Thanks for the suggestion. In this case, I try to assign both an English and Japanese address to an object (restaurant) in Japan. In Japan, addresses are not based on street name and house number. Addresses are based on areas which are divided into blocks, which are subdivided into smaller blocks and then divided into even smaller blocks. So the address refers to a block of land rather than a street with house number. For example, Shibuya 1-14-15. http://maps.google.com/maps?q=Japan,+T%C5%8Dky%C5%8D-to,+Shibuya-ku,+Shibuya,+%EF%BC%91%E4%B8%81%E7%9B%AE%EF%BC%91%EF%BC%94%E2%88%92%EF%BC%91%EF%BC%95&hl=en&ie=UTF8&ll=35.660121,139.702599&spn=0.011768,0.022724&sll=35.664257,139.701223&sspn=0.023535,0.045447&vpsrc=0&geocode=FVohIAIdQ7FTCA&hnear=Japan,+T%C5%8Dky%C5%8D-to,+Shibuya-ku,+Shibuya,+%EF%BC%91%E4%B8%81%E7%9B%AE%EF%BC%91%EF%BC%94%E2%88%92%EF%BC%91%EF%BC%95&t=m&z=16

Thanks for all the comments. bri g mentioned that it is possible to offset the map in JOSM. Is something similar possible in Potlatch 2?

Does local authorities maintain points with an accurate lat/lon and if so does anyone have experience with using such a point to adjust the offset?

Then again, the French were off significantly when determining the equator, but that was a more than a hundred years ago :-)

So assuming the satellite image is located correctly and making changes to OSM was a mistake?

I took four GPS readings with two different GPS' gave me four different readings.

How do I know the correct position to adjust the imagery?