Satellite photos

[BigInch]

I first directed this question to the surveying and geometrics forum, but didn't get any comments. I was wondering if there might be more interest on this forum. Mind having a look at this thread concernig distortions of satellite images available on the internet, Google Maps, Terraserver, etc. Thx

thread159-170407

BigInch-born in the trenches.

http://virtualpipeline.spaces.msn.com

 

[looksatstars]

pretty interesting but I havent found it to be that large of a distortion in the ways ive used it.
Maybe its just some areas that have too many or too little sat. photos for the same area.

 

[BigInch]

Thanks Stars. I've been trying to get some comment for a week now as a sanity check.

If you're just interested in point locations, it wouldn't matter too much and might even go unnoticed, but if you're traveling between those points using bearings, you get far off pretty fast. I just happened to notice while lining up the runway on some stitched photos with a point off of the photos on an aviation chart and with what I thought the rest of the world looked like and my angles were 10 degrees off. I've only checked a couple of places in the world and I don't believe this is true for North America, but in Spain the 15m resolution photos are not correct; strangely the 30m are OK. I am writing a batch program to stretch all the photos in my collecton to more accurate average edge distances appropriate for the latitude. It amounts to 5 meters difference between the north and south edges here, but the E-W to N-S edge ratios on these photos are 1:1.25! For me, far too much error to go without correction.



BigInch-born in the trenches.

http://virtualpipeline.spaces.msn.com

 

[BigInch]

make that 0.05 m.


BigInch-born in the trenches.

http://virtualpipeline.spaces.msn.com