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  • Please see the most recent updates in the "Where did the .com name go?" thread. Posts number 16 and 17.

    Post 16 Update

    Post 17 Warning

Should have done this long ago.

I've been using Global Mapper to download, re-project and save images as geotiff for photo scenery projects. It's expensive, but sure makes it easy. A lot of times I'll just enter the airport coordinates and tell Global Mapper to download an area X miles from that center. Since I generally work with large areas, I have it export at 2m/pixel. If it's a large file, I can set Global Mapper to break it up into rows and columns of equal size.

Global Mapper also works with N, S, E, W coordinates which came in handy recently. On my current scenery, I started with 60 miles x 60 miles centered on KPRC (Prescott). After running resample, I noticed it was really close to Sedona, so I used the N, S and E coordinates of the existing area, then gave it a new E coordinate to add. The new scenery is 60 miles x 83 miles and extends well past Sedona. Then I noticed I was awfully close to KFLG (Flagstaff), but resisted the urge to expand the scenery again.

Global Mapper exports geotiffs and can also export a "TFW" file with the information. This makes is easy to edit a geotiff (color correction, night textures, water and blend maps), and make it back into a geotiff when finished. Just import the edited tif with a TFW file of the same name and Global Mapper makes the correct projection. Then export a new geotiff.

Instead of importing from Google, Global Mapper can download the image from pay sites or USGS (free).
 
kjb said:
Global Mapper exports geotiffs and can also export a "TFW" file with the information.
Click to expand...

Nice to see you back active, Kevin!

I don't know the dates for the imagery tthat GM may grab, but if it's NAIP then it will be fairly current. NAIP is going to be compressed data, which is generally OK. If you're a stickler for detail, there are some sites that have AZ imagery in their pure GeoTiff format. Downloading all of Kalifornia was a long process and still fills the majority of a 2TB HD.

Also, if you're doing a large area and there are many files and there are many TFWs, I wrote a small little program to read all those TFWs and make INF files for use in Resample. It's been a while since I used it and I would have to go back and re-familiarize myself with the spaghetti code. But if you have a lot of files and don't want to cut and paste, cut and paste, cut and paste, it can be a time saver.

IIRC, Kalifornia is 12,000 files and there's no way I would cut and paste that many files! :isadizzy:
 
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