I have (god help me) been tasked with the task of doing an areal survey of Stratford upon avon.
The background can be seen here. Basically (at the last draft) it involves taking photos out the side window of a Cessna with a 12mp DSLR while flying 5 concentric circuits round the town. Due to weather, it could be as soon as Thursday that I fly, so i need help fairly quickly. Now I'm an experienced photographer, but I'm never taken photos from a plane before, i need advice form people that have done this before. Questions: Ortho rectification -- how exactly is it done, and is there anything that i need to look out for when taking the photos -- it is really critical to me that i know what's going on before the flight. Specifically how much overlap do the images need? from my panoramic experience, i always take at least 50% overlap, so if any image fails, i have others that can fill in the gaps, it also helps with automatic alignment tools. are such tools available for aerial work, or is it just a monkey dragging image corners onto a map? How critical are lens characteristics? I have 2 nice prime lenses one of which has a known close to flat field. I also have a zoom lens that would be perfect, (Zeiss 16-80) it's sharp but it's field is not perfectly flat, and being a zoom, it's length is not perfectly repeatable (although i do plan on using it at it's extreme long end mostly) It would allow me to get wider shots when needed. I plan on taking photos looking outward towards the horizon from the outer edge of the survey area, is this useful/advisable/problematic? Is there any problem when rectifying of images that are wide enough to go above the horizon, I imagine this would break some of the maths. Any other tips? Thanks, JR
_______________________________________________ talk mailing list [email protected] http://openaerialmap.org/mailman/listinfo/talk_openaerialmap.org
