[HOT] [info-hotosm] Reference Project #1030 Nepal Earthquake

Steve Bower sbower at gmavt.net
Sat May 9 18:03:22 UTC 2015


Spring,
When I talk about "moving the imagery" that is only to align it with Bing
imagery as I work in a very localized area, in order to confirm that the
features are (roughly) correctly located, relative to Bing. It does not
change the geo-referencing of the underlying data for other users - it is
only revising it for my display. I expect that how you understood it, but
in case that wasn't clear.

I haven't personally digitized anything from the DG imagery. I have only
used it to help with interpretation where the Bing imagery is poor (low res
or cloudy). But others may be locating features from the DG imagery -
hopefully only experienced mappers with careful reference to better
geo-rectified imagery ("hopefully" being the aspect that gives us all
concern, of course).

I fully agree this is not "best practice" for digital mapping - it's "best
available" within resource constraints for crisis response.

By the way, you may already be very familiar with this, but the elevation
aspect of ortho-rectification is described here (see image at top-right):
http://en.wikipedia.org/wiki/Orthophoto. Or see the first image in this
page: http://www.kevinroper.org/portfolio/ . These explain why the more
severe off-nadir angle causes greater location distortion, more difficult
to correct for.



On Sat, May 9, 2015 at 10:30 AM, Kevin Bullock <kbullock at digitalglobe.com>
wrote:

> >>Does Digital Globe supply Bing images?  Just curious, they are always
> referred to as different products.
>
> Yes, Microsoft licenses DigitalGlobe imagery for many parts of the world,
> you’ll notice the attribution in the Bing Maps platform. In various
> threads, I’ve seen Bing imagery “versus” DigitalGlobe imagery, and that is
> usually a contradiction. The proper way of characterizing it is:
> DigitalGlobe imagery through the Bing platform versus DigitalGlobe imagery
> being made available during this crisis.
> https://www.digitalglobe.com/partners/platform-partners/microsoft
>
> Cheers, Kevin
>
>
> This electronic communication and any attachments may contain confidential
> and proprietary information of DigitalGlobe, Inc. If you are not the
> intended recipient, or an agent or employee responsible for delivering this
> communication to the intended recipient, or if you have received this
> communication in error, please do not print, copy, retransmit, disseminate
> or otherwise use the information. Please indicate to the sender that you
> have received this communication in error, and delete the copy you received.
>
> DigitalGlobe reserves the right to monitor any electronic communication
> sent or received by its employees, agents or representatives.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/hot/attachments/20150509/c56e66c5/attachment.html>


More information about the HOT mailing list