Lat/Lon2Fly!Coords and Fly!Coords2Lat/Long

[Guest]

Hi everybody, I'm trying to make some photoreal scenery from orthophotos but the fly editor text-info files require that the coords be in Latitude/Lontigude format. On the other hand the geo-referenced files accompanying the photos contain a different coordinate system. I found a file ("flycopm.zip")in the Av-Sim library to make the conversion (although I'm not sure it would convert to the orthoimages format) but it wouldn't start, asking for a missing .dll. Although I managed to dig this .dll up from my VB6 libraries and copyed it into the windows system dir the program still wouldn't start stating 'class no registered 'etc. All in All I couldn't use this utility. So, could somebody please give me a formula to convert Lat/Lng Coords to the orthoimages coordinates Format and vice - versa or suggest an on-line WORKABLE utility to do this? One more thing.. Are those coordinates (I mean, found in .tfw or .hdr or .jgw files)the same used internally by airport/runway fly's databases? Thanks in advance, manolis

[Guest Colins2]

Hi Manolis,I doubt very much that the photos are in Fly! coordinates, even though they may resemble them.Fly! coordinates are really simple as they are basically geographical seconds.Longitude is measured 0, esatwards to 360 deg in secondstherefore 359.59.59 E = 0.0.1 W = ((359*3600)+(59*60)+59)=1295999"Lattitude is also in seconds, measured equator to pole starting at the equator. +values northwards and - values southward.Your orthophotos are probably in UTM coordinates (Universal Transverse Mercator) You should be able to find a utility to translate this for you.UTM coordinates are measured in metres. They work on 6 deg wide 'slices' of longitude called zones. The world is split into 60 zones starting at the 180 deg meridian and going eastwards round the world.Hopefully the data you have will tell you the zone and the spheroid on which the photo coordinates are based.Hope this helpsColin

[Guest]

Thank you very much Colin for the Fly-Coords conversion formula.It'll be very usefull to me as I want to add some airports to the databases. Meanwhile, yes I found some online utilities to convert between UTM <-> D/M/S yet I'm still a bit confused cause like you said it seems that more than the "Easting" , "Northing" and image resolution settings contained in the description files is required for the conversion: grid zones etc. Thanks again, manolis