best bushwalking GPS?

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best bushwalking GPS?

Postby tigercat » Thu 18 Dec, 2014 3:08 pm

Need to replace my old etrek, any suggestions?
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Re: best bushwalking GPS?

Postby tastrax » Thu 18 Dec, 2014 8:19 pm

Another Etrex if you just want something small - 20 will take maps, 30 has the compass that works while stationary (if I remember correctly). Both have heaps more storage than the older models. Still great battery life.

Compare them here

https://buy.garmin.com/en-AU/AU/catalog ... duct=87774
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Re: best bushwalking GPS?

Postby keithy » Fri 19 Dec, 2014 10:46 am

As tastrax posted, if you're comfortable with Garmin, I don't think you can go wrong with the Etrex 20/30. Much nicer if you're stepping up from the old b&w eTrex series.

And if step up to the more advanced Garmin models like the Oregon 600 series or Montana series the main benefits are:
* a larger touch screen, which is easier for navigating around the map screen compared with the joystick or buttons and
* faster processor, so it speeds things up if you have big maps redrawing.

The downsides with fancier models are:
* the price,
* the increased size/weight,
* and the shortened battery life.

Of course, you could go to the GPSMap series but I found that going from the eTrex 30 to the big unit with the quad helix antenna was hard to do, so went with the smaller units with internal antennas.

I love my eTrex 30 - it is only about 170g with two batteries, and 2 x Eneloop batteries lasts about 20 hours for me. But having gone to the Oregon 600 with it's touch screen, I find it hard to go back to the eTrex. The downsides are the battery life - I get only about 10hrs or so with the Oregon, and the Oregon weighs more 215g with two batteries.

The internal antennas on both my eTrex and Oregon models don' t seem to slow it down satellite reception when compared with my very old 60cs with external antenna. I find the Oregon seems to be a smidge quicker than the eTrex.

And I am a little biased in coming from being a long time Garmin user. I tried Magellan once, but didn't get used to the Menu system, and at the time there weren't free maps offered with the Magellan.

But there have been previous posts on Garmin/Magellan, especially for Tassie users. Like these:

viewtopic.php?f=21&t=10279
viewtopic.php?f=21&t=10151

Also at the time I looked at the Magellan unit, they couldn't do custom (raster/scanned) maps like the Garmins could, although now Magellan can do this in the Triton range. But I would caution that the Triton range doesn't have the best reviews though:

http://www.amazon.com/gp/product/B000V4VGAI
http://www.amazon.com/gp/product/B000V4S6Y2
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Re: best bushwalking GPS?

Postby Strider » Fri 19 Dec, 2014 11:33 am

I've noticed there is a significant price difference between the ETrex 20 and ETrex 30. Is it justified? The functionality differences seem minimal?
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Re: best bushwalking GPS?

Postby keithy » Fri 19 Dec, 2014 11:53 am

Strider wrote:I've noticed there is a significant price difference between the ETrex 20 and ETrex 30. Is it justified? The functionality differences seem minimal?

When I got my eTrex 30, I think the price difference was around $100, but I've seen that come down recently.

The only substantial differences are:

    * the Tri-axial electronic compass - so the compass points in the correct direction even when stationary
    * barometric altimeter
    * wireless data transfer - this is only to compatible Garmin units, not wireless to PC

So if you wouldn't use those functions, you're probably better off going the cheaper eTrex 20.

I use the electronic compass and quite like it, although with some earlier firmwares it was a bit buggy and the calibration went weird. Also use the barometric altimeter a bit and it is handy to also display the ambient pressure.

I have only used the wireless data transfer once, when I had created a route on the eTrex 30, and transferred it to the Oregon 600. It would be handy if you have created a route, and have others in your bushwalking party that also have Garmin handhelds and you can share the same route.
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Re: best bushwalking GPS?

Postby photohiker » Fri 19 Dec, 2014 12:40 pm

I carry a real compass, and really the barometer stuff has never been much use to me. Both functions consume battery power so when I upgraded from the Etrex Hcx I dropped those two features and bought the 20. Happy with that unit, recommended.
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Re: best bushwalking GPS?

