"New" digital charts on GoogleEarth

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A flyer for this dropped thro my letter box today. Any one tried it or got any comments?

It looks quite usefull & seems to use SeaClear charts with GoogleEarth core software. It can be used on-line at home for passage planning, or the relevant charts can be saved on your PC with a GPS dongle for use as a chart plotter when out of interwebby access.

So can anyone see the snags? I hereby challenge the forum to shoot this one down, before I actually dig in & spend some money :eek: Nah, don't worry, that almost certainly won't happen err, I hope. :rolleyes:
 
A flyer for this dropped thro my letter box today. Any one tried it or got any comments?

It looks quite usefull & seems to use SeaClear charts with GoogleEarth core software. It can be used on-line at home for passage planning, or the relevant charts can be saved on your PC with a GPS dongle for use as a chart plotter when out of interwebby access.

So can anyone see the snags? I hereby challenge the forum to shoot this one down, before I actually dig in & spend some money :eek: Nah, don't worry, that almost certainly won't happen err, I hope. :rolleyes:

Well, there are issues with GE's map projections - they aren't the usual Mercator, and don't have (quite) the properties you expect. But I doubt it'll make much difference in coastal waters. But for a long passage, a straight line on GE ISN'T a rhumb line.

There also appear to be issues with the tiling of the charts; there is (for example) a distinct discontinuity at the north end of Arran on the demo version. This may be to do with the different map projections used by charts and by GE, resulting in less than accurate rendering of the chart.

It is not clear whether the charts supplied are raster or vector. If raster, then be aware that you won't be able to remove detail (often useful on small screens) and that zooming in or out can have strange results.

However, it looks a useful tool, but no more so that other things such as Memory Map (which has useful route planning functionality). I'd say it is overpriced considering the relatively limited functionality of GE.
 
From the flyer;

They are described as "Quilted Raster chart layers, which behave like Vector charts" with autoloading of best scale chart (presumably with the relevant level of detail).

It also includes 1400 pdf pages of Pilotage info -which is something most packages don't have. But please keep knocking them, I am in serious danger of spending here!
 
I;ve been beta testing the product and haven't found much wrong with it

There are two seperate setups on the DVD - chart overlays for Google Earth and a reasonable set of smaller scale raster charts for use with an included copy of Seaclear II

The latter charts are encrypted and cannot be loaded without the DVD in the drive

On the beta test version there were some tiling problems with the Google Earth overlays often requiring zooming in or out one level to overcome (not a major issue) - this may have been sorted on the production version.

The accuracy of the tiling is reasonable and good enough for the purpose although, as AntarcticPilot rightly pointed out there are going to be discrepancies due to differences in projection - GE uses what it euphemistically calls "Simple Cylindrical Projection", the Admiralty charts are either Mercator or Transverse Mercator with the very occasional Gnomic projection chart still kicking around. Therefore, the charts will not overlay absolutely 100% perfectly (and indeed a larger scale Admiralty Transverse Mercator chart will not overlay directly on a smaller scale Admiralty Mercator chart)

The charts are raster Admiralty SNC's by the way, latest 2010 edition. They are not updated to the latest NM's and there is no mechanism for doing so. However, this is not a product intended as a primary means of navigation so I don't see that as a major issue

It's a great planning / dreaming about that Round Britain trip I'll probably never do / getting an eyeball view of a scene in relation to the chart tool and I'll be buying a production version as soon as I get paid this month (spent too much on the boat already!)
 
If this had been around last year when I was buying charts etc I am sure it would have been one of my backup systems, at that price one would have been foolish not to
 
Thanks, guys. ( I love this forum!!!)

So the 260+ SeaClear charts "suitable for use on passage" are just smaller scale stuff, that can be used with pre-saved GE/Visichart detail charts of the harbours?

I was interested to see that you can add an AIS input too. I have heard good reports of SeaClear in the past, am I right in remembering that you can scan your own charts in & stitch them into existng ones?
 
So do you have to be able to access GE in real-time to use these charts? Not an option where I sail.

No. You use the full detail VisiCharts with GoogleEarth zoom/ 3D view tools etc & can overlay the satellite pictures with the charts while at home to plan the trip. You save the detail charts you want (don't forget plans B & C) on your PC. Then, at the boat, without access to the interwebby, you use the SeaClear charts & overlay the detail ones you have saved. Just add a GPS dongle for a plotter capability.

