How to… Create a basic transparent ‘Map’ img

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NeilP
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Joined: Thu Jul 25, 2024 8:20 am

Re: How to… Create a basic transparent ‘Map’ img

Unread post by NeilP »

Yea, I fly air ambulance so it is a 24 hour job. First day back today.
The Marine charts I have seen only deal with the more major areas, no the small gutters right up to the land edge.

My experience and limited knowledge of them has lead me to believe though, that many are merely data converted from much much older analogue charts/ depths done manually the old fashioned way.

I will go and see a mates boat this evening if I have time, and check out his Garmin Plotter, but pretty sure they just bring up copies of paper charts…
NeilP
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Re: How to… Create a basic transparent ‘Map’ img

Unread post by NeilP »

Just looked at Garmin site.

A bit pricey too for my needs !

£320
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Przekątny
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Re: How to… Create a basic transparent ‘Map’ img

Unread post by Przekątny »

NeilP wrote: Sat Aug 31, 2024 3:51 pm Just looked at Garmin site.

A bit pricey too for my needs !
The map is probably not the only expense, tourist devices display maps in the structure of sea maps,
but do not implement all the available options.
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GPSrChive
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Re: How to… Create a basic transparent ‘Map’ img

Unread post by GPSrChive »

NeilP wrote: Sat Aug 31, 2024 3:51 pm Just looked at Garmin site.
A bit pricey too for my needs !
Do the JPEG files you can access include the information you desire? If yes, another option is to convert them into Garmin Custom Maps (KMZ).
NeilP
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Joined: Thu Jul 25, 2024 8:20 am

Re: How to… Create a basic transparent ‘Map’ img

Unread post by NeilP »

Just playing with them now. I created a tiled image from screen grabs this afternoon.

I do see now that another way may just to create tracks in Google Earth Pro and export to kHz then convert to map ..or similar..just drawing the lines on Google Earth maybe an easier way.

The original of this is now 13,000 pixels wide. but all might have been in vain now I have been playing with Google Earth App

I had captured loads of screen grabs of the LiDAR scans fo thsiisland on our local givernment website and stitched them together.
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Lidar Tiles 1200.jpg
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NeilP
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Re: How to… Create a basic transparent ‘Map’ img

Unread post by NeilP »

This is really cool !

i was already playing with the Image Overlay when you mentioned it..but merely as a way to draw the tracks..then I read the Garmin Custom map article....my walked tracks have come out really well over the top of the LiDAR.


see screen grab of the exported image as kHz, vimported in to basecamp.

ignore the picnic table icons! I was just marking "junctions" with what ever Icon happened to come up as last used.


To get the Lidar screen grab image to fit more accurately, I'd need to first screen grab the Google Earth pro area image..and then put that in photoshop and skew/ distorted the Lidar Image to fit. The image overlay tool pin Google earth only allows for size and rotation..it is not possible to get the whole thing stretched in all direction and rotated to fit all points..seems some distortion needed which can be done with Photoshop

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NeilP
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Re: How to… Create a basic transparent ‘Map’ img

Unread post by NeilP »

Thanks to you guys I have got a successful outcome to what i needed.

the LIDAR images were just not suitable to easily view on the litttle Oregon 300 screen, so I created a JPEG overlay using Photoshop and the basic brush tool.. Bright colours to easily see on the screen whilst in the kayak.

Took a screen shot from Google Earth Pro app and put that in Photoshop asa layer.

Created a blank layer over the top and used the brush tool to create basic tracks of safe to fish/trawl a lure, avoiding the oyster farm beds, big rocks etc.

saved as a 1024 pixel JPEG at 156 bit and took back to Google Earth app to export as kmx files..all works just fine.

Only one question.

I have some OSM img maps on the device too, but cant find a way to change the DRAW order number of them.
I ahve my map as Draw Order Zero and some parts of the OSM maps from BBBike to draw over the top..but not all.

Cant seem to find a way to change the Draw order of these maps.

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SECorner MyMap.kmz.zip
Screenshot 2024-09-02 at 13.30.47.jpg
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Przekątny
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Re: How to… Create a basic transparent ‘Map’ img

Unread post by Przekątny »

NeilP wrote: Mon Sep 02, 2024 12:34 pm Only one question.

I have some OSM img maps on the device too, but cant find a way to change the DRAW order number of them.
I ahve my map as Draw Order Zero and some parts of the OSM maps from BBBike to draw over the top..but not all.

Cant seem to find a way to change the Draw order of these maps.
There is no way for a vector map to be above a kmz map.

In the kmz file, you can set the Draw Order above 50, which will make the raster map partially transparent.

To change the display priority of vector maps, you need to change the TRE parameter in the .img file.
Przekątny
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Re: How to… Create a basic transparent ‘Map’ img

Unread post by Przekątny »

Przekątny wrote: Mon Sep 02, 2024 1:02 pm In the kmz file, you can set the Draw Order above 50, which will make the raster map partially transparent.
I've checked now: in Base Camp > Properties > slider down - more transparency.
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NeilP
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Re: How to… Create a basic transparent ‘Map’ img

Unread post by NeilP »

Przekątny wrote: Mon Sep 02, 2024 1:02 pm
In the kmz file, you can set the Draw Order above 50, which will make the raster map partially transparent.


For me the only way to get visibility of the gmapsupp img map is the reverse of that...to have the kmz file map set with DRAW order BELOW 50. if it is 50 or above then the main map is hidden.

See screnngrabs.
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Below 50
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Above 50
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Przekątny wrote: Mon Sep 02, 2024 1:02 pm To change the display priority of vector maps, you need to change the TRE parameter in the .img file.

I'll search again how to do that tomorrow...I had a brief look just now and got no hits for the field and img maps yet.
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