How would I georeference the image below. All I have is the information provided on the Image below (showing easting and northings). I am focusing on Georeferencing the section In red. Once Georeferenced I was going to create a polygon shape around the area to act as the new shapefile. I am using ArcGIS V10.6.1
The only Lat and Long I have is for the center of the area
I need the area to be in the black box in the image below
Am I Georeferencing correctly as seen below?
The problem is that you know the longitude of the first tick mark on the top, but not the latitude. Its a bit higher than 54:20N but you don't know how much. The same problem occurs for the latitude markers on the sides.
But if you connect the tick markers you can then get the lat and long of the intersections. Here's how it looks with some horizontal and vertical rulers added using GIMP:
Now if I add points at those intersections I know their lat-long and I can use the georeferencer as normal. Note this assumes the lines of latitude and longitude are straight and at right angles - which might not be true if this is a something like a conical map projection, but then you'd probably notice that the rectangles of the grid created weren't true rectangles.
54°20'N means 54 degrees and 20 minutes north of the equator. A minute is 1/60th part of a degree, so 20 minutes is one third of a degree. In decimal, that is 0.3333 recurring. So in decimal degrees that latitude is 53.3333. I don't know if the georeferencing software you plan to use wants you to type degrees and minutes or decimal degrees, but if its decimal degrees you need to enter 53.3333 and not 53.20.
Commented
Aug 24, 2021 at 8:42
After research I have found that OSPAR have a marine protected areas network with downloadable shapefiles.