Thank you so much for your response! The resources you linked to were very useful. The Erdas paper is especially good. I never heard of MapAnalyst. I will have to give it a try.
Unfortunately, the focal length of the camera is not on the photo border. The photo must be too old. Do you have any recommendations on what focal length I should try? It was taken in 1939 for the USDA Agricultural Adjustment Administration. If it would help, I could send the image file. It is about 7 mb in size. I was using photo2.image as part of the i.ortho.photo UI when I was having the problems. It may be because I am using GIS-Knoppix. If I use GIMP to measure the fiducial mark coordinates, do I still need to use photo2.image or do I just use photo.camera? Thanks! Shaun On Sun, Apr 6, 2008 at 6:18 AM, Maciej Sieczka <[EMAIL PROTECTED]> wrote: > Shaun & Melissa Busler pisze: > > 1) When is i.ortho.photo going to be available for the Windows binaries? > > > > Dunno. It currently depend on X displays, not easily portable to else than > Unix. > > 2) The historic aerial photos do not have camera calibration files. I > > have > > searched all over and they do not seem to exist anymore. Is there a way > > to > > orthorectify the images without the camera calibration files? Can I > > make > > some assumptions? If so, what parameters should I enter? > > > > If the DPI at which photos have been scanned is known to you, you can > measure the principal point and fiducial marks coordinates in any image > editing software, like GIMP. Interior orientation results will depend on > how close is the geometry of the image plane to the geometry of camera's > optical system, and if/how the photo scan is distorted. > > Idea, not tested: you might try using software like MapAnalyst [1] to > asses the distortion of the image, which can help you guessing genuine > fiducial marks coordinates. > > Then you need the focal length. It often is present on the photo border. > Or guess it :). > > 3) When I tried using photo.2image, I was not prompted with "Look ok? > > (Y/N)" so I was not able to mark the fiducials. > > > > photo.2image is not supposed to be used standalone. i.ortho.photo is the > UI for photo.2image & friends. > > There's plenty of info you might find usefull on the net. eg. [2] [3]. > > [1]http://mapanalyst.cartography.ch > [2]http://support.erdas.com/focus3/files/Aerial_photo.pdf > [3] > http://www.pcigeomatics.com/services/support_center/faqs/oe_general_v10.html#no_fiducial >
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