Determing the south west grid grid cell of topo srtm data

[winash12]

Hello,

            GIS newbie here. Please feel free to bump  my question into the right sub forum if it does not fit in here. If I choose Eurasia as my grid from here - http://dds.cr.usgs.gov/srtm/version2_1/Documentation/Continent_def.gif how to determine the grid cell that represents the south west direction i.e. south of the southern most point AND west of the western most point. Is this done by human inspection(trial and error) or some algorithm there than do it ?

[Lurker]

ehm, little bit confuse here,

 

let say you download one of that tiles that represent a small patch of the world in SRTM data, usually already georeferenced thus the orientation also fixed,

 

so you want to know the south west direction of the pixel (grid cell) of each images?

 

anyone have better understanding here? sorry Im not native, so maybe I'm wrong

[winash12]

In the grid that I downloaded i.e. there are 5876 .hgt files. How does one determine the south west corner of Eurasia and the latitude and longitude that corresponds to that grid cell ? I am not referring to the south west corner of individual grid cells but the south west corner of the entire 5876 files taken together as one grid. For a perfectly rectangular grid it is easy to determine the south western corner. How about the south western corner of Eurasia which is not perfectly rectangular ?

Edited October 4, 2014 by winash12

[Lurker]

I imagine that there is a map guide for that, an orientation map contain of all grid that place in the world map,

but if you cant find it in their official sites, I think you must manually mosaic all data and pick the corner you want, IMO

[winash12]

Of the two suggestions offered I like the second one better because it gives me something to code. I mosaic all the tiles of Eurasia and pick the south western corner of that mosaic. Thank you.

[Lurker]

glad you've made it