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Old 2nd August 2010, 20:11   #271
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Originally Posted by tsk1979 View Post
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
Hi,
This is hardly the place to discuss GPS technology (lots of other forums for that). Having said that, lets continue. I don't think you have to apply any correction. (Sirf used to report the ellipsiodal altitude. Even in NMEA sentences, which expected MSL referenced altitudes. This has long since been corrected by a firmware upgrade. The SirfDemo pdf makes for interesting reading.) I think you can confirm it by asking in the mio and OziCE forums. In any case GPS altitudes leave something to be desired. Which is why we have GPSrs with barometric altimeters.

The 5000m contour line encircles both the Kyo Tso lakes. And it is apparent that a rise in water level of just a few m will join the lakes into one.

Hydrologists/ geologists can comment with far greater authority, but I think the lakes were once joined, with both an inlet (stream) and outlet. Then for some reason the water level dropped, separating the two. The one which gets the water turned salty. The fresh water one will vanish over time.

I believe there was a lot of unusual rain in Ladakh this year. Any repercussions on the lake levels?

Regards
Sutripta
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Old 2nd August 2010, 21:20   #272
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Originally Posted by vinod_namakkal View Post
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
Vinod, you do not need to go as far as khardung LA. If you cannot get time to do ladakh, then simply do manali Narkanda etc., in HP in February. You will get to experience lots of snowfall live.

Quote:
Originally Posted by Sutripta View Post
Hi,
This is hardly the place to discuss GPS technology (lots of other forums for that). Having said that, lets continue. I don't think you have to apply any correction. (Sirf used to report the ellipsiodal altitude. Even in NMEA sentences, which expected MSL referenced altitudes. This has long since been corrected by a firmware upgrade. The SirfDemo pdf makes for interesting reading.) I think you can confirm it by asking in the mio and OziCE forums. In any case GPS altitudes leave something to be desired. Which is why we have GPSrs with barometric altimeters.

The 5000m contour line encircles both the Kyo Tso lakes. And it is apparent that a rise in water level of just a few m will join the lakes into one.

Hydrologists/ geologists can comment with far greater authority, but I think the lakes were once joined, with both an inlet (stream) and outlet. Then for some reason the water level dropped, separating the two. The one which gets the water turned salty. The fresh water one will vanish over time.

I believe there was a lot of unusual rain in Ladakh this year. Any repercussions on the lake levels?

Regards
Sutripta
Yes, even I think they were one. But the thought of one dissapearing makes me sad.
Regarding levels of lakes, this region of changthang did not get much precipiration, only regular rain. It was mostly concentrated to khardung/Chang La axis, with Nubra getting a fair amount of rain.
Moreover, this was the first time I did these lakes, so cannot really say if water levels have gone up.
I am pretty sure there are no streams feeding the lakes, just the run off from the surrounding hills(the range separating the Tso moriri valleys from Kyun Tso)
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Old 2nd August 2010, 22:05   #273
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^^^^^^^
A bit of googling gave this
http://www.ias.ac.in/currsci/dec102005/1941.pdf

4973m. And a lot more.

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Sutripta
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Old 2nd August 2010, 23:05   #274
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Originally Posted by vardhan.harsh View Post
Thanks ramky





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.
@ Tanveer, Ramky, Harsh: thanks a ton for your valuable inputs. I have decided for next year - lets see whats in store that time and make the best with whatever my 2WD-Xylo can stride!
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Old 5th August 2010, 22:20   #275
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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,
First of all, hats off for a superb effort.

I downloaded your kmz file (from the other site), and overlaid the tracks on both other peoples tracks, and OSM. There are significant differences at places. I would suggest that where a gps trackplot exists, that be used in preference to tracing over GE. And those tracks which are traced be clearly marked as such.

Also the file I downloaded seems to be incomplete compared to your jpg.

Regards
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Old 5th August 2010, 22:45   #276
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Quote:
Originally Posted by Sutripta View Post
@Harsh,
First of all, hats off for a superb effort.

I downloaded your kmz file (from the other site), and overlaid the tracks on both other peoples tracks, and OSM. There are significant differences at places. I would suggest that where a gps trackplot exists, that be used in preference to tracing over GE. And those tracks which are traced be clearly marked as such.

Also the file I downloaded seems to be incomplete compared to your jpg.

Regards
Sutripta
thanks sutripta,

Yes, the kmz file is a very rough approximation of the actual track one would use. We had marked the track on google earth, before our trip, following the traces of a road that one would see. Of course it needs to be further refined by using the actual GPS traces of the route, either ours or someone else's. Of course the track for which there is no GPS data would be marked as such.

I might need some help and you seem quite knowledgeable on GPS. I would need to edit some tracks, prune it and make it a little better. Or in some cases merge some tracks. Any ideas on how this could be done?
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Old 5th August 2010, 23:08   #277
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Originally Posted by vardhan.harsh View Post
thanks sutripta,
...
I might need some help and you seem quite knowledgeable on GPS. I would need to edit some tracks, prune it and make it a little better. Or in some cases merge some tracks. Any ideas on how this could be done?
Cutting, joining, decimating no problem. How are you doing it now? And what tools (programs) do you have access to?

