Hema Navigator?????

Thanks Scooby. Am I correct in sauing that when it's in the car it is being constantly charged. The problem you have had is only when it's being stored??

Yes joff 1 you are correct, when in the car it is being charged. My cigarette lighter plug is wired to be on all the time so that when I turn the engine off the navigator is still running off the car. When on a trip I often leave the Navigator on all night as it draws so little power and allows a quick startup in the morning as it is already locked onto satellites.
Scooby

Gday Joff1,
I have one of those Hema navigators, have not used it a lot but it seems pretty good, also good with street nav.
I believe that if you just switch it off it hibernates, and can quickly restart, but uses the battery, if you are storing it shut down the application first the same as you would a laptop.

HUH?

Seems I need to do some googling LOL

How does the computer locate you???

Hi Warstar
You connect the laptop via a GPS or GPS Mouse. The hole package even if you started from scratch, is well under the $999 asking price for the Navigator and will let you do far more tasks.

Cheers and Seasons Greetings

Stephen

Hi Doug

Bought my 760 today. Lovely unit.


Peter

Peter
Good one mate.... pop into my gps webpage and check out the helpful hints on how to gain some extra memory in the unit, read it and if you do it make sure you dot the I's and X the T's .

The Website

.

ummm..no Doug - your Nuvi is displaying contours not "ends of dunes".

What is being discussed is this ..

Image Could Not Be Found

Image is from 250K Natmap of close on same area you posted and is the same as the 250K map supplied on Hema Navigator (though there are other less detailed maps as well).

The lines represent the extent of each dune.

As you can see (but probably wont admit) the 250K map shows the extent of dunes whereas the oztopo map you have posted from your Nuvi does not, it just shows 10m contours which, even at that scale are too broad to identify individual dunes in this area

Also keep in mind the data used to create the contours for oztopo is based on 90m spaced spot heights so narrow dunes will not rate a mention.

It would be difficult (but not impossible) to show relatively subtle dunes by way of contour lines but it would require a high level of survey plus a lot of lines cluttering up the screen...plus when does a dune stop, and when does it start (based on contours).

In this instance suspect the map makers have just traced the extent of dunes using stereoscopic air photos - and thereby where "dunes" stop and start is obvious based on human eye (and that is what is shown on the 250K map). Based on experience even the 250K mapping is pretty accurate in this respect.

Cheers
Greg

Correct me if I am wrong but couldn't you purchase the Hema 250k maps and load them on the 760 and get the same image?

Lord Cochrane
You have been corrected...... WRONG

.

Greg
And yours is showng silly lines......not dunes , perhaps we better go google earth,

.

Folks,
I did spend a fair bit of my time generating the contours in areas of Australia for the NATMAP series of maps. They were plotted at 1:100k with 20 metre contour intervals with the with the 50 metre contour being captured for the 1:250K maps which were derived from 1:100k compilations. The 1:100 compilations now only exist in the the archives for a significant part of Australia especially in the desert areas. Plotting contours in sand ridge country is difficult and we made no attempt to plot individual sand ridges. We were required to plot the general shape of the terrain ignoring sand ridges (using the valley between ridges as the terrain surface) and placed spot heights on top and the bottom of many sand ridges to indicate the height of the ridge. The sand ridges were plotted as separate features as accurately as possible and almost every sand ridge that fitted our minimum length criteria was plotted. In the old series of 250k maps (PRE 1997)the sand ridges were depicted as plotted and you could navigate by them from the air or on the ground.

In the current series of NATMAP 250k maps (post 1997)and digital maps I would be very careful trying to use sand ridge information to navigate with, as some enthusiastic some public servants took the decision to "tidy up" the sand ridge patterns in areas where they "looked very messy and fragmented" so they would look neater on the maps". They did this by removing sand ridges from the maps to make the map look more aesthetically pleasing to the eye. We did protest the decision but lost out. Our point that taking sand ridges off the maps didn't mean they ceased to exist on the ground was ignored.

The moral of the story is don't trust the sand ridge depiction on the 250k NATMAP maps after 1997 in central Australia. Hema used the base data from the NATMAP Series maps and added their own researched data , so be careful with them too but I suspect they used the original data and I am not sure if they updated to the "generalised version from NATMAP post 1997.

