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Some success with a photo-textured scenery, and some qu...

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Hi all,I just got thru my first photoreal scenery (actually a learning prototype) with TerraBuilder Lite and I have some questions after going through this tedious process.First some screens. The scenery was put together with b&w USGS Aerial photos (8m/p) downloaded and stitched with USAPhotoMaps.exe. It is roughly a 33x24 Km area around KROA. All layed over top of FS Genesis high res mesh.I haven't learned how to paint the photos yet; so I just used ColorBMP.EXE to get going with something, and then hacked around with PSP8 to change things around (so it is quite ugly right now). http://forums.avsim.net/user_files/38120.jpghttp://forums.avsim.net/user_files/38121.jpghttp://forums.avsim.net/user_files/38122.jpgQ's:1) The last image shows a building in the upper right corner that is supposed to be a Mall. The Mall is actually the oval-ish blob just to the lower left of the building. When I do the 'Big' project I don't want that building to be there. Is there away to get rid of the building from the scenery?2) For anyone that has used a similar process to this. Is it normal to have the image of an airport not quite line up with the airport in FS? Ultimately, I want to make my own version of the airport; but where is the proper place to put it? Over the "old" FS airport or over the image in the photo?3) I spent a heck of a long time getting things lined up. I first tried to get the airport image to line up with the airport in FS. Until I realised that the ridges of the mountains were offset. So I went thru a long series of adjustments and image rotations (is it normal to have to rotate the image?). I think I either got the coord's wrong to begin with, or the photo is skewed or both. Is there an easy and fast way to get things lined up correctly , or is this going to be a strictly tedious trial-and-eror process?I got things "lined-up" as well as a I could, but there are still some problem areas.Well I'll shut up now. I need a long break before I attempt to do the "Real" project. Thanks in advanced for any response to my Q's.

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>1) The last image shows a building in the upper right corner>that is supposed to be a Mall. The Mall is actually the>oval-ish blob just to the lower left of the building. When I>do the 'Big' project I don't want that building to be there. >Is there away to get rid of the building from the scenery?You can make an exlcude and then you should get rid of that building. If you search this forum you will find a nice tutorial by Bob on how to make it.>2) For anyone that has used a similar process to this. Is it>normal to have the image of an airport not quite line up with>the airport in FS? Ultimately, I want to make my own version>of the airport; but where is the proper place to put it? Over>the "old" FS airport or over the image in the photo?From the airports I have made I know that the airport of MS are not always on the right location. So if you are sure that you have placed the photos accurate (do you have any coordinates for the photos or did you only line them up with the mesh?), I would place your airport at the location of the photos.

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>>You can make an exlcude and then you should get rid of that>building. If you search this forum you will find a nice>tutorial by Bob on how to make it.>Thanx. I'll check that out then.>>2) For anyone that has used a similar process to this. Is>it>>normal to have the image of an airport not quite line up>with>>the airport in FS? Ultimately, I want to make my own>version>>of the airport; but where is the proper place to put it? >Over>>the "old" FS airport or over the image in the photo?>>From the airports I have made I know that the airport of MS>are not always on the right location. So if you are sure that>you have placed the photos accurate (do you have any>coordinates for the photos or did you only line them up with>the mesh?), I would place your airport at the location of the>photos.Actually both. I (think) I had the coordinates of the photos correct but; I used USAPhotoMaps.exe to graphically figure the boundaries of the mosaic that it stitched together. I then input those numbers into the TerraScene wizard. When I looked at the result in FS, all I noticed was that the airport didn't line up - which sent me off into tedious fiddling land. I'm going to give it another go today, and really take a good look at the first pass this time. I'll worry about the airport later.I was alos thinking that maybe I'm trying to make "too big a picture". But I really want to get the whole valley in. Maybe for the final project, I'll stitch together mosaics from the 1m/p photos; but that sems like a monster job.Thanx again, arno.