If by merging, you mean finding the best 'fit' from GPS traces of the same road made at different times, well then I know of no method other than manually digitising them.

Let me know if there is any way I can help.

Regards
Sutripta
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Old 6th August 2010, 09:55   #278
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Suprita, for Hanle-Kyun Tso Nyoma and Loma-chushul-pangong-Tangste-shyok-Agam you can get my tracks from openstreetmap.
They can replace the kmz,
Harsh, you can use your sportstracker file for the chumur section.
Between both of us, we have gpx for the entire map, so just recreate the map using the kmz generated from gpx. There will be duplication, but in the end you want to create a jpg map, so no issues!
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Old 6th August 2010, 16:24   #279
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Quote:
Originally Posted by Sutripta View Post
Cutting, joining, decimating no problem. How are you doing it now? And what tools (programs) do you have access to?

If by merging, you mean finding the best 'fit' from GPS traces of the same road made at different times, well then I know of no method other than manually digitising them.

Let me know if there is any way I can help.

Regards
Sutripta
Hey Sutripta,
Thanks for your help offer. Now i guess i would not been needing it since Tanveer has taken it upon himself to make the GPX track for the entire region!
As of now i'm a little dense about GPS editing and have no programs to edit it. I just have Google earth with me, where i can view them GPS tracks.

Quote:
Originally Posted by tsk1979 View Post
Harsh, you can use your sportstracker file for the chumur section.
Between both of us, we have gpx for the entire map, so just recreate the map using the kmz generated from gpx. There will be duplication, but in the end you want to create a jpg map, so no issues!
As you have suggested ;-). I'll send over the GPX to you today, and you could do the rest. Although we do not have the gpx for Chushul - Mahe route, but i've traced it out on google earth and that might be used as well.
Will send it over too.
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Old 6th August 2010, 20:24   #280
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Originally Posted by tsk1979 View Post
Suprita, for Hanle-Kyun Tso Nyoma and Loma-chushul-pangong-Tangste-shyok-Agam you can get my tracks from openstreetmap.
Thanks. But downloaded within a couple of days of yours uploading it! Yours was one of the tracks I checked Harsh's jpg against.

Quote:
Originally Posted by vardhan.harsh View Post
Hey Sutripta,
Thanks for your help offer. Now i guess i would not been needing it since Tanveer has taken it upon himself to make the GPX track for the entire region!
As of now i'm a little dense about GPS editing and have no programs to edit it. I just have Google earth with me, where i can view them GPS tracks.

As you have suggested ;-). I'll send over the GPX to you today, and you could do the rest. Although we do not have the gpx for Chushul - Mahe route, but i've traced it out on google earth and that might be used as well.
Will send it over too.
Two free programs I would suggest are GPSBabel (a must have) and GPXEditor. The latest version of GPSBabel is GUI based, so much easier to use. Do note though that ver 1.4.1 has a bug in converting TO kml. GPXEditor too has a memory leak problem, so hangs if trying to edit large tracks. Fine for viewing, and for editing small tracks.

Would suggest you use GPX as the mother file format. It is the defacto standard now.

Regards
Sutripta

PS. I have a feeling we'll show SoI how maps are done, and maybe they will get out of their 'everything is a secret/ national security will be compromised' mindset.
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Old 7th August 2010, 03:13   #281
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Quote:
Originally Posted by Sutripta View Post
Two free programs I would suggest are GPSBabel (a must have) and GPXEditor. The latest version of GPSBabel is GUI based, so much easier to use. Do note though that ver 1.4.1 has a bug in converting TO kml. GPXEditor too has a memory leak problem, so hangs if trying to edit large tracks. Fine for viewing, and for editing small tracks.

Would suggest you use GPX as the mother file format. It is the defacto standard now.

Regards
Sutripta

PS. I have a feeling we'll show SoI how maps are done, and maybe they will get out of their 'everything is a secret/ national security will be compromised' mindset.
Thanks Sutripta for your suggestions. Would surely look into GPSBabel. Sounds like a decent software to begin working with.
Have a nice weekend.
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Old 8th August 2010, 22:25   #282
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My first version!!

I have created the scale accurate map. I have mapped sections with GPX available. Rest, I have not added anything.
Ladakh and Changthang : The Wilderness Chronicles-full_map_nubra_changthang.jpg
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Old 9th August 2010, 13:26   #283
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Hi Tsk,

I don't see Nubra valley in this map, is't it somewhere in between PangongTso and Hanley.
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Old 9th August 2010, 13:28   #284
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Originally Posted by somu_john View Post
Hi Tsk,

I don't see Nubra valley in this map, is't it somewhere in between PangongTso and Hanley.
Hunder Diskit and Panamik are in the Nubra valley!
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Old 9th August 2010, 16:59   #285
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hey, the map looks nice, how did you export the gpx into jpgs automatically? or is it merging of different screenshots?
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