Blurred Custom Map Tiles

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ianchapp
Posts: 19
Joined: Tue Feb 18, 2020 6:17 pm
Has liked: 6 times
Great Britain

Blurred Custom Map Tiles

Post by ianchapp »

I've made a few custom raster maps, where each KMZ consists of 16 1000x1000px jpg tiles.

The majority of tiles appear a bit blurred (not unusable). But some are pin sharp, even within the same KMZ.

The KMZ (including tiles) have been automatically generated, from a digital original, using MAPC2MAPC, so the jpg settings etc are consistent. I've tried turning 3D terrain off. I can't detect any difference in Google Earth.

Any idea why this is happening please?
ianchapp
Posts: 19
Joined: Tue Feb 18, 2020 6:17 pm
Has liked: 6 times
Great Britain

Re: Blurred Custom Map Tiles

Post by ianchapp »

OK, I've solved it, after a LOT of trial and error, including changing every possible setting in MAPC2MAPC.

The issue is to do with image size. My images were 1000x1000px, which according to Garmin are OK, they specify a 1 megapixel limit. Which I think means 1024x1024px. But 1000x1000px cannot be relied upon, typically I would only get full res. from one tile in every sixteen.

If I split a 4000x4000px tile into 20, or even 18 (despite the horrible maths), it will work fine. But 16 tiles cannot be relied upon. Obviously we need the tiles to be as big as possible, as I think the XT will only accept a maximum of 400.

Hope that helps someone, and saves them wasting a day of their lives....!
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