----- Original Message -----=20 From: juanse barros=20 To: MapInfo=20 Sent: Thursday, April 19, 2001 7:22 PM Subject: RV: Conversion error PSAD56 to SAD69 Hi there Any one (cliff) have any experience changing datum from Provisional = South American Datum of 1956 to South American Datum of 1969?. I have some data on PSAD56 and some data on SAD69 that I have digitized = separately each one with MI set to receive the data accordingly. I though that if I put both data set (they are proyected to Universal = Tranverse Mercator - UTM) in the same map, lines will match. How ever I have some 85 metres of shift between both data set. I have = tryied to reproyect one of them to the other proyection/datum by saving = copy as (with new parametres) but thing do not impove. Any hints? Juanse Temuko Chile PS: The Psad56 is not in the proyection file for UTM only for lat/long. = I have defined the proyection as "UTM Zone 18, Southern Hemisphere (SAD 56)", 8, 82, 7, -75, 0, 0.9996, = 500000, 10000000 To get both data set close together I have tryed different things, with = the closes one being to change the scale factor of PSAD56 to 0.99958 and = I get quite close. Only remains a small shift east-west of some 14 = metres. I know this is not the rigth approach but..... ~~~~~~~~~~~~ List Sponsor ~~~~~~~~~~~~ Digital GEO data for 125 countries LAND INFO International produces digital geographic data for over 125 countries. DEMs, satellite imagery, topo maps, vector map layers, flood maps, and more. Visit http://www.landinfo.com/indexdm1.htm and let our specialists find the right solution. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ _______________________________________________________________________ List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, send e-mail to [EMAIL PROTECTED] and put "unsubscribe MapInfo-L" in the message body.
