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Home - General / All posts - Pseudo mercator (EPSG: 3857) in Manifold 8
philw
101 post(s)
#11-Oct-18 04:07

Can someone point me to the correct projection in Manifold 8 for EPSG 3857 - Pseudo mercator? A QGIS export with this projection is not importing to M8 with the projection info and for the life of me I can not find the correct one to apply. Is there a way to find the EPSG number for projections in M8?

hugh
200 post(s)
#11-Oct-18 06:15

should be this:

Attachments:
3857in8.jpg

philw
101 post(s)
#11-Oct-18 06:54

I tried the standard Mercator but the image is projected about 4.5 km north of its true position. It is correctly positioned in QGIS as other layers overlay it properly. Anyone with thoughts on what the issue might be?

geozap
264 post(s)
#11-Oct-18 07:34

PseudoMercator is not just Mercator with WGS84. Have a look here: https://epsg.io/3857 and here https://en.wikipedia.org/wiki/Web_Mercator_projection

tjhb
10,094 post(s)
#11-Oct-18 07:41

Hugh's suggestion is correct. You must use datum WGS84 Auto, as he says, which as geozap says is different from standard WGS84.

philw
101 post(s)
#11-Oct-18 08:47

Ahhh attention to detail! You are right, changing it from WGS84 (as it was imported) to WGS84(Auto) worked. As a matter of interest, what is the difference? Confusing when you look at the imported file and it seems to have the correct datum... but not quite.

tjhb
10,094 post(s)
#11-Oct-18 08:57

The difference is that Google pretends that the Earth is a sphere, with the correct equatorial radius applied incorrectly for the poles.

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