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Hi Edwin.The images you are using are orthographic in nature... that's their projection. They are stretched to insure that 1 meter distance is the same no matter the matter the angle of measurement.Images for resample must be geographic in nature ( lat-long projection ) where lines of latitude and longitude are perpendicular and NS is vertical and EW is horizontal. Distance is distorted both according to angle and by the distance from the geographic poles. In other words, a meter is no longer a meter. Look at the distortion of Greenland in some maps, and you'll get an idea of the distotion of measurement in geographic-type projections.The sim takes the distorted-looking geographic image, and wraps it to the circular earth perfectly, because it places ground terrain and mesh geographically.. not by measurement.Without any software to perform the reprojection to geographic, resample will not place the image correctly, as the image needs to be twisted, stretched, bent, etc...There is no inexpensive solution. Software to reproject can cost $100s to $1000s.I know this is bad news, but it is the truth. Small areas ( 1km or so ) can be placed with the distortion mostly unnoticed, but areas of several kilometers will never line up without reprojection.This problem also affects Ground2K. It uses images for background maps that should be in geographic projection.Airport for Windows and FSSC use background images that are orthographic ( measurement based ) in nature, but many aerial images are in UTM format that still will require reprojection to get rid of the twists and bends common to that format.======================I use Global Mapper for my map/image reprojection... costs about $180 US. Justin Tyme has highly recommended Manifold ( about $245 US ). Here's a link to an online Manifold manual that describes the projection problem you are having:http://exchange.manifold.net/manifold/manu...erraserver_.htmDick

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Easy to get rid of the building, use an "exclude file". Search on the term here in this forum, you'll find volumes telling you how to do it several ways.The lining up is explained by Dick, the projection is wrong. As far as nailing your image to the airport, I find best results (once I rotate the image for the projection difference), by using the coordinates of the ends of the runways for the reference points of the project. I think terrabuilder allows two point calibration of the image, just find the coordinates in flight sim for the runway ends, and use them as calibration points. While I can't swear terrabuilder will work perfectly this way, it should.

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Hi Edwin:Dick wrote: "Without any software to perform the reprojection to geographic, resample will not place the image correctly, as the image needs to be twisted, stretched, bent, etc...There is no inexpensive solution. Software to reproject can cost $100s to $1000s."I believe I have found a work-around for reprojections with freeware software. I haven't extensively tested my, admittedly convoluted, procedure because I own payware GIS software myself but you might want to give it a try. The 'guide' is in this thread:http://forums.avsim.net/dcboard.php?az=sho...ing_type=searchRegarding the note at the end: I believe that the way MicroDEM shows the image on-screen is correct. I loaded the .jpg saved from MicroDEM back into MapMaker and the E-W distortion was gone. It seems that this is just an issue whether pixels are diplayed as squares or as rectangles and has no implication on the conversion to the FS format.The final steps, then, are to load the .jpg into your image software, re-save it as .bmp, and prepare the .inf file. However, most likely you'll now have black borders along parts of your image, so you'll have to cut these off. To get the new NW corner, use the CellXdimensionDeg/CellYdimensionDeg values, which give you the extent (in decimal degrees) of each column and row you have to clip (I have set up an Excel spreadsheet to help with this task).Hope this helps. Cheers, Holger

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I'll give it a go and see what I can conjur up. I'm sure I'll have some questions at some point (I'm a complete noob at this stuff).I'm not interested in spending money on GIS software at this point - I'm trying to get this project done before my 60-day eval of Paint Shop Pro ends ;)Cheers,

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That all makes sense now. I can see how rotating the image was only getting me part of the way there.I'm not ready to spend any money on this project yet; so I may have to live with an "almost lined up" result.I am wondering if Larry Jone's OrthoStitch.exe does the reprojection. I can't tell from the manual, which probably means it doesn't do any more than the USAPhotMaps.exe program I've been using.Regards,

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I tried using TerraBuilder's calibration feature using two VOR's 3 miles apart of; but things still were not lined up quite right. I was able to calculate how much to move the image by using LandCalc to figure out the coords of a VOR on the field. After I did that, the airport in FS lines up almost perfectly with the image. But all this is based on a non-reprojected ortho image.I'm going to try Holgers "reprojection with freeware tools" technology and try again.Cheers,

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