Postby Zone-5 » Tue 10 Feb, 2015 2:12 am

Both are used while hiking. The etrex 20 lives in the pack (ON) while the older and less confusing Etrex 'H' gets to go with me in the hand...

Image

;)
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Re: best bushwalking GPS?

Postby Strider » Tue 10 Feb, 2015 6:57 pm

Where are those prices from Zone-5?
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Re: best bushwalking GPS?

Postby skog » Tue 10 Feb, 2015 7:20 pm

Strider wrote:Where are those prices from Zone-5?


I was wondering the same thing :wink:
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Re: best bushwalking GPS?

Postby Zone-5 » Wed 11 Feb, 2015 1:55 am

skog wrote:
Strider wrote:Where are those prices from Zone-5?


I was wondering the same thing :wink:


Sorry guys it was the only pic I had on hand...

viewtopic.php?f=27&t=12671#p212157

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Re: best bushwalking GPS?

Postby keithy » Wed 11 Feb, 2015 4:59 pm

Zone-5 wrote:Sorry guys it was the only pic I had on hand...
viewtopic.php?f=27&t=12671#p212157

The venerable Etrex yellow was a great cheap unit in it's day but I thought they were long discontinued? I noticed from the thread you linked to you got yours recently (well, 2013 recently)?

When you got yours, were they still shipping without cables? That is one of the most annoying thing I found about the eTrex yellow. The stupid proprietary serial cable connection - and the fact it didn't come with the unit and had to be bought separately. Meaning you couldn't easily transfer routes and waypoints from a PC to the GPS.
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Re: best bushwalking GPS?

Postby dnaylor » Wed 11 Feb, 2015 7:21 pm

Just wondering... if you have a decent smart phone with GPS capabilities why not use an app called "Maverick" i currently use this and it doesn't tie you to one map system... a mobile that has removable batteries is a plus though as constant GPS usage drains them fast, need to be aware though that most mobile based GPS systems also tend to update maps on the fly via mobile coms so if going to be in a no or dodgy signal area do a walk through the trip on Maverick while you have good signal and it will cache the maps... had my samsung in "flight mode" while on a flight back from HK to Sydney once, my maverick program was running and matching everything the flight info screen cathay was showing...
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Re: best bushwalking GPS?

Postby highercountry » Wed 11 Feb, 2015 7:26 pm

keithy wrote:Just wondering... if you have a decent smart phone with GPS capabilities why not use an app called "Maverick" ...


You answered your own question on why not to use a mobile phone GPS.
Limited battery life, pure and simple.
There are some excellent mapping Apps around these days. One of the best is Mapout. Really good detail and brilliant 3D images on latest model iPhones and iPads. http://mapout.ch/en/
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Re: best bushwalking GPS?

Postby Mark F » Wed 11 Feb, 2015 8:43 pm

Personally I have been trialing NSW lpi topopdf maps with PDF Maps software on a Samsung Galaxy S4. Overall I am very happy with this system. Combined with an Anker 5200mAH power bank (150 g) and a spare battery (38 g) I can go over a week without recharging and have sufficient power to keep my phone, Steripen Freedom and Petzl Tikka XP with Core battery fully operational. I set the phone in plane mode and I am NOT trying to create routes, just check the map and my position as required but fairly frequently and occasionally follow a preloaded route. I should note that I always have a printed copy of the map and a compass.
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Re: best bushwalking GPS?

Postby keithy » Wed 11 Feb, 2015 10:02 pm

highercountry wrote:You answered your own question on why not to use a mobile phone GPS.


I don't think you meant to quote me? I didn't ask that question in your post.

But, horses for courses IMHO. I find the GPS in smartphones great for geocaching and stuff around town, and as a backup when bushwalking.

Smartphones have gotten better GPS chipsets now, and some newer models have integrated chipsets into their SoCs. I compared a few phones I had a while back with my Garmin GPSs, as well as with my other GPS devices.

