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UTM/UPS Grid-relative option in Walls

PostPosted: Feb 22, 2015 4:48 pm
by anti-jeff
Under the "Geographical Reference" tab when looking at project propeties in Walls, there's a check box for "UTM/UPS Grid-relative" in the coordinates section.

I read the help section on it and I think I have a vague understanding of what it does now, but I'm not sure about the "why" questions and when I'd use that option to what effect.

What are some considerations on whether or not I'd want to use UTM/UPS Grid-relative coordinates? If I do use that option and claim that my map is corrected to true north, am I technically lying?

Re: UTM/UPS Grid-relative option in Walls

PostPosted: Mar 9, 2015 6:41 pm
by flightfollowing
Not much help here, but here is some useful info:
http://www.cavediver.net/forum/showthre ... y-software

So one reason to use the UTM grid option is to be able to output in gis software which likely wants projected coordinates, rather than local or geographic.

concerning: "What are some considerations on whether or not I'd want to use UTM/UPS Grid-relative coordinates? If I do use that option and claim that my map is corrected to true north, am I technically lying?"

lots of software and maps want projected coordinates, so that they are planar, rather then geographic coordinates which are on an ellipsoid, math is much easier in a projected coordinate system.
Concerning lying about true north, my guess is that you would not be lying as long as you acknowledge it is a projected coordinate system.
I've also got a walls questions, but doubt it will be answered judging by the response to your question.