hello,

i have some custom prepared maps of Black sea in non NT format. i would like to use them in gpsmap 421 which unfortunately is not supporting non NT format.
is there any possiblility to compile NT format map out from a non NT?
is there any other solution you could suggest?
or maybe there is a possibility to edit bluecharts g2?

unfortunately bluchart g2 for black sea is very innacurate, and only way to sail safely is either to make a lot of correction in this map, or to make a new one from scratch (but here we have the NT format problem)

thanks,
Alex