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1

Yes, they will be square in both projections! Breaking it down: UTM stands for Universal Transverse Mercator. From the Wikipedia article: The Universal Transverse Mercator (UTM) conformal projection ... i.e. UTM is "conformal." As for what "conformal" means, again from Wikipedia: Conformal, or orthomorphic, map projections preserve angles ...


1

There's a reason UTM projections don't extend to infinitive and engulf the whole globe. As you move further away from the UTM's central meridian the distortion becomes more and more apparent. In the case of a transverse Mercator projection the distortion, as its a conformal projection, is applied equally both in the X and Y axis, therefore your angles ...


2

The transverse Mercator Projection is conformal and preserves angles. So the square should still be a square. Area will change though.


5

Welcome to GIS SE! No worries here, you've got a shapefile whose coordinates subscribe to a State Plane Coordinate System, recorded in feet. The minimum bounding geometry coordinate you've retrieved can be thought of as the bottom-left bounding geometry corner relative to sort of an arbitrarily placed origin point on an XY plane. So, instead of 0,0, you ...


0

These are not strange coordinates. San Francisco's coordinate reference system is EPSG 2227 which is what is described by your .prj file. EPSG 2227 is in feet and not meters. To get UTM coordinates, you need to reproject to from EPSG2227 to UTM using something like QGIS, ARCGIS, or GDAL.


1

A very simple method is to put up a custom transverse mercator projection centered on the center of your study area: +proj=tmerc +lat_0=51.4 +lon_0=7 +k=1 +x_0=0 +y_0=0 +ellps=WGS84 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs This works for about +/- 15° of longitude. On longitudinal larger areas, a Lambert projection with one or two standard parallels would ...


1

The sample record you show is in projected coordinates and the two values for longitude and latitude listed in the Coordinate Reference System (CRS) are part of the parameters that defined the projection that was used, here a particular Transverse Mercator projection that is called "SVY21 / Singapore TM" and is centered near Singapore. You can use the latest ...


2

If you're looking for an established projection and you don't mind accuracy to around 2 meters, I would go with EPSG::3006 This assumes your data is in the SWEREF99 datum, but the difference between that datum and WGS84 is very slight.


3

While Save As ... works easily with vector data, it is not useful to do raster reprojections with it. Instead, use Raster -> Projections -> Warp for reprojection, or Raster -> Convert -> Translate ... for a different file format. For large files, it might be better to use the OSGEO4W Command Shell. You can use gdalwarp or gdal_translate with ...



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