (the Montana is HUGE) and of course much more expensive.

evil-monkey

Alun wrote: »

The compass is very handy alright as you can still use it to point to your destination when you're standing still, which you can't do with the non-compass models. If you want to save some money, there's nothing stopping you from just taking the current bearing off the display, which will always be accurate whether you're moving or not, and just transferring that to a traditional compass. The compass is a 3-axis one which means that it is not sensitive at all to the position it's held in, even vertically.

The barometric altimeter is actually less useful than it sounds, as any GPS will tell you your elevation, albeit with less accuracy than your position, plus the altimeter really needs calibrating at the start of every walk which is an extra step to remember. In theory it smooths out any spikes in the GPS derived elevation, and gives a more accurate reading, especially if you've calibrated it correctly at the start.

From the etrex, you go up to the Dakota, then the Oregon and finally the Montana in the touch screen models, and you also have the GPSMAP 62 series if you prefer buttons. It's just more features really ... the ability to take memory cards, built-in cameras, wireless transfer of data, fancy geocaching apps, satnav like features etc., plus as you go up the range they get physically bigger (the Montana is HUGE) and of course much more expensive.

Thanks again man - might spring for the eTrex 30...

micawber

evil-monkey wrote: »

Thanks again man - might spring for the eTrex 30...

If you do get the etrex 30 you can get free topo maps here
http://talkytoaster.com/ukmaps.htm

999/112

Hi Evil Monkey, The GPSMAP 62 can also be set up to show both Lat/Lng & Irish Grid simultaneously.
Alun is correct in saying that if you have to box around an object/feature, it will still point you in the right direction to your destination [waypoint].
Depending on how you set up your data fields .... the "bearing" & "heading" should both display the same numerical value to go directly to the waypoint... [Shortest distance between two points, etc.]
The 62 works well in tight valleys and tree canopy etc.
Always carry a map & compass as a backup. Have fun.:)

Alun

999/112 wrote: »

Hi Evil Monkey, The GPSMAP 62 can also be set up to show both Lat/Lng & Irish Grid simultaneously.

All the Garmin models can ... you can set up the displayed data fields to contain whatever you like out of a list as long as your arm, the GPSMAP series isn't unique in that.

Regarding working in tight tree cover, narrow canyons etc., the new etrex series and the upcoming Oregon 600 series have the advantage of also being able to receive signals from the Russian Glonass satellites. So as well as the current 32 GPS satellites, you also get an additional 24 Glonass ones. Now, due to the Glonass system being designed for use by the Russians, they have a slightly higher, i.e. more Northerly orbit than GPS, so this not only increases the potential number of visible satellites overall, but increases the chances of there being ones sufficiently high in the sky to get a decent fix when in a tight valley, especially as you travel further north.

insomnia087

When ye say Irish grid doe ye mean the old irish grid (IG) or the new irish grid (ITM)?

Alun

All current Garmin outdoor GPS's support both the 'old', but still widely used, Irish grid (IG) and the 'new', but hardly used at all, Irish Transverse Mercator grid (ITM) along with practically every grid coordinate system in use anywhere in the world today

insomnia087

Does that include the Garmin etrex 10? which is the one i'm looking at due to it's price.

thanks.

Alun

Yes!

insomnia087

Awesome cheers!

recedite

When people talk about grids and electronic compass bearings, they seem to be envisaging using the GPS to find their location on a paper map. But in practice, if the device is loaded with a map, all that is unnecessary.
Similar to when using a sat-nav in a car, after a while you find you have stopped using the road atlas. Depending on where you are, some units may have more suitable or better maps than others, which is something to consider.

TheBuck

I bought one a while back Etrex30 and although there was a learing curving to useing it as its not touchscreen ( 1st World Problems ;-) ) it turned out to be a great buy!
I used it on my Wicklow way trek and although i had a map and compass I rarely used them as it was so handy for checking my position. Once you have it loaded up and a track put in your basicly sorted.
Like all trips if you plan ahead you make it a much better experience in my view.
What are the key points that I like about the Etrex30?
1, Waterproof, I had this underwater and given a long exposure to a full stream of water from a hose. If i happen to fall in to some water im very confident it will be fine.

2, The Screen has no bother with direct sunlight in my experience, i could see everything with ease.

3, Battery life is fantastic! At east 20-25 hours on a single charge, but make sure you turn it off when not useing it .

4, You can find tons of free maps to load it up with, although I am still looking for Satellite imagery to use on it but most OSI maps that I found could be loaded on to it easy.

5, You can easily mark a waypoint for interest.

The Cons

1, It doesn't come with a lanyard or any way to clip on to your bag or shoulder strap so i bought something for it my self hand when you want to have it hanging off your shoulder strap and want a quick ref.

2, Screen can be easily scratched so be careful there or get a screen protector.

3, if your new to Garmin like i was it takes a bit of getting use to. It uses a button/rubber nipple thing to move the arrow around the screen, its not great but gets the job done.


In my next trip I think ill be taking just it and Maybe the compass with me.

Let me know if you get one!

recedite

TheBuck wrote: »

Once you have it loaded up and a track put in your basicly sorted.

What you are doing there is downloading the exact route as recorded and uploaded by someone else (previously) on their unit, and then following that same route on your own unit.
Handy for something like the Wicklow Way, although that sort of fixed route is usually well signposted on the ground anyway.

To get the full potential out of these units, you want to be able to see a screen showing your exact position as a moving cursor, superimposed on the best available map for the particular area you are in. Then you have the freedom to detour off the fixed route, or go your own route.

The ideal unit would be one that can be loaded with different local and highly detailed maps, and then utilises Glonass as well as GPS satellites to determine your position on the chosen map.