Comments on: Google Map Scale per zoom level… http://laudontech.com/GISBlog/?p=28 Stay tuned for random GIS banter are of Laudontech... Thu, 02 Sep 2010 09:49:40 -0700 http://wordpress.org/?v=2.8.6 hourly 1 By: Martin http://laudontech.com/GISBlog/?p=28&cpage=1#comment-219 Martin Thu, 08 Jul 2010 10:37:00 +0000 http://laudontech.com/GISBlog/?p=28#comment-219 @zroq: The difference in scale is not a bug. Google Maps uses a map projection similar to the Mercator projection. This means that the closer you get to the poles, the larger everything becomes. There's no helping it if you have to project a sphere onto a plane. To test this, simply zoom out a bit and drag north or south, and you will see the scale change dynamically. @zroq: The difference in scale is not a bug. Google Maps uses a map projection similar to the Mercator projection. This means that the closer you get to the poles, the larger everything becomes. There’s no helping it if you have to project a sphere onto a plane. To test this, simply zoom out a bit and drag north or south, and you will see the scale change dynamically.

]]> By: Brian Corbett http://laudontech.com/GISBlog/?p=28&cpage=1#comment-206 Brian Corbett Mon, 10 May 2010 13:23:27 +0000 http://laudontech.com/GISBlog/?p=28#comment-206 mapping to MapInfo's Zoom window width using stare and compare in the Louisville, Ky area: multiply width by 2 on up 16 = 1.5 mi 17 = .75 divide width by 2 on down mapping to MapInfo’s Zoom window width using stare and compare in the Louisville, Ky area:

multiply width by 2 on up
16 = 1.5 mi
17 = .75
divide width by 2 on down

]]> By: Carlos Krefft http://laudontech.com/GISBlog/?p=28&cpage=1#comment-191 Carlos Krefft Fri, 04 Dec 2009 19:43:46 +0000 http://laudontech.com/GISBlog/?p=28#comment-191 This is what i use: 1128.497176 2256.994353 4513.988705 9027.977411 18055.954822 36111.909643 72223.819286 144447.638572 288895.277144 577790.554289 1155581.108577 2311162.217155 4622324.434309 9244648.868618 18489297.737236 36978595.474472 73957190.948944 147914381.897889 295828763.795777 591657527.591555 This is what i use:
1128.497176
2256.994353
4513.988705
9027.977411
18055.954822
36111.909643
72223.819286
144447.638572
288895.277144
577790.554289
1155581.108577
2311162.217155
4622324.434309
9244648.868618
18489297.737236
36978595.474472
73957190.948944
147914381.897889
295828763.795777
591657527.591555

]]> By: zroq http://laudontech.com/GISBlog/?p=28&cpage=1#comment-188 zroq Fri, 11 Sep 2009 21:33:30 +0000 http://laudontech.com/GISBlog/?p=28#comment-188 you would never be able to compare two different cities in size , for example paris and nyc. because the scale is different for each area . it means that 2 miles looks different in paris than in nyc , this is a bug , hopefully google will discover this problem and fix it. try to put the scale at 2 miles in nyc and then for paris , you will see that you won't be able to get the same distance for 2 miles in each city , in paris for example 2 miles will show up as 2miles = 1 inch , but when you scroll to nyc , yes that is a long scroll , the scale will suddenly change to 2 miles = 1,5 inch , and there is no way to escape this bug . too bad , now it is hard to put 2 cities next to eachother from different maps to see the size of a town compare to another city. you would never be able to compare two different cities in size , for example paris and nyc. because the scale is different for each area . it means that 2 miles looks different in paris than in nyc , this is a bug , hopefully google will discover this problem and fix it. try to put the scale at 2 miles in nyc and then for paris , you will see that you won’t be able to get the same distance for 2 miles in each city , in paris for example 2 miles will show up as 2miles = 1 inch , but when you scroll to nyc , yes that is a long scroll , the scale will suddenly change to 2 miles = 1,5 inch , and there is no way to escape this bug . too bad , now it is hard to put 2 cities next to eachother from different maps to see the size of a town compare to another city.

]]> By: tobias http://laudontech.com/GISBlog/?p=28&cpage=1#comment-183 tobias Tue, 19 May 2009 08:45:37 +0000 http://laudontech.com/GISBlog/?p=28#comment-183 Take a look at the conversion table from ESRI: http://blogs.esri.com/Support/blogs/mappingcenter/archive/2009/03/19/How-can-you-tell-what-map-scales-are-shown-for-online-maps_3F00_.aspx Take a look at the conversion table from ESRI:

http://blogs.esri.com/Support/blogs/mappingcenter/archive/2009/03/19/How-can-you-tell-what-map-scales-are-shown-for-online-maps_3F00_.aspx

]]> By: Will http://laudontech.com/GISBlog/?p=28&cpage=1#comment-179 Will Mon, 16 Feb 2009 02:00:49 +0000 http://laudontech.com/GISBlog/?p=28#comment-179 As Morton pointed out, these numbers are pretty much useless. What is needed is "meters per pixel" at every zoom level. That's what the dynamic scale bar is showing. As Morton pointed out, these numbers are pretty much useless. What is needed is “meters per pixel” at every zoom level. That’s what the dynamic scale bar is showing.

