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Thread: Interesting blog post about georeferencing old maps.

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    Administrator Redrobes's Avatar
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    Default Interesting blog post about georeferencing old maps.

    Posted on tech news today I found this one:

    https://www.davidrumsey.com/blog/art...interpret-maps

    interesting and diverted me for a while looking at all of these nice historical and hand drawn maps georeferenced into modern coordinates and projected onto globes. Very nice bit of work and I think he is demonstrating his georeferencer but in any case he did a good job of it.

    Where he has projected some of these onto globes he might have found that using a high pass spatial filter to remove the offset of local DC brightness or the grid effects of the tiles useful and would have produced a better result in some of the cases. Then he would have had a smoother transition between the tiles. Perhaps for this post it fixes the problem enough so that people wont be able to see the tiles any more. I might download one or two and show what I mean.

    But have a look at the post when you have half an hour free because its quite the rabbit hole.

    Edit: Did a grid remove of a section of the french map as an example. And another of a bit of the Germany map where the grid is very distracting.
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    Last edited by Redrobes; 01-27-2022 at 07:20 AM.

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