Building maps for existing (published) settings
I wanted to get some feedback or discussion started around the idea of producing maps within existing (i.e. published) campaign settings. My specific thoughts are:
1) is there any reason to believe that mapping out a specific area of an existing work would be considered copyright infringement?
2) what are the social (i.e. "credibility") implications of working by building on top of established work?
I have a specific example: I'm running a 1st edition D&D Forgotten Realms game (not because I'm an OSRIC adherent, I just felt like doing it for nostalgia) and I've created some really nice alterations of area maps by emulating existing map styles and building on top of them for the campaign. Would posting that kind of work alienate other cartographer/artists here? Would it be in poor taste? If so, why?