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surveying beyond the half a degree of the MGA zone

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dom1
 dom1
(@dom1)
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Topic starter
 

What would happen if i traversed beyond the half a degree beyond the MGA2020
Zone 54 boundary and just into Zone 55

What issues would occur if i continued to use MGA2020 Zone 54 for my
coordinate system for the new sections of the traverse? What recommendations and alternative options would you suggest so as to minimise these issues.

 
Posted : September 22, 2022 8:14 am
Rover83
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Posted by: @dom1

What would happen if i traversed beyond the half a degree beyond the MGA2020
Zone 54 boundary and just into Zone 55


GIF

In all seriousness, the answer is it depends. What's the goal of the project, are you actually running a terrestrial traverse in UTM (which as a LOT of distortion compared to other projections), is there a scale factor applied, are you reducing the traverse to grid, are you mixing it with GNSS?

 
Posted : September 22, 2022 11:15 am
MightyMoe
(@mightymoe)
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You will be fine, look at some zones for projection systems and you will find the limits are not straight but follow political lines. The farther you get from the central meridian of one zone the more you will be rotated from true north, but often you will lessen the distortion in the distances.

The older data sheets in my area would list NGS monument with coordinates from two states when those monuments were close to the state line. We would often survey across the state lines with the adjoining system from the neighbor state. Had to pick one or the other, when you cross the zone it makes sense to keep the coordinate system you started with. 

 
Posted : September 22, 2022 3:50 pm

OleManRiver
(@olemanriver)
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I traversed through 4 UTM zones in Africa. I just kept everything geodetic and once i knew my control was good i published coords in utm and mgrs for each zone according. Now its like crossing two state plane zones north bs south or east vs west. Pick one and call it good. Watch the distortion and choose one that limits it best you can. Or create your own system like LDP that allows you to match in each zone etc. 

 
Posted : September 22, 2022 3:53 pm
OleManRiver
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https://desktop.arcgis.com/en/arcmap/10.3/tools/coverage-toolbox/crossing-map-projection-zones.htm

 

I know this is not surveying but gives you an idea.  Above mentioned correctly that there are zones that are like crossing state plane zones often the counties that are split in a zone choose one over the other it’s political boundary like mentioned above. Google Virginia State Plane coordinate zones map a pdf is a great example on state plane. Overlay UTM over Djioubiti Africa and see the 4 zones I went through. Lol. Now Sometimes after crossing zones you have nightmares at night I found walking in reverse order cures this or was it the alarms going off that told me incoming or gas gas gas so I put on and off a mop suit a 100 times a day. Running into a bunker for some practice drill afte I had been awake for 24 hours. See I am fine you will survive. 

 
Posted : September 22, 2022 4:09 pm
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