Thanks to both Rossko and Andrew Leach for their input, interesting to note that there are in fact significant errors in the Google map data. This, combined with an even bigger error source I just found, explains the errors I see - when looking at Bornholm in ArcMap, the band of weaker TV signals seemed to be inland,but this was due to a misconfiguration of the ArcMap GUI - I saw the coastline of the overview vector data overlapped with the coastline of detail vector data. When removing the overview vector data, the weaker band of pixels is in fact just outside the beach, as it is in the tiled overlay in Google maps...! The "overview vector data" beach is approx 600m west of the "detail vector data" beach, so in fact my conversions, tiling etc seem to work correctly.
/Erik Alapää On 13 Aug, 20:37, Rossko <[email protected]> wrote: > In the middle of this satellite view there's a lighthouse, about 100m > inland from the Bornholm > shorehttp://maps.google.co.uk/maps?f=q&source=s_q&hl=en&geocode=&ie=UTF8&t... > 55.298235,14.77391 read off the satellite image. > > Switch to ordinary map, and you won't see any land at all. I estimate > the coast error at around 400m here > > I believe that's Hammerodde light, > http://www.leuchtturmseiten.de/home.htm?5275 > stated to be at at 55°17'53.2''N - 14°46'25.4''E "GPS" - probably > WGS84 then? > converting to > 55.298111N Long: 14.773722E > which I reckon is within 20m of the satellite view > > Conclusion : the 'ordinary' Google maps aren't very good at coasts - > I'm not suprised, they're only road maps really, not accurate charts. > > cheers, Ross K --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google Maps API" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/Google-Maps-API?hl=en -~----------~----~----~----~------~----~------~--~---
