Friday, October 13, 2017

Unnecessary Concern of the Day: Snapping Beyond a 1:1 Scale

An ongoing head-scratcher for me has been why my points/lines/polygons look "off" in ArcMap when zoomed in beyond a 1:1 scale. Today, I found the answer to my question! A question, it turns out, that I didn't need to worry about in the first place.

The explanation I found for this issue is summed up as follows:
"Viewing linework at a viewing scale of less than 1:1 will show apparent offsets that are not real - i.e. they are not really what is going on. The polygons could be totally coincident, but below 1:1 look off. So some visually-seen disconcerting gaps/overlaps are actually not issues."

Here's ESRI Supports explanation:
"As per our phone interaction, a map scale past 1:1 is a known limitation of our software because at a scale of 1:1, the screen display is equal to the actual distance of objects on the earth's surface (i.e. an inch on your screen is equal to an inch on the ground). When you go past that scale, it may appear that features are overlapping (when in reality) what you are seeing is the actual software resolution tolerance pushed past it's maximum threshold. In essence, the entire screen is only one point (at a map scale of 1:0), which is why your work flow is producing inaccurate results."

Original Thread Here: https://community.esri.com/thread/180322

In other words, don't be fooled by the illusion beyond a 1:1 scale! Everything is Fine.....probably. Maybe set up a few topology rules to ease your worries for good?

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