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Old 30th July 2010, 22:01   #256
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Hi Sutripa, all my gps logs have altitude information. I am not sure of Harsh has preserved the altitude info in the gps track.
The altitude is GPS based.
To give you a rough estimate, hanle is 4100 or so and then it rises gradually to 5050 at kyun Tso.
Then it falls to around 4000 at nyoma section
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Old 30th July 2010, 22:18   #257
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I do not know if i have altitude info on my gps tracks! A little new with GPS devices :(.

I know that if i export my GPS track to Google earth, it does show me the road on a mountain there and not on a flat landscape. So essentially it should have the altitude information, but then again like i said, i really dont know for sure.
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Old 30th July 2010, 22:55   #258
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Harsh, mail me a gpx track, I will go through it and see if it has altitude and time stamps. In case if does not, then its better you use my tracks as much as possible.
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Old 30th July 2010, 23:08   #259
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Quote:
Originally Posted by tsk1979 View Post
Hi Sutripa, all my gps logs have altitude information. I am not sure of Harsh has preserved the altitude info in the gps track.
The altitude is GPS based.
To give you a rough estimate, hanle is 4100 or so and then it rises gradually to 5050 at kyun Tso.
Then it falls to around 4000 at nyoma section
As you know, GPS altitude is not very accurate. Add to it two other problems -
a) the Tibetan landmass causes WGS84 spheroid modelling to be most inaccurate there and
b) different GPSrs calculate elevation differently, and make no mention of it in their manuals.

I wanted to check these elevation data against DEM data. In a lot of cases, people/ software are stripping the original elevation data, and substituting DEM data. Often, the original data collector is not even aware of this! Which is why original raw data becomes important.

IIRC, Hanle was 4500m, and tallied very well with the spot heights given in the Soviet maps. Might be mistaken. Will check on Monday.

My interest started off with the "Khardung La - highest motorable road in the world" ....

BTW, what happenned to the Leh Srinagar section tracks? Missing both times!

Regards
Sutripta
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Old 31st July 2010, 00:04   #260
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thanks Suprita. Actually oziexplorer has an option "Apply SIRF altitude correction". I have not used that option, maybe I should.
I think my gps may be showing around 200m below actual altitude, as some data puts Thit Zarbo La etc., at 5300m and not 5110m as calculated by me. This means the kyun Tso lakes are at 5200m above sea level.
Can you tell me where can I look up DEM data for the lakes?
When I go to google earth and hover my mouse over these lakes it shows the same as my GPS
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Old 31st July 2010, 08:35   #261
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Quote:
Originally Posted by vardhan.harsh View Post
It's still a map which is being constantly updated. But the map for the given region is quite accurate. The data to plot this map has been taken as a cumulative of other maps + GPS data & distances data from users such as Tanveer, others & myself.
Attachment 396409


GPX file is still a work in progress. will upload it too once i'm done.
Harsh,

Awesome effort cute and functional map. Tnx for sharing.

------
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Old 31st July 2010, 21:59   #262
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Quote:
Originally Posted by tsk1979 View Post
...
Can you tell me where can I look up DEM data for the lakes?
When I go to google earth and hover my mouse over these lakes it shows the same as my GPS
4985m I think. Also the value from SRTM.

I use SRTM data from CGIAR-CSI SRTM 90m DEM Digital Elevation Database

GE matches so well with SRTM data that I think GE used SRTM for its modelling. Google Maps terrains do not always match with GE. Your guess is as good as mine as to why.

I have not been able to get ASTER data for free. From time to time some workarounds are given on the net to download this. Not been able to get any of them to work.

Normally if you BUY one of the standard GIS packages, access to quite a few paid sites is bundled with the package. Ozi3D has some information on various free sources.

For spot heights and contours, you can try the Soviet maps. On your trip last year, the spot height given for Hanle in the Soviet map, and your GPS data had uncanny similarity.

It is difficult to get authoritative information on what the elevation data is ellipsoid, MSL, ........

Regards
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Old 1st August 2010, 03:31   #263
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Read all 18 pages at one go! Thanks tsk for taking to such a nice journey.

Regards
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Old 1st August 2010, 14:44   #264
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@ Harsh : sincere appreciation for the efforts taken, excellent work.

the map strictly shows 4x4 for certain areas; but I will not lose hope and try with my 4x2 Xylo - Wat say Ramky / TSK sir ?!

@ TSK :
if you were using Slime, pl do put light on that subject.
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Old 1st August 2010, 15:52   #265
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Quote:
Originally Posted by pcpranav View Post
@ Harsh : sincere appreciation for the efforts taken, excellent work.

the map strictly shows 4x4 for certain areas; but I will not lose hope and try with my 4x2 Xylo - Wat say Ramky / TSK sir ?!

@ TSK : if you were using Slime, pl do put light on that subject.
The road conditions there are dynamic and presents the current condition at the point of time of the drive. For e.g. the section from Chang-la to Pangong, Kardung to Nubra were very good most of the way this year, can't say about next season. Sections around Wari-la, ascent to M-top, Spangmik, Loma, Puga to More plains sections are not good most of the time requiring ideally 4x4 drives.

For safetys sake, I would take this map for what it is worth and WILL NOT attempt sections marked in Red on my 4X2 unless I have a couple of cars with me, salvage equipment and have on the ground reports the roads have improved drastically.

