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#1
David Medeiros

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Not sure if this qualifies as an info graphic, but it's not a map so I guess this is the best place for it.

 

At the SGC we always struggle with getting researchers to understand the issues involved with the differences between accuracy and precision; as well as false precision with too many decimal paces in a coordinate; and understanding why we don't measure in geographic coordinates.

 

This single page graphic is my attempt to provide a quick reference or cheat sheet for those issues in GIS. I found a few simialr sheets around online but nothing that put it all together.

 

Let me know what you think. This is not a primer on projections and coordinate systems, that graphic is still under development!

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GIS Reference and Instruction Specialist, Stanford Geospatial Center.

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#2
Melita Kennedy

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Somehow I would shoehorn in "1 degree" in the width of latitude/longitude box, but I'm not sure where! Thanks for the infographic! I like it a lot.

 

Melita



#3
hasecbinusr

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Great graphic!

#4
Hans van der Maarel

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I have a similar cheatsheet taped to my monitor with pretty much the same information, although I've also added the metric sizes of a minute and a second.


Hans van der Maarel - Cartotalk Editor
Red Geographics
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#5
DaveB

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I like it. Some great info in a compact form. It's easy to overwhelm people with too much info in these things. I think a good practice is to try to put the info on a small base while still keeping it easily legible; for example, what can you fit on a business card size or an index card or a small window on screen, or what you can you fit into a single short paragraph. I'm a fan of being concise. :)

I assume you know your audience and what kinds of questions and issues they run into, which is one of the keys to being able to be concise.


Dave Barnes
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#6
François Goulet

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Love it! 

 

First find that info in Alex Tait's Practical Cartographer's Reference. I always have it near my desk. Plenty of other use information.



#7
David Medeiros

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Love it! 

 

First find that info in Alex Tait's Practical Cartographer's Reference. I always have it near my desk. Plenty of other use information.

 

I have the PCR as well, love it! But it's too long to post around the lab. I like to break these topics out so they can be captured in a single sheet to post so students can easily glance at the info.

 

Thanks for all the positive feedback guys. Time to pass it on to the students.


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#8
tangnar

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Helpful indeed and I forwarded it around to GIS folks I work with. Thanks!



#9
David Medeiros

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New and improved version. Let me know if you actually want the PDF version of this, happy to pass it along.

 

Cheers,

David

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#10
Hans van der Maarel

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Thanks David. For what it's worth, here's my cheatsheet.

 

cheatsheet.jpg


Hans van der Maarel - Cartotalk Editor
Red Geographics
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#11
DaveB

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I can't read the red text in the gray globe in the lower left gray box. It's just a smudge. But maybe it's readable in person on a printed sheet/card/poster.


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#12
Strebe

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I think it's whatever renders your graphics, Dave. I see it all easily on my cellphone, even.

-- daan

#13
David Medeiros

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Here's the PDF for full resolutionality.

 

David

 

Edited: updated PDF per comments below.

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#14
westcoaster222

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Great post! The issue I continually run into similar to this is clients wondering if they can do 2m contour intervals from a 20m DEM. Sure you can I say but.... and then it begins.

 

Cheers,

Shep



#15
DaveB

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It's all greeking to me. :P

 

Even on the pdf at 100%, but it may be my old eyes, too. :/

 

As long as it works for you it's all good. :)


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