January 22, 200422 yr Hi all,I'm working on a Italian area. This area is about 100 x 100 km square. I've a big texture (1Gb in BMP format) to place on FS2004 terrain. I use Photo Scenery Maker to create the scenery. I've placed this texture with the "2 point calibration" option.The problem is this: once the scenery is created, only the areas near the "2 points of calibration" are in the exact place. Others not! I think this error is caused by the spherical geometry of planet Earth. With big textures, the error of the coordinates is too big!Anyone knows how to resolve this problem or I have to place meny small textures?Thank you very much!Maurizio (Italy)
January 22, 200422 yr Sounds like your photo is not georefereneced, so not really an orthophoto, just an aerial photo.Is there an option to use more than 2 points to calibrate? If not you may be out of luck unless you want to invest in some really expensive software.Other option might be to break the large image down into 10 or 20 smaller images.Matt
January 22, 200422 yr Thank you very much! Now I know the exact difference of an aeral photo and a georeferenced photo. I've always believed that the aerial photos were georeferenced, but it isn't!(Sorry for my bad english)But, where can I download or buy georeferenced photos of a region in the World? For example for Italy?What are this expensive softwares that georeferences my aerial photos?RegardsMaurizio (Italy)
January 26, 200422 yr Its not very easy to find good georeferenced aerial photos, and they are usually very expensive, especially for color.Just search yahoo or google for "georeference aerial" and you can find some programs that will do it. Or you can use Photoshop or good photo editing software by overlaying your aerial over a good map that you know is georeferenced. Then strech your aerial to fit the georeferenced map.Matt
January 27, 200422 yr Hello,Here In Portugal we have one Institute that is responsable for producing ortophotos and aerial photos: Portuguese Geographic Institute-IGPWe also have several Municipalities (I don't kow a better translation of munic
January 27, 200422 yr Author Commercial Member Don't give up too soon -- the entire photoreal scenery which I distribute on the Godzone magazine began as normal aerial photos, so it is possible to get this to work. You just need smaller chunks, which you can calibrate individually. I use areas of 30x40kms, which is the size the images are supplied in, but this gives a good result. Joining two adjacent areas is relatively easy, joining four is more difficult! The largest area I've make is 120 x 80 kms, which is 6 separate projects.I wouldn't attempt this without knowing the scale -- you need at least one known value, or it would be just too difficult. I always size the image before I begin -- with Terrabuilder (and i assume Photo Scenery Maker is the same) using the two-point calibration means that Resample.exe gets to resize the image, which doesn't give a good result. Resizing it correctly before you start means that Resample won't have to change the image at all. A single point calibration works just as well, but there is a lot of work to do first with non-georeferenced images -- ideally each corner point needs to be moved slightly, but I just rotate each image slightly, which gives a close fit. The rotation is normally based on overlaying the aerial image (or a screenshot of it, to keep the size down) over a screenshot from the simulator, and getting any reference points to align. Rivers, lakes and coastlines are best for alignment, airports work ok except when they are not in the proper place!I've written a few tutorials on this, but because they are not of enough general interest they are not online, they were published in the Godzone scenery magazines, along with the resulting scenery. I normally wouldn't suggest this, but it may be useful to purchase the magazines:)
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