---------

Last edited by ramkya1 : 1st August 2010 at 15:55.
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Old 2nd August 2010, 11:51   #266
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Quote:
Originally Posted by Sutripta View Post
4985m I think. Also the value from SRTM.

I use SRTM data from CGIAR-CSI SRTM 90m DEM Digital Elevation Database

GE matches so well with SRTM data that I think GE used SRTM for its modelling. Google Maps terrains do not always match with GE. Your guess is as good as mine as to why.

I have not been able to get ASTER data for free. From time to time some workarounds are given on the net to download this. Not been able to get any of them to work.

Normally if you BUY one of the standard GIS packages, access to quite a few paid sites is bundled with the package. Ozi3D has some information on various free sources.

For spot heights and contours, you can try the Soviet maps. On your trip last year, the spot height given for Hanle in the Soviet map, and your GPS data had uncanny similarity.

It is difficult to get authoritative information on what the elevation data is ellipsoid, MSL, ........

Regards
Sutripta
Well my GPS gives 5020 for the track which was a few meters higher than the lakes. So I guess my GPS data is closer to the real values.
I am still wondering whether to apply SIRF data correction ,since mio c320 does have a SIRF chipset
Quote:
Originally Posted by naren_gs1 View Post
Read all 18 pages at one go! Thanks tsk for taking to such a nice journey.

Regards
Thanks Naren
Quote:
Originally Posted by pcpranav View Post
@ Harsh : sincere appreciation for the efforts taken, excellent work.

the map strictly shows 4x4 for certain areas; but I will not lose hope and try with my 4x2 Xylo - Wat say Ramky / TSK sir ?!

@ TSK :
if you were using Slime, pl do put light on that subject.
The areas which are marked yellow can be done by taxis. There is some difficulty on some sections where you may have to get down and scout for the path with least sand, but its mostly doable.
Regarding the red section, in future the Agam-shyok-pangong section may become 2wd motorable, but as of now, its strictly 4x4 only. Its loose rocks and even on 4L I was getting occasional wheelspin. Also rock crawling on HT tires can cause tire damage, but Harsh managed fine due to control given by low ratio.
Regarding other sections(kyun Tso, Chumur), remember if you get stuck, the next vehicle will come probably after a couple of days. There are some tracks so sandy that even with 4x4 I was struggling. It was like driving on the sandy tracks of jaisalmer.
At some sections the track looked like more plains flat sand, but actually it was "very soft soil" and we started sinking, timely throttle and literally gunning for the alternate track saved us.
Remember if you get stuck, even 5-6 people will not be able to push out a 2 ton vehicle.
If you look at the qualis video, you will see it needs another vehicle to pull out a bogged down vehicle.
So if you have a companion 4x4 you can take the risk of attempting those sections marked in red.
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Old 2nd August 2010, 16:11   #267
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Quote:
Originally Posted by tsk1979
We cross over, and realize that today the sun will most probably not grace Nubra valley, its cold and icy


TO BE cONT
tsk can you recall the date and time when you witnessed this ice? Whar could be the temperature. I just love it. Nature's pating
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Old 2nd August 2010, 16:51   #268
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It was around 8th June, 2010 around 11:30am, just after crossing Khardung La.,
Till around mid june you easily fine such snow on the Khardung La top
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Old 2nd August 2010, 17:33   #269
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Quote:
Originally Posted by ramkya1 View Post
Harsh,

Awesome effort cute and functional map. Tnx for sharing.

------
Thanks ramky

Quote:
Originally Posted by pcpranav View Post
@ Harsh : sincere appreciation for the efforts taken, excellent work.

the map strictly shows 4x4 for certain areas; but I will not lose hope and try with my 4x2 Xylo - Wat say Ramky / TSK sir ?![b]
Quote:
Originally Posted by tsk1979 View Post
Regarding the red section, in future the Agam-shyok-pangong section may become 2wd motorable, but as of now, its strictly 4x4 only. Its loose rocks and even on 4L I was getting occasional wheelspin. Also rock crawling on HT tires can cause tire damage, but Harsh managed fine due to control given by low ratio.
Regarding other sections(kyun Tso, Chumur), remember if you get stuck, the next vehicle will come probably after a couple of days. There are some tracks so sandy that even with 4x4 I was struggling. It was like driving on the sandy tracks of jaisalmer.
At some sections the track looked like more plains flat sand, but actually it was "very soft soil" and we started sinking, timely throttle and literally gunning for the alternate track saved us.
Remember if you get stuck, even 5-6 people will not be able to push out a 2 ton vehicle.
If you look at the qualis video, you will see it needs another vehicle to pull out a bogged down vehicle.
So if you have a companion 4x4 you can take the risk of attempting those sections marked in red.
pcpranav, Yes as ramky mentioned there are certain tracks which are seasonal and one could take a chance with a 4x2 Xylo on those tracks. These tracks are marked in yellow and even some of the black marked roads could become red seasonally.

However the currently red marked roads as tsk mentions is strictly for 4x4 only, and are season indepenent. They even become undoable in 4x4 vehicles seasonally!. And unless you are ok to be stuck without help for couple of days (and on some tracks a forthnight!), do not try this in a 4x2 for the time being.
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Old 2nd August 2010, 18:46   #270
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I really dont know why people look for Europe and Cananda for chill and ice?

"People look at the above place and think where do you want to go Europe or Khardung La?"

A person like me sitting in Chennai at 37*C will know the worth of Khardung La. Thanks a Tonn for that photo TSK.

Jai Ho
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