For example, when I compared my old Garmin GPSmap 60 running a SirF Star III GPS and an Asus Windows Mobile Based GPS (A696) which also sported the same GPS chipset, I found that the acquisition times, and the GPS drift worse in the Asus. I thought it might have to do with the internal antennal of the Asus, so I added an MCX external GPS antenna to the Asus. Attached the external antenna to a hiking pole sticking out of my backpack, and found it improved initial startup acquisition, but still had issues with the GPS drift.

More recently I've compared gpx logs taken from my Etrex 30 with the GPS on Nokia phones and Sony Xperia Android smartphones (not sure what GPS chips they use), as well as an iPhone 3GS and iPhone 4. I think the iPhone used to have a separate Broadcom GPS chipset (BCM4750), but have moved to an all in one baseband chipset (a Qualcomm for the 4 at least) - I don't know what they are using in the 5 or 6.

Anyway, from my tests, all phones were run with GPS only (sim cards removed) and only track recording started only when signal acquisition was achieved on all devices. On the Nokias and Android, I was mainly using Sporttracker to save and export gpx files, but have a variety of different apps that can do this. For iPhone I was having some issues wth Sporttracker for iOs, so went with another app that logged tracks.

What I found was that the smartphones I used, all using the onboard GPS only, tended to vary significantly in total track distance after a walk. So I compared the gpx files and found that on the phones I tested, the slower I walked, the more drift there seemed to be in the GPS logging, resulting in some fairly bloated total distances. From memory it could mean an extra km every 4-5kms.

I can't find the original gpx files (might be on an old PC or on a HDD somewhere), but I have this screenshot comparison that I uploaded to another forum. This one shows the track saved from my eTrex 30 (blue) compared with the track saved from the Nokia's GPS chipset (red). The more pronounced differences were on the uphill sections where I was walking slower, but it could have also been from the tree cover. Either way, it showed a definite descrepancy which resulted in very inaccurate data at the end of the walk.

GPS Sports track dandenong ranges.jpg

My newer Oregon 600 runs an STM Cartesio GPS chipset and and I believe has the same internal ceramic antenna patch that the etrex has. I haven't done significant gpx log testing between them yet, but will get around to it soon.

I haven't opened up either my Garmins, but for those curious, Gough Lui has done a tear down of the Etrex 10 http://goughlui.com/2014/05/24/quick-re ... dheld-gps/ You can see the ceramic internal antenna that is used - it is the white square with "100" printed on it, above the LCD screen. It is a similar antenna for the Oregon series. In addition to the differences in the GPS chipsets, smartphones can use different internal antennas for the GPS, which have obvious implications for the GPS reception. I think the iphone 3GS was a small antenna at the top, while the iphone 4 shared the same antenna for GPS and Wifi.
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Re: best bushwalking GPS?

Postby Walking_addict » Thu 12 Feb, 2015 12:32 am

highercountry wrote:There are some excellent mapping Apps around these days. One of the best is Mapout. Really good detail and brilliant 3D images on latest model iPhones and iPads. http://mapout.ch/en/


Thanks, just got this and looks sweet, plenty of detail for driving and walking with most walking tracks.



Sent from my iPhone using Tapatalk
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Re: best bushwalking GPS?

Postby Zone-5 » Thu 12 Feb, 2015 1:53 am

keithy wrote:The venerable Etrex yellow was a great cheap unit in it's day but I thought they were long discontinued? I noticed from the thread you linked to you got yours recently (well, 2013 recently)?

When you got yours, were they still shipping without cables? That is one of the most annoying thing I found about the eTrex yellow. The stupid proprietary serial cable connection - and the fact it didn't come with the unit and had to be bought separately. Meaning you couldn't easily transfer routes and waypoints from a PC to the GPS.


NoPe! :x

But you can easily make your own...

ImageImage

http://etrex.webz.cz/hard.html
http://pfranc.com/projects/e2Plug/index.htm
http://www.jens-seiler.de/etrex/datacable.html
http://www.pfranc.com/projects/g45contr ... /index.htm
http://www.tramsoft.ch/gps/garmin_etrex-h_en.html

:mrgreen:
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Re: best bushwalking GPS?

Postby Zone-5 » Thu 12 Feb, 2015 2:15 am

Looking for one of these...

Image

Oh yeah... 8)
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Re: best bushwalking GPS?

