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This question already has an answer here:

Is there any tool or any tutorial which would help me to figure out CRS (coordinate reference system) from related information?

In my particular case I know only the system is in meters, has origin (probably of zone) at E 91°30' and N 50°20' (not 100% sure about exactly 50°20') and it is presumably commonly used in Russia.

I would be glad for general solution if any.

marked as duplicate by Andre Silva, Community Nov 22 '16 at 11:41

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My preferred solution is to build a custom CRS in QGIS, and test if sample coordinate points are placed correctly compared to Openstreetmap or Google imagery from the openlayers plugin.

In Russia, Gauss-Krüger transverse mercator based on the Krassnowsky ellipsoid is common use. The projections named Pulkovo are usually 3 or 6 degrees wide, with a false Easting of 500000m to the central meridian. Some CRS put the zone number before the false Easting, like 16500000 for zone 16 arond the 48° meridian.

False Northing is not used, perhaps some leading numbers are simply stripped of for the local coordinates.

  • + 1 for tips on Russian projections, thank you. I will probably have to make custom projection then with false Northing in this particular case. Not sure about starting directly with custom CRS if it is not really obvious. I guess in many cases it is better to find few most probable CRS variations and check them first. In QGIS it is really easy to switch between them and as you wrote compare to Openstreetmap or Google imagery etc. – Miro Oct 21 '14 at 7:05
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Based on Identifying Coordinate System of Shapefile when Unknown? it directed me to a tool which is very helpful to find relevant CRS which is exactly I was hoping for:

http://www.epsg-registry.org/

The result in my case: enter image description here

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I recommend ProjFinder. The principle is "zoom on the place you are looking for and the tool will provide the supposed projections".

You can also use epsg.io and search Russia to sort out possible projections

  • ProjFinder looks great though it doesn't contain projections which I got when searching through epsg-registry.org and actually these were the ones I wanted in my particular case. epsg.io looks awesome, the only thing is I can't figure out if/how is possible to search through coordinates. – Miro Oct 21 '14 at 6:54
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I also used Projfinder and I found it is very useful.

But asking the producer is the best.

I worked on a project in South Africa, I found a suitable CRS but after few weeks the customer gave me the name of the right one, and it was different. Probably in Projectfinder is not available a full list of CRS like as in www.epsg-registry.org

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