[OSM-talk] Aerial Photographs (was: People's Map)

Keith Ng khensthoth at gmail.com
Thu Apr 16 05:18:03 BST 2009


I see. Thanks for the clarification.

On Thu, Apr 16, 2009 at 10:47 AM, Eric Wolf <ebwolf at gmail.com> wrote:

> RC airplanes aren't cheaper for two reasons:
>
> 1. RC airplanes (and any civilian-operated UAV) has significant flight
> restrictions - distance and altitude. Flying at low altitude (under
> 500 feet MSL), you end up with a higher spatial resolution but you
> have to stitch together many more images to cover the same extent as a
> single image taken from an aircraft flying at, say, 2000 feet MSL.
> Selecting good shots and correcting the imagery for hundreds of images
> ends up costing more than the difference in operating an RC plane and
> a regular aircraft.
>
> 2. RC airplanes crash - often - and they aren't cheap. Sure, regular
> airplanes are more expensive but they don't crash as often. A decent
> RC rig will set you back $1000+ - not counting the camera.
>
> I used balloons and blimps to do low-altitude aerial photography in my
> MS thesis. They are much cheaper than RC planes to operate because
> they don't crash (as easily). But you also don't have as much control.
> They work really well for taking low-altitude obliques for general
> documentation processes. But for creating a basemap of  aerial
> imagery, you need to get above the 500 ft MSL barrier put in place by
> the FAA. To do this, you have to be in an airplane piloted by a
> licensed pilot.
>
> Surprisingly, hiring a light aircraft - like the one used in this
> study - is not really all that expensive.
>
> -Eric
>
> -=--=---=----=----=---=--=-=--=---=----=---=--=-=-
> Eric B. Wolf                          720-209-6818
> USGS Geographer
> Center of Excellence in GIScience
> PhD Student
> CU-Boulder - Geography
>
>
>
>
> On Wed, Apr 15, 2009 at 6:25 PM, Keith Ng <khensthoth at gmail.com> wrote:
> > Couldn't the process of obtaining aerial photographs be made much cheaper
> > with RC planes? I am not sure if it would work but setting the RC plane
> on
> > auto pilot and attaching a camera with continuous shooting mode might
> make
> > the process simpler.
> >
> > Also refering to this link, a commentator said:"Just wanted to make it
> clear
> > that we (Pict'Earth) are willing to help anyone from the DIYDrones group
> to
> > get their UAV imagery processed and published in OAM, just let us know.
> If
> > you can fly with a logging GPS and a digicam, our Win32 software will get
> > you part of the way and we can help with the rest of the manual bits
> until
> > we get it truly automatic."
> >
> >
> > On Thu, Apr 16, 2009 at 4:06 AM, Blumpsy <blumpsy at yahoo.co.uk> wrote:
> >>
> >> There is an interesting paper from our dear friends over in Redmond:
> >>
> >> http://research.microsoft.com/apps/pubs/default.aspx?id=75312
> >>
> >>  From the article:
> >> "Our mission, in contrast, involved an ordinary four seat Cessna
> >> ($160/hour rental, including pilot), three feet of PVC pipe, a consumer
> >> digital camera ($300), and two people: one pilot and one to operate the
> >> camera shutter and change the batteries (Figure 2). In post-processing,
> >> we identified 25 ground reference pairs, and used 60 photos to produce a
> >> 208 megapixel image at a resolution of 0.15 m/pixel"
> >>
> >> The camera in Figure 2 looks exactly like the one I have sitting right
> >> next to me: a Canon Power Shot A640 with 10MP.
> >>
> >> I found it rather entertaining to have an operator to press the trigger
> >> and swap batteries. For this, there is surely a more elegant solution
> >> (PSU and gphoto2)
> >>
> >> Anyhow, maybe one or the other finds this interesting and inspiring.
> >>
> >> Cheers
> >>
> >> Blumpsy
> >>
> >>
> >> _______________________________________________
> >> talk mailing list
> >> talk at openstreetmap.org
> >> http://lists.openstreetmap.org/listinfo/talk
> >
> >
> > _______________________________________________
> > talk mailing list
> > talk at openstreetmap.org
> > http://lists.openstreetmap.org/listinfo/talk
> >
> >
>
> _______________________________________________
> talk mailing list
> talk at openstreetmap.org
> http://lists.openstreetmap.org/listinfo/talk
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk/attachments/20090416/da71bf1e/attachment.html>


More information about the talk mailing list