Postby icefest » Thu 12 Feb, 2015 6:21 am

The first GPS I used was this:
Image

With the larger part of my learning beiong done on this:
Image

I still think the etrex 30's battery life and temperature sensor ability makes it the best.
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Re: best bushwalking GPS?

Postby Zone-5 » Sun 15 Feb, 2015 1:06 am

Standard equipment for solo hikes...

Image

...perhaps a personal EPIRB would be better?

What do you think?

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Re: best bushwalking GPS?

Postby photohiker » Sun 15 Feb, 2015 1:46 pm

I use the Etrex 20 and the original inReach. I also carry a switched off smartphone which can be used as an emergency navigation device and communication when within range. I can't really see the value of the Spot with the inReach. I'd probably drop the Spot and if I really wanted more emergency comms than the inReach offers, go with a PLB.
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Re: best bushwalking GPS?

Postby skog » Sun 15 Feb, 2015 6:40 pm

I wanted to say and big thanks for the information on GPS. I went out yesterday and brought a Garmin etrex 30. Ray's price matched it for $299 and included topo maps of Oz and NZ.

It was a great piece of equipment today and I'm glad that I brought one :D
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Re: best bushwalking GPS?

Postby keithy » Sun 15 Feb, 2015 7:59 pm

skog wrote: I went out yesterday and brought a Garmin etrex 30. Ray's price matched it for $299 and included topo maps of Oz and NZ.


Nice. It's a good device. I use mine now with an ANT+ heart rate monitor for runs as well. Did you get the prebundled topo kit with V4 topo maps? Or did they throw in the V5 topo maps?

Anyway, here are some tips for your new toy.

  • Update the firmware. The 4.20 was released just recently. My original firmware when I got my etrex 30 had some bugs that impacted utility.
  • Put your details on it - edit the startup.txt file. More info here: viewtopic.php?f=21&t=16041
  • use a screen protector to save the plastic screen from scrapes. I use a DIY cutout template and make them from $1 ipad screen protectors from eBay.
  • make a DIY "bumper" case from an old mountain bike inner tube - I got the idea from this guy's blog http://www.takeadventure.com/images/sto ... ection.jpg
  • some eTrex seem to be fussy with certain Mini USB cables when plugged into a PC. If a cable plugged into PC shows it to be providing external power supply and not connecting in PC mode, try another cable.
  • Belt clip - I've found after using various cases for my Etex, that the belt clip https://www.ja-gps.com.au/Garmin/etrex- ... belt-clip/ is awesome. I use it almost all the time, together with a lanyard strap as a secondary secure point.
  • turn off WAAS/EGNOS in the setup if it is on. We don't have an augmentation system in Aust yet, and it might decrease your accuracy if enabled and uses more slightly battery when on. But if you travel to the US (WAAS) or Europe (EGNOS) you can turn it on .
  • The up/down keys on the LHS will actually act as Page Up/Page Down keys in the Menu system, to make it quicker in navigating menus.
  • A quick way to save a waypoint is to hold down the joystick button, followed by a second press for "Done". It will automatically name the waypoint in numerical sequence, and you don't have to go through the menu system.
  • An annoying thing about the joystick though is the potential for accidental presses, especially if you use a case. You can mitigate this somewhat by using a "corn plaster" around the joystick. I use an adhesive foam pad from a craft store that I cutout into a small donut shape and put that around the joystick.

And regarding the firmware updating, normally use Garmin Express, but if you are like me and have Garmin Express not working well with your PCs, there is a manual way of updating firmware using the file directly downloaded from Garmin:

The file naming convention and location from Garmin is download.garmin​.com/software/eTrex20_30_Webupdater__420.gcd (you can replace the numbers with the latest ones - the "420" that is)

- Download Firmware GCD file from Garmin
- Copy file to device \Garmin directory
- Rename file GUPDATE.GCD
- Disconnect Device from PC
- Make sure you have full battery power
- Reboot and it should confirm the firmware update
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Re: best bushwalking GPS?

Postby Zone-5 » Sun 15 Feb, 2015 9:15 pm

I'm still on a very stable 3.90, so what difference with 4.20 if any???