So Doug is right in saying if you want to see a true representation of the sand ridge patterns and extents, go to Google Earth.

Identifying sand ridges from contours where the sand ridges are contoured would be very difficult in my opinion (ie the crests of sand ridges). I haven't yet see the Oztopo maps so I can comment on them specifically.

Toolman

"And yours is showng silly lines......not dunes,"

No Doug, it is the "silly lines" in Oztopo dont show dune ridges, they are contours.

The 250K map legend specifically states that the lines represent sandridges.


Image Could Not Be Found


They are not randomly generated "silly lines", though I suppose to some they may appear to be just that.

Cheers
Greg

Hello again

We have sort of gone off track. Point of my post was to illustrate what was being discussed in the original thread re sandridges being depicted on maps i.e. the 250K map available on the Hema Navigator that shows dunes ridges. I think I got that right.

Doug incorrectly pointed out that the Oztopo maps, when displayed on the greatest GPS in the world, show the same thing, they dont. They just show 10m contours, not sandridges/dunes.

The "silly lines" do in fact represent dune ridges despite Doug’s claim they don’t. How accurate this depiction is, is another question and would vary from location to location. I personally haven’t checked every sand dune in the deserts against the 250K map series but the ones I have seen were “pretty” accurate as I stated before (don’t ask me what pretty accurate means:). Also keep in mind it is a 250K maps so there is a limitation on the detail that can be shown. It would not be possible to show every single dune present in some areas. The smaller scale Hema maps lack even more detail with respect to sandridges.

Of course if you want to see a true representation of the dunes looking at an air photo/sat image is the best option (next to actually driving there) but that wasn’t the question being asked or the point of the post. However, the funny thing about that line of thought, going back to the original discussion, is that you could also view calibrated air photo/sat image images on a Hema Navigator via OziExplorer.....so if you want to see sandridges – get a Hema Navigator (or similar device that has a program such as OziExplorer that allows viewing of calibrated air photos/sat images).

Cheers
Greg

Hello

Below is the sat image for the same area previously depicted with the sandridges (or "silly lines") taken from the 250K maps overlain. This illustrates that the lines depicted on the 250K maps are in fact depicting sandridges and aren’t as silly as some think (you have to laugh dont you). Also shows, in this area at least, that the number of sandridges depicted is high, so doubt cast by Toolman in respect to this may be slightly unfounded (i.e. don’t think sandridges have been "tidied up" too much in this area, if at all).


Image Could Not Be Found


Accuracy varies but I would still call it pretty good (keeping in mind it is 250K data and inaccuracies in my calibration of the sat image). Whether or not the depiction of sandridges in this manner (ie on a 250K map) is useful/fraught with potential problems when used in a real world situation is another question and would be dependent on intended use/aim of those using the info. Certainly better than nothing.

Cheers
Greg

Greg,
Just to clarify what I was saying.

The areas I am talking about were where the sand ridges were short and did not follow any specific pattern or direction. For an example of the type of area, refer to (Simpson Desert Nth) coords 24.8112S & 132.6334 E. I am not saying that 5this area specifically was tidied up but that was the type of area that was tampered with and in those areas the sand ridge patterns are not an accurate depiction of what exists on the ground. The sand ridges shown are accurate position wise , but not all sand ridges were kept, which to me was unfortunate. I could go though my records and find out specifically which map area's we tidied up but that but that would be a long job and it really isn't all that important. When the names come back to me I'll let you know.

The area you have depicted above is not what I would call a confused sand ridge pattern and would therefore not have been touched. I am not surprised they are relatively accurate. We took a lot of care plotting them.

What I am interested in is how you overlayed the image and the map so professionally.

Toolam

Hello

No worries – sounds like a painful job plotting all them – far out! There’s one or two to do!!

Anyway what I did...

Screen capture from GE. Calibrated in OziExplorer by using identifiable points with coordinate read out from GE. Think I used 4 points.

Downloaded Geoscience Australia 250K map data for the area (Pandie Pandie map sheet) in arcview shapefile format (from GA website). Looked for a file called silly_ lines.shp but couldn’t find it so used one called sandridges.shp instead.

Imported this into OziExplorer (using import shapefile function) – Bingo sandridges overlain on GE photo. Saved it as an OziExplorer track file and change line type to red dashed. Exported image as PNG using OE, then saved as jpg (800 pixels size) in image editing program.

