Hei

I draw boarders for my maps in Google Earth (sorry Matt, but the backgroundmaps in RM is way off in my part of the world.) I draw the shoreline and islands, and the import them to Reefmaster. This is a great feature, and makes for some brilliant looking maps.

The shoreline excludes everyting outside of it as land when I create a file for my Lowrrance HDS, but how do I get the islands to do the same?




The pic above is a screenshot from my HDS Gen 2. Land is filled in, but the little island is only outlined (in blue) and is not filled.

Another thing that would be great, is if it was possible to name the islands. I know I can get around this by putting a WP in the midle of each island and name the WP, but if it could be done in RM that would have looked even better on the map.

Hi,
Yep - the OpenStreetMap maps aren't as good as Google Earth or Bing, and it is more noticeable in some areas unfortunately. We are always looking at increasing the background map options, but the problem is licensing, not the implementation (I can switch on GE background maps by un-commenting a single line of code, but we can't release it - it's frustrating!). If you do have any map source suggestions that we may be able to use, please post them up. In the meantime, we do always suggest tracing shorelines in GE and importing them to RM as KML files. Another thing you can do is calibrate a satellite image in GE and save that as an image overlay in a KML/KMZ file. You can then import this into RM, which will tile the image on import, and use this as a background to your maps (put the image in the backgrounds part of the overlays list). Yet another possibility that we are looking at is the ability to point RM to a directory containing cached image tiles (stored in the OSM directory structure). This would allow RM to use map tiles from any source, so long as you could "acquire" them and store them locally. It would also remove the dependence on having an active internet connection to view the background maps.

The issue with the islands is actually a problem with the way some later Lowrance units render LCM maps. The type is correct in the LCM file (a water body), and in theory a closed polygon that defines a water body should be shown as a filled island when it is entirely enclosed within another water body polygon. Older units display this as it should be, later units tend not to. There are workarounds that other products use, that involve creating the entire lake (including islands) as a single polygon, with the shoreline cutting across the water to join the island. This gives its own (aesthetic) problem of having a "shoreline" crossing the water. We haven't implemented this in RM, but might consider it - although there may be other options soon also.

cheers,
Matt

Hi,

What Matt writes is probably the cause for your blue island. To rule out any issues in your data/map you can try the LCM in one of the emulators for older units at www.lowrance.com/sv-SE/Support/Product-Emulators/ For example the LMS-527-emulator.

If it looks OK there, then it is related to the bug in the HDS-firmware. A bug they will probably never fix, at least it has been there for years.

Regards,

/Martin

Thanks guys. Not much help, but at least informative. :D
I have a Lowrance Globalmap 5300 as well, I'll try the lcm in that to see if the islands are filled in correctly. I'll also check my HDS Gen 1, but as you say it probably will be the same. But why are the islands on my Navionicsmap filled in? I belive those are lcm as well?

One option could be to simply draw tracks within the island i GE so it's filled in with tracks.

The current backgroundmaps in RM is quite ok as background, and the import of kmz from GE is flawless, so it's my view that there is no need to have GE in RM. (Speeding the software up is a much more important upgrade, as it really slows down when working on big maps. I'm currently mapping a 20 square km lake, and I get to drink a lot of coffe while waiting for RM. The laptop I use is not the fastest of the lot though, so it might have something to do with the speed.)

20km is a big map for ReefMaster. You have to consider that RM grids all the data in a 1m resolution grid, triangulates and interpolates depth values - and only then does it down-sample for the 3D view. So - a 20km grid is 400M data points. Although we don't put an upper limit on the map size, anything over about 10km square is going to take a long time to generate. Unless you have contiguous data throughout the whole lake, I would recommend splitting the map into sections. You can always recombine contours within a user map for export as a single map to your Lowrance, and you won't have to spend so long generating the map each time something changes.
We do have some ideas for some speed-ups as well, which we will probably include in one of the next releases; having an option for a lower grid resolution would be a simple option, at the expense of some contour resolution (although contours from a 2m grid are still pretty good).

cheers,
Matt

I think Navionics and other commercial map cards are using the AT5 format - which is probably the reason that LCM format has been neglected by Lowrance in recent times.

About mapsize and performance. My largest project is about 15x13km with millions of points and 100+ islands. While it takes a while to calculate the complete map I think this is something that must be expected with that amount of area/data. Compared with other products RM isn't slower for me.

Use a larger grid size while just experimenting and when ready to export to final map just change to smaller grid again.

I find having many large user maps stored is something that slows down loading and general performance. Delete the old versions of the maps not needed anymore and see if it help.

/Martin

I know I'm pushing it a bit, so no critizism from me there. More like wishful thinking :) I to have used other SW for mapping, and for it's intended use RM is great, and has reasonable speed.

I have two chips from Navionics from their Gold-series. One is an older 25XG and has nv2-files, and one is a brand new 49XG and has nv2 and ugc-files. I know from experience that Insight Genesis makes at5-files.

btw: another wish is to adjust the flow protection on this forum, correcting typos etc means having to wait 120 seconds. ;)