I've got an Etrex 20 but for a while I have been running and version of the firmware made for the Etrex 30 but will run on the 20 giving the 20 all the software extras that the 30 has, cool eh!

I can give you the links as it's not hacker ware just a different OS conversion and it's free to use..

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Re: best bushwalking GPS?

Postby Zone-5 » Mon 16 Feb, 2015 12:32 am

keithy wrote:
The file naming convention and location from Garmin is download.garmin​.com/software/eTrex20_30_Webupdater__420.gcd (you can replace the numbers with the latest ones - the "420" that is)

- Download Firmware GCD file from Garmin
- Copy file to device \Garmin directory
- Rename file GUPDATE.GCD
- Disconnect Device from PC
- Make sure you have full battery power
- Reboot and it should confirm the firmware update


Got update from this source ...

http://www.navigation-professionell.de/ ... e/#etrex30

...and did the manual update as suggested above. All went well and a lot quicker than by the Communicator plugin!

Image

Thanks


:mrgreen:
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Re: best bushwalking GPS?

Postby photohiker » Mon 16 Feb, 2015 6:18 am

What are these software extras you speak of ?

The linked updater says Etrex 20/30, are you saying this is actually the Etrex 30 updater?
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Re: best bushwalking GPS?

Postby keithy » Mon 16 Feb, 2015 10:49 am

Zone-5 wrote:I'm still on a very stable 3.90, so what difference with 4.20 if any???

I can't recall, but I think from 3.90 most of the small changes were fixes or improvements for Etrex 30 issues like the external ANT+ sensor use/barometer.

And there was an issue with saved tracks when viewing the saved track gave different information than viewing the track on the dashboard. But there is still something broken when I save a portion of a Current Track. Viewing the saved track via Track manager, there is still data statistics that are not displayed for the saved track (time/moving average/calories). Saving the whole track displays the data correctly.

Zone-5 wrote:Got update from this source ...

You don't need third party sources for the firmware, you can get it directly from Garmins' download server - download.garmin​.com/software/ . Except if you want older firmware, of course. Garmin used to keep all their old firmware on the server, and it was still downloadable manually, but maybe a year or two ago, they started only keeping the current firmware in that directory on the server, so made it more difficult to downgrade firmwares if there were issues with newer releases.

photohiker wrote:What are these software extras you speak of ?The linked updater says Etrex 20/30, are you saying this is actually the Etrex 30 updater?

It's a combined firmware, but the features for Etrex 30s are not installed on Etrex 20 devices. Not sure I see the point of the Etrex 30 portion of the firmware running on an Etrex 20 though, given the missing hardware sensors (electronic compass, ANT+ sensors, barometer). Well, maybe for the elevation plot dashboard - I think that dashboard is not visible on the Etrex 20.
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Re: best bushwalking GPS?

Postby Zone-5 » Mon 16 Feb, 2015 11:52 am

photohiker wrote:What are these software extras you speak of ?

The linked updater says Etrex 20/30, are you saying this is actually the Etrex 30 updater?


No. The updater is for both 20 & 30.

What I'm saying is the base firmware are different, The updates are selective to the base firmware they are applied to.

I am more than happy to give a link for an adapted firmware to try that gives you all of the features that the 30 has which the 20 does not.
That being the firmware will access the extra ascent and decent elevation plot and 'point & move to' features of the 30 with more options with graphics and trip planning but because the hardware (picture) is missing on the 20 which the 30 has, some of the extra features will not work obviously...

Here are the physical differences between the Etrex 20 & 30, can you see what's missing on the 20?

-----------------

This is a comparison of the PCB of the two models of Garmin GPS Etrex 20 and 30.
As you can see, the Model 20 has none of the sensors that are in version 30.
That is why the 20>30 firmware does not work exactly like a etrex 30.
If anyone WANT add I think only the barometric sensor is easy to solder.

Furthermore you can see in the last picture the 3 main chips used in these models.

