landclass data, projections etc.

[Guest rafaelds]

Hi everybody.I am having lots of trouble importing land class data into BGL. Basically, most data around the internet seems to be in goode or lambert azimuthal equal area projections. Lots of distortion is appearing in the output, it does not matter how I estimate lat/lon coordinates for the data.How are you guys overcoming these problems? Are there utilities for 'resampling' the data into another projection?Thanks.

[Justin Toposim 16]

HI Rafael,I, personally, use Manifold 5, and powerful yet inexpensive GIS to prepare virtually all my projects for BGL output. It can import virtually any GIS format and export to virtually any GIS format, and do a lot of data manipulation in between.http://www.manifold.netYou may find some freeware utilities out there somewhere. Just ask google (search for "free GIS software"). Don't know any specific ones off the top of my head, though, since I've been using Manifold for so long and it does everything I need it to do.There's one that many people use, but it's name escapes me at the moment. Oh, it's called Microdem. I'm not sure if it does reprojection, but probably. You need to have your data in lat/longitude coords, WGS84 datum.Hope this helpsJustinhttp://www.fsgenesis.com

[Guest rafaelds]

Thanks for the tip, Justin.After a lot of search I found only two freeware GIS software. The most famous is called GRASS, but it's basically an Unix app. To run in Windows, one would have to download dozens of libraries and x-server things and still have limited functionality. Oh, and NTFS is mandatory.The second option, for my surprise, came right here from Brazil. It's a freeware GIS called SPRING. They say it's a 'state-of-the-art' GIS, and from my testing I can say it's got at least a state-of-the-art complexity level. Even after sucessfully completing the tutorials, I was unable to make anything. Besides, there wasn't any projection like the ones I needed in the options...Then I decided to give a try in a demo of a commercial product, called 'The Geographic Transformer'. This demo would allow me to select ONE image in my hard disk and use it fully within that image only. Well, I gave it a try anyway... and I must say this program rocks. It has dozens of projections, ellipsoids and datums available to choose from, and everthing is as simple as: open an image, select projection, define at least three points, select output projection, boundaries and resolution and click OK. It works like a charm! And it's fast - a full South America conversion took some seconds! When I was trying to import data in SPRING I gave up after waiting over an hour of processing... And this program does more: you can specify 'no projection', and define as many points with coordinates as you want. This makes it possible to 'undistort' aerial pics which were taken not exactly vertically, or where the relief is not flat.Stepping back into reality, this program costs 800 dollars.But it's worth a try.Rafa

[Guest]

Rafa,As soon as I read your post, I

[Guest rafaelds]

hang on a little more, I will tell everybody what I did.school break just started today so I will have some time soonRafa

[Guest]

Hi Guys,Have a look here for some free image georeferencing software: http://software.geocomm.com/raster/www.gisdatadepot.com is a good site for free GIS goodies.Cheers,Derek