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I'm in need to find a suitable projections to measure correctly areas and lenghts for 2 areas of interest.

I want to measure both factors for: 1) First region Australia & New Zealand (1st region), 2) Second region - South East Asia defined as: Bornero, Honkong, Indonesia, Macao, Malyasia, Philipines, Singapoure, Thailand, Taiwan, Vietnam. (minlon: 94.89, minlat:-11.34, maxlong:141.056, maxlat:26.46)

In regards to Australia & New Zealand:

  1. Equal area projection: I could find two suitable projection to measure areas in Australia GDA94 / Australian Albers (EPSG:3577) and the Australian Albers (EPSG:17365). What about having a proper projection to measure areas at once in Australia and New Zeland? Is there any ready to use projection to do it or should I customize one of currently available, if so the question is how? More general question as nonGIS person: How does such projection measure area of relatively small shapes like shapes of the buildings in country? Does the area of interest the projection is applicable for somehow correspond to the size/ area of the object I would like to measure?

  2. Equidistance projection

Does the term distance correspond to the length in my understanding? For example I want to measure the length of each road I do have in the Australia's dataset I work with, but reading the definitions of equidstance projections I'm a litlle bit confused while in fact they're saying:

Equidistant conic projection - It has the useful property that distances along the meridians are proportionately correct, Equidistant conic projection - It has the useful properties that all points on the map are at proportionately correct distances from the center point.

What about measuring the lenght? Does the equdistance projection work for that, if not what would be the best option to go for region1/ region2 from my definition.

Thank you in advance for an answer, Dawid

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    Welcome to GIS SE. There are 2 questions here, so I suggest that you split your questions (use the edit button to remove the second part and copy it to a second question). – radouxju Jan 30 '14 at 14:19
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There are several global equal area projection that you could use for the two countries : sinusoidal projection and Eckert projection are. However, because you are far from greenwich, I recommend Berhmann cylindrical equal area to avoid large distortion. Note that you could make some nice custom Eckert or Sinusoidal projection simply placing the meridian of reference at the date line or at the middle of the extent between Australia and South East Asia.

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You could use the PostGIS Geography type and exact distance/area measurements on the spheroid. http://postgis.net/docs/using_postgis_dbmanagement.html#PostGIS_Geography

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