PRJ line for Merchich Morocco EPSG26191
Gentreau
Hi, I hope someone here can clear this up for me.
I need to add a projection for EPSG:26191 Merchich North Morocco.
When I look it up at http://spatialreference.org/ref/epsg/26191/ I see that it’s a Lambert Conformal Conic Projection but the information provided is incomplete to create a MapInfo PRJ entry.
According to the documentation I have, I need two standard parallels and the data provided by the link above does not seem to be consistent.
Ex. The bounds are given as -9.7500, 31.5000, -1.0100, 35.9500 but when I look at the details I see: PARAMETER["latitude_of_origin",33.3],PARAMETER["central_meridian",-5.4],
All help gratefully received.
Confused of France......
David R Sherrod
Gentreau, it's not like you to be confused.
The standard parallels will vary depending on which zone of the Merich you are in---or so I surmise from the following info I plucked from a web search.
Can you determine the zone?
Unclear to me which ellipsoid is correct. EPSG:26191 Merchich North Morocco seems to be "Clarke 1880, modified for IGN." You may need to track this carefully in order to get good fit. Documentation in older versions of MI-Pro was an appendix, "Defining custom datums/ Datum conversions."
[Rest of this e-letter is pasted in from website.]
https://getsatisfaction.com/plexearth/topics/projection_systems_in_morocco
*The map projection used in Morocco is the projection of Lambert Conformal Conic
*Morocco is divided into 4 zones (1, 2, 3 and 4)
Projection Parameters Lambert Northern Morocco (ZONE 1):
Origin Latitude: 33 ° 18 '0 ".00 North (33 ° .3)
Origin Longitude: 5 ° 24 '0 "West (5 o .4)
1st standard parallel: 31 ° 43 '30 ".00 North (31 ° .725)
2nd standard parallel: 34 ° 51 '57 ".60 North (34 ° .866)
Constant X: 500000.00 m
Constant Y: 300000.00 m
Scale factor at origin: 0.999625769
Projection Parameters Lambert South Morocco (ZONE 2):
Origin Latitude: 29 ° 42 '0 ".00 North (29 ° .7)
Origin Longitude: 5 ° 24 '0 "West (5 o .4)
1st standard parallel: 28 ° 05 '52 ".80 North (28 ° .098)
2nd standard parallel: 31 ° 16 '30 ".00 North (31 ° .275)
Constant X: 500000.00 m
Constant Y: 300000.00 m
Scale factor at origin: 0.999615569
Projection Parameters Lambert Morocco Far South (ZONE 3):
Origin Latitude: 26 ° 06 '0 ".00 North
Origin Longitude: 5 ° 24 '0 ".00 West
1st standard parallel: 24o 29 '52 ".80 North
2nd standard parallel: 27o 41 '02 ".40 North
Constant X: 1200000.00 m
Constant Y: 400000.00 m
Scale factor at origin: 0.999616304
Projection Parameters Lambert Morocco Far Far South (AREA 4):
Origin Latitude: 22 ° 30 '0 ".00 North
Origin Longitude: 5 ° 24 '0 ".00 West
1st standard parallel: 20 ° 53 '52 ".80 North
2nd standard parallel: 24 ° 05 '02 ".40 North
Constant X: 1500000.00 m
Constant Y: 400000.00 m
Scale factor at origin: 0.999616437
-----------------------------------------
| From: | "Gentreau" <goo...@gentreau.com> |
| To: | <mapi...@googlegroups.com> |
| Date: | 07/31/2012 01:58 AM |
| Subject: | [MI-L] PRJ line for Merchich Morocco EPSG26191 |
| Sent by: | mapi...@googlegroups.com |
--
You received this message because you are subscribed to the
Google Groups "MapInfo-L" group.To post a message to this group,
send
email to mapi...@googlegroups.com
To unsubscribe from this group, go to:
http://groups.google.com/group/mapinfo-l/subscribe?hl=en
For more options, information and links to MapInfo resources (searching
archives, feature requests, to visit our Wiki, visit the Welcome page at
http://groups.google.com/group/mapinfo-l?hl=en
Gentreau
Thanks David,
What I had not discovered, even after plenty of searching, was that the projection is split into 4 zones and that for zone1 (which I need) the first standard parallel is below the Latitude of Origin ......
It now works with the following line.
"Merchich - Maroc Nord EPSG-26191 (Zone 1)", 3, 55, 7, -5.4, 33.3, 31.725 , 34.866 , 500000, 300000
Gentreau.