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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi all,<o:p></o:p></p><p class=MsoNormal>New to PROJ, using 7.1.1 on linux, still trying to learn the basics.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So it seems to me that one should get the same results from<o:p></o:p></p><p class=MsoNormal>cs2cs +init=<crs1> +to +init=<crs2> | cs2cs +init=<crs2> +to +init=<crs3><o:p></o:p></p><p class=MsoNormal>as<o:p></o:p></p><p class=MsoNormal>cs2cs +init=<crs1> +to +init=<crs3><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>i.e. a transform to an intermediate CRS shouldn’t affect the final result, but it seems in my case at least it does. <o:p></o:p></p><p class=MsoNormal>E.g.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>cs2cs -d 6 +init=epsg:4326 +to +init=epsg:7856+5711<o:p></o:p></p><p class=MsoNormal>151 -33 5<o:p></o:p></p><p class=MsoNormal>313152.777214 6346936.495810 -20.742001<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>vs.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>cs2cs -d 6 +init=epsg:4326 +to +init=epsg:32756 | cs2cs -d 6 +init=epsg:32756 +to +init=epsg:7856+5711<o:p></o:p></p><p class=MsoNormal>151 -33 5<o:p></o:p></p><p class=MsoNormal>313153.271255 6346937.914960 -20.853001<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Close, but off by about 1.7m. How would I know which one is correct, and why are they different?<o:p></o:p></p><p class=MsoNormal>I must be missing something…thanks!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div><div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br />
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