Dear Bob, The Survey of India (British Royal Engineers) established the INDIA Zones IIB, IIIB, and IVB in 1905 for the Burma area. The grids are based on the Lambert Conical Orthomorphic projection defined with a Latitude of Origin and a Scale Factor at Origin. Although all three of these British Grids were secant Lamberts (2 standard parallels), the actual standard parallels were never published. Therefore, your software MUST be able to accommodate the British definition of a Lambert Zone based on the parameters I mentioned above. Very few packages do that , Map-Info is not one of them. They implemented the American (and French) definition, so you're out of luck. Equations to convert from British definition parameters to American definition parameters do not exist. It is an iterative solution that solves for convergence of scale factor being equal to unity at particular parallels of latitude. (The "other" direction has closed equations and is a simple thing to do.)
Of course, the ellipsoid of reference was the Everest 1830. That's the answer; sorry that you're probably out of luck. Regards, Clifford J. Mugnier ([EMAIL PROTECTED]) Chief of Geodesy Center for GeoInformatics LOUISIANA STATE UNIVERSITY Dept. of Civil Engineering CEBA 3223A Baton Rouge, LA 70810 Facsimiile (225) 578-8652 Voice (225) 578-8536 Beep (504) 382-4371 -------------------------------------------------------- http://www.ASPRS.org/resources.html http://www.ce.LSU.edu/~mugnier/ -------------------------------------------------------- Hi mappers. I am using a series of maps for GIS work, but there is no indication of what projection they use. They are called the Burma One Inch series, inch to the mile, largely created or modified by British army surveyors during World War II. I assume there would have been a consistent projection used by cartographers at the time, especially in the British Army. I'm just using basic Lat/Long as projection at present. Bob Hudson Archaeology Department, University of Sydney, Australia. http://acl.arts.usyd.edu.au/~hudson/bobhpage.htm --------------------------------------------------------------------- List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 5372
