Explain Georeferencing To Me as If I Were a Five-Year-Old

17954
49
11-30-2016 08:11 AM
AdrianWelsh
MVP Notable Contributor
77 49 18K

I really liked how Denzel Washington used the phrase “explain this to me as if I were a xxx-year-old” in the movie Philadelphia (1993).

Reference: Philadelphia. Philadelphia, PA: Jonathan Demme, 1993. film.

 

So, I will take it one step further and attempt to explain the concept of georeferencing to an actual five-year-old.

 

Five-year-old:

Five-year-old engineer says, “I have this PDF of a site plan. I want to put this on a map and have it line up properly.”

 

Here is my map.

 

We need to zoom in a little bit closer.

 

Open Street Map 1:100,000<-- click to make larger

A little bit more.

 

Open Street Map 1:5,000<-- click to make larger

Almost there. Zoom in some more so that our site plan will fit better.

 

Open Street Map 1:1,050<-- click to make larger

Much better. Now, we need to shrink the site plan to a more usable size. Currently, it’s larger than our map.

 

Let’s make it a little bit smaller.

 

Perfect. Now we need to place the site plan on our zoomed in map and adjust it to fit by rotating it and resizing it.

 

Great! Now, after some quality control of adjustments and transformations, we can rectify this image and call it georeferenced!

 

OSM 1:1,050 with Image<-- click to make larger

We can make the georeferenced image transparent to where we can see the basemap behind it.

 

OSM 1:1,050 with Image, Transparency 50%<-- click to make larger

Finally, we can add existing linework and other GIS files to give the image a more solid reference.

 

OSM 1:1,050 with Image, Transparency 50% and Linework<-- click to make larger

Voila!  

Please leave comments and let me know if this is helpful and/or what I should change with this blog post. Thanks for reading!

49 Comments
DanPatterson_Retired
MVP Esteemed Contributor

Love it!   Good help is hard to find... you have excellent support.

AdrianWelsh
MVP Notable Contributor

Haha, thanks Dan! It's true, good help is hard to find.  

JoeBorgione
MVP Esteemed Contributor

That's great! 

KimberleeShulsen
New Contributor

I really liked this explanation!!!

PanGIS
by
Regular Contributor

Still laughing.

That's great!

MelodyRose
New Contributor III

This is an excellent presentation! It is very creative. I am still somewhat new to GIS and this is a good lesson for someone who is new to GIS. Thank you for sharing!

AdrianWelsh
MVP Notable Contributor

Melody, I'm glad you liked it! I suppose I should make more GIS-for-beginners-type blog posts! Thanks for the comments.  

MelodyRose
New Contributor III

Adrian, you're welcome.

Lake_Worth_BeachAdmin
Regular Contributor

Very nice! 

AnthonyPankala
New Contributor II

Huh, so that's the technical term for what issues I keep fighting so hard to figure out .  This will make my Google searching A LOT more useful when trying to find the solution .

Nicholas-Furness
Esri Regular Contributor

That's superb! Thanks for posting this and congrats to the assistant. Great job!

LasseElden
New Contributor

Gr8!

Let's say this 5-yearold now was 42 and just had just got ArcPro.

How would he (or I) geoforce a TIFF file into ArcMap. Let's say... 100% step by step?

HeidiRagsdale
New Contributor II

I think this is a great explanation!  Kids really do get it! 🙂

AdrianWelsh
MVP Notable Contributor

Hi Lasse,

Take a look at this link for instructions on how to georeference in ArcGIS Pro.

Georeferencing tools—ArcGIS Pro | ArcGIS Desktop 

Let me know if you need more guidance.

Thanks,

Adrian

PROBERT68
Regular Contributor III

Awesome !!!!!

PernillaLindblom
New Contributor

Great! I'd never heard about georeferenced before and know little about GIS but I understood this, so great work, wonderfully explained

AdrianWelsh
MVP Notable Contributor

Pernilla,

I am glad it was helpful!

EvanD
by
New Contributor II

I think the devil is in the, "Now, after some quality control of adjustments and transformations, we can rectify this image and call it georeferenced!" part.

MauriceCasalta
New Contributor

I love it!

AdrianWelsh
MVP Notable Contributor

Well, yeah. I think that each of those terms could possibly be broken down to be 'explained' to a five-year-old as well. It just might take quite a bit longer...

AyeletGreenberg
Occasional Contributor

Wonderful 🙂

AnitaPalmer
Occasional Contributor

This was brilliant. Please do a series...I would be a big fan! Thanks!

