2008/11/30 Ethan Alpert <span dir="ltr"><<a href="mailto:ealpert@digitalglobe.com">ealpert@digitalglobe.com</a>></span><br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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How come no ones questioning the accuracy of the sensors that collected<br>
the imagery in Google Maps? I happen to know that satellite imagery is<br>
not very accurate unless you have decent ground control and a DEM. Even<br>
then it's not that great. It seems pointless to try to determine<br>
accuracy in Google Maps unless you understand where the imagery came<br>
from and how it was produced.</blockquote><div><br><br>At least where I live (Copenhagen, Denmark), the high resolution<br>layers of Google Maps come from very high precision<br>photogrametrically derived orthophotos, which should certainly<br>
have an accuracy way better than the "few meters with occational<br>ten meter blunders" quoted earlier in this thread. <br><br></div></div>