Wednesday, 16 May 2007

Georeferencing - when we actually did it

We've been trying to put off georeferencing for as long as we can, but as Nanthinee said she was coming over on Tues, 15/5/07 to check on our progress, eventually we had to set our minds to the task.

By the way, when I talk about georeferencing, I mean 'find the coordinates of the location of this specific place on the Earth'. The two coordinates needed are the longitude (point on horizontal line) and latitude (point on vertical line). Longitude and latitude are measured in different ways, Google earth uses degrees/min/sec. I'm sorry for all the layman language but it's the easiest way I can explain.

So we started, and encounted problems.

Macritchie area, Thomson Ridge, on trail
So you thought the 'on trail' is insignificant right? That's what we thought too. And so we found the coordinates for Thomson Ridge. Which is entirely wrong! We should have georeferenced the trail beside Thomson Ridge!

Woodcutter's trail
Where the hell is it? Huh? We spent 1hr searching online for map of the trail. And we couldn't find it. Oh yea so we gleaned from various online sources that it starts near Dairy Farm Estate and ends near Upper Pierce Reservoir, but it didn't help in the georeferencing, at all.

Rifle Range Road, lamppost 95
Of course we couldn't find the exact location of a lamppost on any map. So we georeferenced the entire road by taking the midpoint. Which creates a large error as this particular road is very long.

So in the end, first attempt at georeferencing = failure :(

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