I could have also imported the shape file and then saved it as a kml file using OziExplorer and displayed it directly in GE. This would have eliminated the need to calibrate the screen capture..but I only just thought of that option.

Cheers
Greg

How much would the dunes have moved in 11 years ?

Mike,
The sand ridges were plotted anything up to 35-40 years ago and none would have been added from about 1980s onwards when the maps were completed for the first time. Since then they have just been revised for cultural changes mostly - (roads & tracks, bores, mills tanks/dams fences, buildings, power lines microwave towers etc). The sand ridges would be 99.9% from the original plots. I couldn't tell you how far the sand ridges have moved but you could find out by referring to the original aerial photography and comparing that to google earth.

I suppose you are aware that the sand ridges move along their length not like waves in the ocean and the lines reflect the direction of the prevailing winds.

Toolman

"I suppose you are aware that the sand ridges move along their length not like waves in the ocean and the lines reflect the direction of the prevailing winds. "

- I learn so much from Exploroz Forums !

Thanks

Hello Lord Cochrane (SA)

RE: Statement "Correct me if I am wrong but couldn't you purchase the Hema 250k maps and load them on the 760 and get the same image?"

Sorry for late reply but further to Doug's response (which was technically correct) it is actually possible to show the same data but it must be in a different format. The Hema and Natmap maps used by the Hema Navigator are in raster format whereas Nuvis required data in Garmin specific vector format.

The free "shonkymaps" has included some of the sandridge data in its map set but not all. As Doug illustrated the OztopoV2 maps don’t.

Image Could Not Be Found

Oztopo crew could have included the data, but they chose not to presumably because of the amount of data required and corresponding increases in file size and maybe screen clutter?? If you are keen it is relatively easy to make your own Garmin maps, so if you had a specific requirement to use a Garmin and needed the data you could do it.

Cheers
Greg

Hi,
From your comments it sounds like you are using the route66 street navigation in a remote area where it is really only meant for turn by turn instructions in built up areas.
You would be better off using Oziexplorer or Memory map applications which are much more suitable to country and remote areas, all three application would be loaded if you have recently bought it.
They are moving map displays and are very detailed, especially Oziexplorer but will not give you navigation instructions, merely your position on the map, you can plot tracks and distances to waypoints though.
I find it's easier to have a paper map to refer to as well, the GPS gives you a very detailed view of your immediate area, say a few kilometers across,great for finding tracks and waterholes etc, and the paper map for the big picture.
Once you get the hang of it it's really quite easy to use.


Cheers, have fun

Hell - Have you tried the explorist vista driver?

Explorist vista driver for NMEA output

(dowload link for the driver is at the bottom end of abovementioned webpage)

I dont think you can use the Hema navigaor to provide NMEA data to a PC. OziExplorer works with Vista. Possibly better off getting a cheap gps mouse (<$100) when you want to use a laptop.

Cheers
Greg

PS - there are cheaper (~1/3 price) alternatives to Hema Navigator (HN) that do the same thing. I run oziExplorerCe, Mio Map and Garmin XT on an "unlocked" Mio 720 - cost $350, though you have to also buy regsiter copies and maps for programs such as OziExplorer/Garmin so that adds too total cost - but still less that HN. Not saying HN is not good buy - sound like many happy customers.

Cheers
Greg

Thanks guys, but I have tried 3 different USB drivers including the so called new and updated driver from magellan. I have all the latest maps for oziexplorer, and the magellan, so no problem there; just unable to get NMEA working after having upgraded the magellan with the updated firmware to run the new mappping software..

...what is the "new mapping software" - VantagePoint?
What version firmware are you using?
Can you uploadand download waypoints/track to PC OK?

Cheers
Greg

Explorist, Mapsend and Vantage point can be used to transfer files to the GPS, uploading and down loading way point and geocaching files. But both explorist and vantage point don't work (NMEA) with my Explorist. Vantage point is so basic doesn't allow 'port' changes or other system/setup changes (that I can find, anyway).

Sorry, the mapping software I was refering to was topo 2.27 maps. The firmware is ver.2.03 I had to load 2.03 as the new maps didn't funtion correctly with the old firmware, it kept freezing.

Everything used to work fine on my old laptop running XP, but it died and purchased a new vista machine not aware of all the problems this would cause.