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PostPosted: 20 Aug 2016 07:30 

Joined: 28 Mar 2011 03:35
Posts: 75
Without veering too far off (my own!) topic, I might have mentioned previously that the historic 1:50,000 Italian maps from Castaneda have the latitude and longitude based from Rome!

Anyhow I will delay doing anything with the Yugoslavian maps pending your research Roland, main thing is I have them securely saved and backed up for future reference.

PostPosted: 21 Aug 2016 08:07 

Joined: 30 Jan 2011 13:03
Posts: 161
G'day geophil,

Are you back home from Italy, yet? If you are, Roland, I have a problem elsewhere that I need to discuss with you. If so, I will create a new thread for it in a more appropriate place...

...with regard to that series you mentioned, would that be "The Map Makers", Narrated by Stephen Rashbrooks?. If so, it is available on DVD, so you ought to be able to track down a copy for yourself. As well as that, there is another series, that I can recommend called "Mapping the world", which is presented by Professor Jerry Brotton and equally worthy of having in one's collection. There is also the excellent series of programs presented by Terry Jones (yes, the same Terry Jones of Monty Python fame - the Welsh one), in which he concentrates on the development of Medieval maps in England (not quite in the same vein but still very well done), entitled "Terry Jones' Great Map Mystery") but I can't find it in EZDVD to a provide a link for you...

...I'll catch up with you elsewhere (and give BigVern his thread back)...

Jerker {:)}

PostPosted: 22 Aug 2016 10:47 

Joined: 05 Jan 2011 16:45
Posts: 1119
Garry, I looked it up. The BBC miniseries I was referring to is called "Maps: Power, Plunder and Possession", and tells us about a number of political aspects in addition to the history of map making. I found a brief description here: ... Possession

Back to Yugoslavia:

The "Greek Datum" turns out to be a problem. The simplistic transformation I found that just adds a few arc seconds to the more recent GGRS87 datum might work for areas near the origin in Athens (which I haven't tested) but is pretty useless for Yugoslavia. I tried a map sheet for the Danube, near the Hungarian border, and the error was about 500m!

What did succeed, however, was a test for the Lambert projection. I tried the "Red" grid (the "Danube" zone as defined by the War Office). And the red Lambert grid matched the geographic coordinates (blue longitudes, Greenwich prime meridian) quite well.

But without a proper transformation into the WGS84 world, no DEM will fit.

What I can try is to compute a custom Helmert transformation. It needs a series of matching coordinate pairs, their world vs. our world, scattered across that entire region. These coordinate pairs would then be fed into some external geodesy software that solves the linear equations and delivers the 7 Helmert parameters (3 x translation, 3 x rotation, 1 x scale), applying regression and minimum mean squared error.

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