    CPU: STA8088EXG
    2GB Memory: Samsung KLM2G1DEHE-B101 This memory can have two configurable boot. 'Region 5 - Boot Block' and 'region 12- Boot.bin'
    256kb Memory: K5N5629ATA [NOR 256Mb] Could this be the NV?
    Combining KLM2G1DEHE-B101 + K5N5629ATA [NOR 256Mb] is widely used in some mobile phones, so maybe you could read and write these memories with some software used in phones.


Image

I might eventually solder on the BARO chip onto my 20 and run this modified 30 firmware on my 20 permanently to access the elevation features!

BUT...

"I've often found that the GPS companies (when talking about non aviation devices) have little understanding of the proper terminology differences between altitude and elevation. And even when they do understand the differences in the manual the GPS is often doing something different.

And from talking from a few GPS programmers, it is even more confusing since I've been told they often look at how "good" of a constellation they have for calculating altitude (actual positions of satellites, not just how many they are hearing) and then try to adjust how much they want to try to augment the calculation with what they are getting from the barometer.

In short... it's messy and don't ever trust the altitude reading from any GPS unless it is specifically designed for aviation and pilot approved."


For walking it's OK but for aviation, no!


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Re: best bushwalking GPS?

Postby Zone-5 » Mon 16 Feb, 2015 12:28 pm

Image

If anyone is interested in understanding the real workings of Garmin GPS devices, then there is an advanced online manual ( although model outdated) page that explains all the bits that are wholly missing from Garmin's own site , literature and manuals. I read this entire site and was amazed at the detailed explanations and relieved that I had because no where else does it really explain how to master your Garmin GPS device intellectually. The information is universal to all GPS devices, brands and models but it does cover the foundation ethos that Garmin used in it's products. It does not really cover the advanced features specifics for feature sake but covers the principal understandings & reasons that underpin those features and how better to use them with regard to navigation.

...make of it what you wish, but like me someone will get a lot from it... enjoy!

http://www.gpsinformation.org/dale/wgarmin.htm

Update info's here...

http://gpsinformation.net

:)
... moved to another forum @ 10/10/2015
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Zone-5
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Re: best bushwalking GPS?

Postby keithy » Mon 16 Feb, 2015 9:36 pm

Zone-5 wrote:"I've often found that the GPS companies (when talking about non aviation devices) have little understanding of the proper terminology differences between altitude and elevation. And even when they do understand the differences in the manual the GPS is often doing something different....


Zone-5 - Out of curiousity, where is the quote you are making from?

I have had the opportunity to compare altitude data from my eTrex 30 with a couple of Garmin aviation GPS devices (GPSmap 495, and Aera 550). See both on the flight deck in this blurry pic.
GarminAera550GPSMap495RS.jpg

A close up of the Aera550 in action.
Garmin Aera550RS.jpg
Garmin Aera550RS.jpg (181.22 KiB) Viewed 31589 times

The altitude in the Aera550 is the geometric height above MSL and was within cooee of the reading from my eTrex 30 on a non-pressurised turboprop aircraft (between about 10-15m). There was some variation in the altitude from both GPS devices compared with the altitude displayed on the aircraft's altimeter for obvious reasons. But still, pretty good for a handheld GPS IMHO. I haven't had the opportunity to compare my Oregon ones with aviation GPS units though.

Getting back on topic, I've noticed on using a GPS that uses a barometer to adjust the elevation, is that when the weather changes quickly, it results in differences in the elevation data reported, if you don't recalibrate the elevation.

For example, this was noticeable when I did the walk from Gorek shep to Everest Base Camp with my eTrex 30.

You can see from the elevation chart here:
08 Gorek Shep to Everest Base Camp Return.jpg
08 Gorek Shep to Everest Base Camp Return.jpg (51.59 KiB) Viewed 31589 times

The elevation chart should be a mirror image, but as you can see here there is a 8m to 11m
elevation difference at various points. I didn't recalibrate the elevation at base camp, so when the weather changed and got cooler, it appears the algorithm used assumed I was going higher and adjusted the elevation higher. I assume if I had turned off the barometer, it would have used geometric elevation alone, like the eTrex 20 does, or if I had recalibrated the barometer when the weather changed it would be more accurate. Still, going through the gpx data I found at worse it was around 11m out.
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