-------- Original Message --------
Subject: Re: Can world maps be centered on varying coordinates
Date: Mon, 25 Feb 2013 08:44:24 -0500 (EST)
From: Paige G Andrew <[log in to unmask]>
To: Air Photo Maps, GIS Forum - Map Librarianship <[log in to unmask]>

And from my end, I agree that the start/end line of longitude for this
map, and others like it, is 90 degrees. A world map can be created to be
centered on whichever line of longitude the cartographer cares to use.
As a cataloger however, for consistency's sake and more specifically to
indicate to someone reading a set of coordinates, what was decided long
ago is a specific coordinate set that says "this is a world map", which
is what I shared earlier.

You bring up an excellent point in this regard Mark in terms of then
needing to make some other choices regarding projection and how things
would "work" together in certain circumstances. So, following up on your
idea of making sure that the cataloger specifies what the true situation
for a title like this is, we can and should provide a specific note in
our record. An alternative, at the local level at least, would be to use
the MARC 300$a "other scale information" situation where one can provide
the scale first followed by a brief statement such as "[centered on
XXX]" which would then up the "prominence" factor in that that
information would be tethered to the scale information and also appear
in most cases in both a brief record and farther up in a full record for
the item.

Paige

----- Original Message -----
From: "Angie Cope, American Geographical Society Library, UW Milwaukee"
<[log in to unmask]>
To: [log in to unmask]
Sent: Monday, February 25, 2013 8:30:52 AM
Subject: Re: Can world maps be centered on varying coordinates

-------- Original Message --------
Subject: Re: Can world maps be centered on varying coordinates
Date: Sat, 23 Feb 2013 00:30:41 +0000
From: Mark Jackson <[log in to unmask]>
To: Maps, Air Photo, GIS Forum - Map Librarianship <[log in to unmask]>

I should note that I am not a cataloger and have very little to do with
that so I didn't read into it that deep. I was just pointing out that
the map did indeed go from -90° to -90° (+270°). I can see Paige's point
about using +180° to -180° to indicate that it is a global coverage, but
there needs to be someplace that the actual extents of the map are noted
prominently if that is the case. If for instance I want an old map of
the seas to digitize and drop into the background of a map I'm creating
in a GIS then this map isn't going to work very well.  I'd have to
change my projection to match this map or cut it in pieces so it will
align with my other data that is in a more traditional 0°,0° origin and
extending to 180° east and west.

--
Dr. Mark Jackson
Brigham Young University
Geography, Geology, Civil Engineering, & Technology Librarian
2420 HBLL
Provo UT 84602
801.422.9753
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On Feb 22, 2013, at 12:56 PM, "Angie Cope, American Geographical Society
Library,              UW
   Milwaukee" <[log in to unmask]>
   wrote:

> -------- Original Message --------
> Subject: Re: [MAPS-L] Can world maps be centered on varying coordinates
> Date: Fri, 22 Feb 2013 13:55:22 -0600
> From: Robert T Wyatt <[log in to unmask]>
> Reply-To: [log in to unmask]
> To: Maps, Air Photo, GIS Forum - Map Librarianship <[log in to unmask]>
>
>
> Angie Cope, American Geographical Society Library, UW Milwaukee wrote:
>> (W 90--E 90/N 90--S 90)
>
> To me, the issue is that W 90 is not congruent to E 90, it would be E
> 270, which isn't used and which I expect to be the reason W 90 was used
> for both margins.
>
> Unfortunately I don't have a better proposal but I have been intrigued
> by the responses.
>
>
> Robert T Wyatt