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Sev
462 post(s)
#17-Apr-19 08:09

I've got no doubt this has been covered before, but I can't find a reference to it anywhere.

When I "use projection" of an image server so I can view it in a map component, I mistakenly use the length (I) to do some calculations and text inserts......

As soon as I go to the drawing layer and use it's projection in the map, the distances are correct and all is good, but I can't see the imagery layer.

The tracker tool measures it correctly, which is great, but my question is whether there is any way to avoid this situation occurring even though the map component is using it's own projection?

Thanks in advance. Andrew.

ColinD

2,081 post(s)
#17-Apr-19 11:22

If I understand correctly, your image will likely be in pseudo Mercator, and so will your map. You can't assign say an MGA zone to that map and have the image showing. Just change to projection of your drawing to MGA whatever St George is 55 or 56? and it will overlay on the image map. It won't work the other way around.


Aussie Nature Shots

Sev
462 post(s)
#18-Apr-19 00:42

Thanks Colin, been a while!

My drawing projection is MGA (55), but I have to "use projection" of the image server to view. The problem occurs when I inadvertently do some measurements while the image is showing (pseudo Mercator), and the measurements are out significantly. This includes the object data when selected. I thought that the object data would reflect the projection the drawing it's in, but it seems to change to the projection in use.

I hope that makes sense.

Andrew.

ColinD

2,081 post(s)
#18-Apr-19 02:39

If your object drawing is definitely MGA (55) overlaid in the image server map the intrinsic fields of anything added to that drawing will be those for that projection. They won't change to pseudo Mercator. But if you use the distance tool it will give you the pseudo Mercator distances (it's not an equal distance projection) while in the map.


Aussie Nature Shots

Sev
462 post(s)
#19-Apr-19 06:53

You are correct (of course), I need to backtrack to see where I made a mistake with my process.

Thanks for clarifying this for me.

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