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NZ Orthophotos

Related to data sources. The special issues of choosing the right ones, resolution, tiles, positioning in OCAD

MT: Michael Posted: 30 May 2014, 11:08 AM

When you download from those magnificent LDS photos for a big area you get a lot of “tiles”. (1×1.5km in the one I'm using.) You can easily open them as a group with shift-select, but is there a way to switch them on/off, dim etc as a group in OCAD? From time to time I want to see my OTHER backgrounds.

MT: Dwayne Posted: 30 May 2014, 11:38 AM

I joined 4 jpg tiles together which helped me get around the 5 background image limitation of OCAD 11 Starter Edition. Use GIMP and open all jpgs as different layers, slide them around to match up and then export as new jpg. Then rename the JGW file of the top left corner tile to match the new file name. Then there is just one background image to toggle.

MT: Michael Posted: 30 May 2014, 4:28 PM

Thanks. You're relying on matching them up by eye?

MT: Dwayne Posted: 31 May 2014, 10:39 AM

The tiles I download from Auckland Council GIS website don't overlap and GIMP has an align layers function to snap them together. I used 800% magnification at first (before I discovered the layer alignment function) to move selected layer pixel by pixel which worked as well.

mapping/orthophotos.txt · Last modified: 12:50pm Tue 25 October 2022 by