ElamarHienrich
New Contributor III

This is great! 

AdrianWelsh
MVP Notable Contributor

What would be another topic to explain to five year olds?

yangzhang
New Contributor

Great! Look forward next topic

RuiSantos
Esri Contributor

This is great! I will try to use this 5 years old exemple to other topics.

JohanesFerdinand
New Contributor

Congratulation for this great work, its interestesting and easily understood.Keep it up!

AnjoletteSpradling
New Contributor III

Geocoding. I once tried to explain it to adult IT Analysts.

GünterDörffel
Occasional Contributor III

Nice! It proves that

  • work plus fun : possible
  • gis plus family (I assume): possible
  • and finally: Georeferencing: possible 🙂
MuhaimenAyyub
New Contributor

Nice one.

AdrianWelsh
MVP Notable Contributor

Hmmm, geocoding would be a great one. I don't use geocoding enough to feel like I could explain it to a five-year-old. The simple gist of it could be easily explained, but explaining how to create an address locator and what all the options are for what can go wrong/right, etc. ... that could get complicated quickly! I'll have to think about this one.

RebeccaStrauch__GISP
MVP Esteemed Contributor

Suggestion....think locally.  How would you explain your address to your daughter.  Then how would you explain the address of you neighbor...or next apt, if that is the case.  The say, start with country, state, city, street address, house number....and reverse.

AdrianWelsh
MVP Notable Contributor

Ugh, now I have to think more...   Thanks for the suggestions. These are quite good. I'll give it some thought see if I can come up with anything clever or creative.

AdrianWelsh
MVP Notable Contributor
AndréPiasta
Esri Contributor

Awesome!
I'm an instructor and you did a far better job than I've ever done explaining georeferencing.

At risk of putting myself out of a job, I'm going to point my future classes at your post(s).

AQeelhilali
New Contributor

Simple and helpfull, thanks

JanHalatsch1
New Contributor

Nice one! Thanks.

AitorCalero_García
Esri Contributor

Absolutely great!

AtharCush
New Contributor

I have been agonizing over this problem for almost one year.

MarilyPaipeti
New Contributor II

Just lovely!

ArleneOwen
New Contributor

Excellent!

AlexWood2
New Contributor II

This is absolutely adorable. I wish everything in life could be explained by and to a 5-year old XD

AnninaHirschi_Wyss1
Occasional Contributor III

Hi Adrian Welsh

Love it!

Do you plan to "Explain Projections To Me as If I Were a Five-Year-Old" ? (even if she's six by now...) That would be of great great use for our GIS introduction courses 😉

cc Connie Schmidt‌, Nicole Ueberschär

AdrianWelsh
MVP Notable Contributor

Hi Annina,

That is the next one I want to do. Time and other things have completely gotten in the way of this, unfortunately. But I'll surely post something here when I do (if I do) make that blog post.

CoryBlackEagle1
New Contributor II

Great post and explanation!!!  Only question is this:  what exactly do you mean by "some quality control of adjustments and transformations"?  Kind of like that great cartoon.

Sydney Harris and-then-a-miracle-occurs cartoon

AdrianWelsh
MVP Notable Contributor

Cory,

This is more-or-less another way of saying that there is more involved in this process than just simple insert-map-and-be-done. Here is a link showing how to align the raster with control points (the adjustments):

http://desktop.arcgis.com/en/arcmap/10.3/manage-data/raster-and-images/fundamentals-for-georeferenci...

And here is a link showing how to use transformations (from the same article):

http://desktop.arcgis.com/en/arcmap/10.3/manage-data/raster-and-images/fundamentals-for-georeferenci...

JpersonalLundquist
New Contributor III

love this. Thank you, at 62 humor is refreshing. I am returning to the fetal position and probably the mind of a 5 year old. I have to say georeferencing is one of my favorite things to do; it can be a challenging (to get it right for the job at hand).

Thanks

RiccardoKlinger2
Occasional Contributor

One year ago I was trying to explain a polynomial transformation as well. Maybe not for the five year olds 😉

AdrianWelsh
MVP Notable Contributor

That was nice, I liked it!

About the Author
Experienced Consultant with a demonstrated history of working in the computer software industry. Skilled in ArcGIS, Maps, Databases, and Geography. Strong consulting professional with a Degree on Geography and Regional Planning from Universidade Nova de Lisboa (New University of Lisbon).