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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Mikael,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Many thanks you could be right, I had noticed that the lat_ts parameter was not present in any of the other “typical” Mercator Proj4 strings I came across – I will give this a try and let you know.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Geoff<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Mikael Rittri [mailto:Mikael.Rittri@carmenta.com] <br><b>Sent:</b> Thursday, July 19, 2012 10:41 AM<br><b>To:</b> <geoff@tritonimaginginc.com>; PROJ.4 and general ProjectionsDiscussions<br><b>Cc:</b> proj@lists.maptools.org; Howard Unkeles<br><b>Subject:</b> Re: [Proj] Bad Mercator Projection string?<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><br>I don't know what the trouble is, but maybe GeoTIFF doesn't support Mercator with<o:p></o:p></p></div><div><p class=MsoNormal>a lat_ts parameter (latitude of true scale). If so, you can try to use a scale factor instead. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>That is, replace your<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> +lat_ts=41.5<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>by<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal> +k_0=0.750058844766239<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>This will give you an equivalent definition, and maybe it will work better. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Best regards,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Mikael Rittri<o:p></o:p></p></div><div><p class=MsoNormal>Carmenta<o:p></o:p></p></div><div><p class=MsoNormal>Sweden<o:p></o:p></p></div><div><p class=MsoNormal><a href="http://www.carmenta.com">http://www.carmenta.com</a><o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><br>18 jul 2012 kl. 19:16 skrev "Geoff Shipton" <<a href="mailto:geoff@tritonimaginginc.com">geoff@tritonimaginginc.com</a>>:<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Hello everyone,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>We “inherited” this Proj4 string from a previous product – it has always seemed to work but we are having problems using it with gdalwarp, the warped .tif image looks valid but has errors in the TIF tags. If anybody has any idea what’s wrong I would be grateful. Comparing it with other Mercator Proj4 strings it looks a bit simple…<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Here’s the string:<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>+proj=merc +datum=WGS84 +lon_0=0 +lat_ts=41.5 +x_0=0 +y_0=2000000<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I am not a geodesist, be gentle.<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Many thanks,<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Geoff Shipton,<br>Triton Imaging Inc.<br>Customer Support.<br>Capitola CA.<br><a href="mailto:geoff@tritonimaginginc.com">geoff@tritonimaginginc.com</a><br><br><span style='font-size:8.0pt'>The information contained in this message may be privileged or confidential information intended solely for the use of the addressee(s). Any views or opinions presented in this communication do not necessarily represent those of Triton Imaging, Inc. If the reader of this message is not the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please immediately notify me and you are hereby instructed to delete all electronic copies and destroy all printed copies.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div></div></blockquote><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>_______________________________________________<br>Proj mailing list<br><a href="mailto:Proj@lists.maptools.org">Proj@lists.maptools.org</a><br><a href="http://lists.maptools.org/mailman/listinfo/proj">http://lists.maptools.org/mailman/listinfo/proj</a><o:p></o:p></p></div></blockquote></div></body></html>