Using a geotagged jpg in the WGS coordinate system

Question

I am working on software for mapping purposes and ran into a projection issue that is beyond my knowledge of GIS.

The software utilizes longitude latitude for all visual mapping in order to maintain consistency among all locations. This has worked great until I started to work with world files.

I have a world file that was exported in ArcMap using a UTM Zone 13N projection that looks like this:

Now I would like to add this image to the mapping software as a background (which is in WGS) so a projection conversion is necessary. After determining the image extent and location of the world file, then converting those points to WGS, I get the resulting extent defined by the rectangle:

Unfortunately, there is a slight tilt to the location where the jpg should be. Performing a transformation to the jpg is not trivial which leads me to the question:

Is there such a thing as having a world file that is compatible with the WGS coordinate system or are they only compatible with projected systems?

If they CAN be used in a geographical system, is there any easy way to handle the transformation (as opposed to pixel by pixel)?

Answer 1

Unless the data is near the center of the zone, longitude lines, and to a lesser extent, latitude lines are tilted toward the central meridian. When displaying latitude-longitude values, they're treated as if they are square, thus the tilt.

You might be able to 'rebox' your rectangle to remove the tilt. By rebox, I mean that you should separately project all four corners from UTM to WGS84, then take the minimum and maximum values and use those instead.

Answer 2

To put it very simple, projections in general have distortion. When we use a projection specific to a Zone, we minimize the distortion for that Zone. If you want to use a diferrent projection you have to reproject to "match the distortion". (well you don't actually match distortions you match the parameters that cause the distortion)

For the given problem you could georeference the image using coordinates from the image that you want to match. You need at least 4 control points and you can use the Georeferencing toolbar in ArcMap.