Expedition Expedition Navigation Software

You are not logged in. Would you like to login or register?

4/02/2021 11:06 am  #1

Zooming Issues with C-Map Charts

We've had some issues with the Dutch Coast Guard regarding the 500 mtr/0.27 Nm keeping clear distance from the Q13a production platform off the Dutch Coast at position 052 11.5N, 004 8.17E.

Problem is that the 500 mtr distance circle on the C-Map chart is not zooming proportionally to the rest of the map. At closer zoom levels the circle diameter becomes much smaller than reality, so there is the risk of getting too close to the platform. The Dutch Coast Guard is monitoring AIS tracks of sailing vessels in the vicinity, as I've found out unfortunately. Zooming out of a few levels brings back the correct distance.

We've checked the C-Map zooming behavior in a certain French Navigation program of the same platform. This was found to be correct.

Expedition v. 11.8.6 for C-Map 4D



4/02/2021 11:42 am  #2

Re: Zooming Issues with C-Map Charts

Thanks. You you please email me any other details.

This is the circle on the C-Map chart, not a circle around the boat, mark etc drawn in Exp?

I can replicate this on the 4D chart. Unofrtunately, I don't have the detail in a MAX chart, which I presume is what the other software uses?

Do you have any paper charts? Is it correct on those?

Last edited by Nick (4/02/2021 11:47 am)


4/02/2021 11:56 am  #3

Re: Zooming Issues with C-Map Charts

I have done some more investigation and it seems to be something in the chart area (it also shows on the C-Map sample app). It seems correct in the level D data, but not in level E.

Interestingly, it appears correct on the web viewer (https://www.c-map.com/chartexplorer).

My 4D charting for Europe is old though. Before I contact C-Map, is your charting up to date? The web viewer suggests it has been fixed.

Last edited by Nick (4/02/2021 5:17 pm)


Board footera


Powered by Boardhost. Create a Free Forum

Interested in advertising here? Over a thousand active navigators and Expedition users visit this forum. Click here to contact the administrator.