of the Kiel Canal are not 500 meters. Take a look at the scale in the map bubble at the bottom of the OpenCPN
display its probably about 1:16000 which is equivalent to about 6000 meters on GE. I am not sure what TeraInCognita means by their zoom selection but 500 meters does not produce a chart at 500 meters. Go into GE and look at what the entrance to the Kiel looks like at 500 meters then try to zoom in on OpenCPN
to the same level, it will be very blurry.
This explains why when I selected 2000 meters the chart was so blurry the chart produced was at an equivalent height of 30,000 meters.