Nearmap to MicroStation (Jpg)

Question

Hi, 
 I have a jpg nearmap export in US survey feet with a jgw file. When I attach the file the coordinates are slightly off from the jgw file. I've tried toggling all the settings to see if anything would work but no luck. This is specifically EPSG 2278. What would be causing the shift in the coordinates?

Rod Wing · Answer

Take a look at your User Preference settings under the Raster Manager category. 
 There is a Georeference tab that allows you to set the units of the World File (Sister File), and the units of the raster file. Both of these settings default to Meters. Change them both to US Survey Feet. 
 You will also want to toggle on the checkbox to Use Sister File, but leave the Save Location checkbox unchecked. 
 
 This image is from CONNECT, the V8i version has the same options, just formatted a bit differently.

Lorys · Answer

can you open the jgw file with note pad and post the contents here as a lot of the settings are in this txt file... 
 Have you other similar rasters in us survey ft open the jgw file and compare it with the problem one if same datum and same units then most of the settings will be the same except for the origin xy

Lorys · Answer

From memory Nearmap is not ortho corrected. So the greater the height of objects above ground the greater parallax error or mismatch between ground and heights so your never going to to get perfect alignment relative to real survey ... especially say a freeway ramp over a road or tall building tops will tilt over and actually fall outside their surveyed base or title. But you get what you pay for... 
 Before we had Nearmap you needed to get a flight run for you if there was no library recent stock films, and then you paid a little extra for it to be ortho corrected this was done with overlapping photoruns and clever optics and it helped to reduce the parallax error...I believe this is still available from some agencies and is now done with clever programming and overlapping photos... but might be expensive to pay on top of nearmap.. ask near map if they offer the extra service for a specific site... but how perfect do you need it.. at what scale are you going to print anyway... my stuff is usually never more than 500 mm out, even if I capture it from Google Earth pro ( for free) that's not bad . 
 So now if you have survey you can adjust the position of the photography in your drawing sheet view to make it better you'll never get it perfect for large areas and it also gets worse around the edges ( I think due to the curvature of the earth) .. Well thats my 2 cents worth..

Nearmap to MicroStation (Jpg)

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