Converting Shapefile to Non-Standard Projection: Seeking Guidance

[nexusiceland]

I've encountered a mapping challenge that delves into the realm of custom projections, and I'm in need of some expert advice.  I'm working with a shapefile that needs to be projected into a custom coordinate system which, unfortunately, doesn't have a corresponding EPSG code. The issue arises when attempting to align this custom projection with EPSG projections within ArcMap. The custom projection is not available in the EPSG database. I've encountered challenges matching it with existing EPSG projections in ArcMap.How can I successfully project a shapefile to a custom coordinate system that lacks an EPSG code?  Are there alternative methods or tools within ArcMap that could facilitate this conversion? Has anyone faced a similar situation, and if so, what strategies were employed to overcome this mapping hurdle?

[BojanŠavrič]

Hi @nexusiceland,
Using custom projected coordinate system and aligning it with existing definition depends on the custom definition. Does you definition also have a custom geographic coordinate system? If it does, you have to first use the Create Custom Geographic Transformation tool to define a transformation that will align your custom geographic coordinate system with existing definition. After that, you can use Project tool to convert your data to your custom definition, by selecting it as an output coordinate system. Make sure you also select an appropriate transformation path in the tool, using previously defined custom geographic transformation.