]]> By: geofumadas » Blog Archive » Google Maps, ahora con curvas de nivel http://laudontech.com/GISBlog/?p=28&cpage=1#comment-157 geofumadas » Blog Archive » Google Maps, ahora con curvas de nivel Thu, 03 Apr 2008 04:04:36 +0000 http://laudontech.com/GISBlog/?p=28#comment-157 [...] de 2x a 17x, a la verdad eso no se puede asociar a una escala fácilmente, ya algunos han hecho sus aproximaciones, llegando a buenos niveles de [...] [...] de 2x a 17x, a la verdad eso no se puede asociar a una escala fácilmente, ya algunos han hecho sus aproximaciones, llegando a buenos niveles de [...]

]]> By: Google Maps, ahora con curvas de nivel http://laudontech.com/GISBlog/?p=28&cpage=1#comment-156 Google Maps, ahora con curvas de nivel Thu, 03 Apr 2008 03:58:29 +0000 http://laudontech.com/GISBlog/?p=28#comment-156 [...] de 2x a 17x, a la verdad eso no se puede asociar a una escala fácilmente, ya algunos han hecho sus aproximaciones, llegando a buenos niveles de [...] [...] de 2x a 17x, a la verdad eso no se puede asociar a una escala fácilmente, ya algunos han hecho sus aproximaciones, llegando a buenos niveles de [...]

]]> By: Helsted http://laudontech.com/GISBlog/?p=28&cpage=1#comment-152 Helsted Mon, 25 Feb 2008 10:02:13 +0000 http://laudontech.com/GISBlog/?p=28#comment-152 I've made some calculations, and I do not reach the same scale values. I use the tilling scheme provided by google to calculate envelope's in each zoom level. (Remember that Google Maps use Mercator meters) Here are my results: Zoom level 0 1:20088000.56607700 meters Zoom level 1 1:10044000.28303850 meters Zoom level 2 1:5022000.14151925 meters Zoom level 3 1:2511000.07075963 meters Zoom level 4 1:1255500.03537981 meters Zoom level 5 1:627750.01768991 meters Zoom level 6 1:313875.00884495 meters Zoom level 7 1:156937.50442248 meters Zoom level 8 1:78468.75221124 meters Zoom level 9 1:39234.37610562 meters Zoom level 10 1:19617.18805281 meters Zoom level 11 1:9808.59402640 meters Zoom level 12 1:4909.29701320 meters Zoom level 13 1:2452.14850660 meters Zoom level 14 1:1226.07425330 meters Zoom level 15 1:613.03712665 meters Zoom level 16 1:306.51856332 meters Zoom level 17 1:153.25928166 meters Zoom level 18 1:76.62964083 meters Zoom level 19 1:38.31482042 meters PS. you don't have to know these scale values to create a tiling scheme for ArcGIS Server :-) I’ve made some calculations, and I do not reach the same scale values.
I use the tilling scheme provided by google to calculate envelope’s in each zoom level.
(Remember that Google Maps use Mercator meters)

Here are my results:

Zoom level 0 1:20088000.56607700 meters
Zoom level 1 1:10044000.28303850 meters
Zoom level 2 1:5022000.14151925 meters
Zoom level 3 1:2511000.07075963 meters
Zoom level 4 1:1255500.03537981 meters
Zoom level 5 1:627750.01768991 meters
Zoom level 6 1:313875.00884495 meters
Zoom level 7 1:156937.50442248 meters
Zoom level 8 1:78468.75221124 meters
Zoom level 9 1:39234.37610562 meters
Zoom level 10 1:19617.18805281 meters
Zoom level 11 1:9808.59402640 meters
Zoom level 12 1:4909.29701320 meters
Zoom level 13 1:2452.14850660 meters
Zoom level 14 1:1226.07425330 meters
Zoom level 15 1:613.03712665 meters
Zoom level 16 1:306.51856332 meters
Zoom level 17 1:153.25928166 meters
Zoom level 18 1:76.62964083 meters
Zoom level 19 1:38.31482042 meters

PS. you don’t have to know these scale values to create a tiling scheme for ArcGIS Server :-)

]]> By: Ian http://laudontech.com/GISBlog/?p=28&cpage=1#comment-131 Ian Wed, 20 Feb 2008 12:27:21 +0000 http://laudontech.com/GISBlog/?p=28#comment-131 How about the width and height of the tiles per zoom level? And how do you determine the amount of rows and columns per zoom level? Anyone know? How about the width and height of the tiles per zoom level? And how do you determine the amount of rows and columns per zoom level? Anyone know?

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