At least, that's what I reckon from the literature & the input from a user on this thread.

I currently use Tsunamis, but the interface is pretty poor & it can be hard to remember how the get what you want in a wibbly wobbly cabin at sea.
 
Thanks, guys. ( I love this forum!!!)

So the 260+ SeaClear charts "suitable for use on passage" are just smaller scale stuff, that can be used with pre-saved GE/Visichart detail charts of the harbours?

I was interested to see that you can add an AIS input too. I have heard good reports of SeaClear in the past, am I right in remembering that you can scan your own charts in & stitch them into existng ones?

The Seaclear charts go down to quite a reasonable scale but lack the ultimate detailed charts - for example, the River Crouch / Roach chart is not included (dammit!) but the Thames Estuary (approach charts) etc. are so there's what you need for passage planning but not the detail for the initial or final bit of creek crawling / harbour entry for which, as you rightly surmise, you could use the GE overlays although without the chart plotter facilities of Seaclear

Yep, your recollection is correct. You can load your own raster chart images* into Seaclear using the provided MapCal utility to georeference them. You can't stitch charts together in Seaclear (although you could do so in a graphics package and then load the resulting image into Seaclear) - Seaclear doesn't do stitching, it loads each chart or chartlet as a stand alone image file and when you get to the edge of that chart it loads the next adjacent chart at the largest scale available

I haven't tried it but Seaclear does support an AIS input too. One day, when I can afford an AIS engine, I'll have some fun with that!

The challenge of course is a source of UK charts for use with Seaclear - the VisiChart package at last makes UK raster charts available at a price I can afford / am willing to pay - I've suggested to the guys behind the package that an additional DVD of detailed harbour scale charts would be something I would also purchase at a similar price but they haven't got back to me on that idea yet!

The biggest drawback to the setup as a serious passage planning / navigation tool (as opposed to something to play with) is the inability to apply NM's to the charts. The full charts for Seaclear and the tiles for GE are encrypted (and the UKHO tested the encryption pretty thoroughly before licencing the product apparently) and cannot be modified and Seaclear has no mechanism for adding symbols or inserting chart corrections (it's biggest drawback whether included with VisiCharts or as a package in its own right)

With that caveat in mind, I still think it's worth the money being asked - and no, I'm not on commission :)
 
Thanks, guys. ( I love this forum!!!)

So the 260+ SeaClear charts "suitable for use on passage" are just smaller scale stuff, that can be used with pre-saved GE/Visichart detail charts of the harbours?

I was interested to see that you can add an AIS input too. I have heard good reports of SeaClear in the past, am I right in remembering that you can scan your own charts in & stitch them into existng ones?

Seaclear 2 is free. Google Earth is free. The grid overlays etc are free, you just have to download them. I don't have the link at the moment its on my other machine but if you go to the Seaclear forum all this info is available for free. Someone has merely done some basic work with a free product and selling it on, quite common on eBay with Seaclear.
 
Seaclear 2 is free. Google Earth is free. The grid overlays etc are free, you just have to download them. I don't have the link at the moment its on my other machine but if you go to the Seaclear forum all this info is available for free. Someone has merely done some basic work with a free product and selling it on, quite common on eBay with Seaclear.

The 260 UKHMO charts are not available free tho are they? & the VisiChart/GE overlay capability is quite nice too. They are the main benefits for most people, the other stuff has just been tweaked to work better as you say. I am not convinced by your comment.
 
Look at OpenCPN which is free and does raster or vector charts (Seaclear only does raster). I have both and OpenCPN is way better in my book and it also does AIS. It is still possible to download a 2010 full worldwide set of CM93/2 vector charts with a little Google searching free, but the later C-Map CM93/3 are encrypted and not useable. I have Tsunamis also with worldwide charts (but rather older, 2000 I think) and find it the most user unfriendly program ever.
 
Seaclear 2 is free. Google Earth is free. The grid overlays etc are free, you just have to download them. I don't have the link at the moment its on my other machine but if you go to the Seaclear forum all this info is available for free. Someone has merely done some basic work with a free product and selling it on, quite common on eBay with Seaclear.

totally wrong in fact

Yes, GE and Seaclear are free

What is not free and is not readily (or legally) available are Admiralty Standard Nautical Charts as GE overlays and Seaclear compatible charts. It is the charts that VisiChart are charging for, not GE or Seaclear

From conversations (by email) with the developers I'm aware of just how much effort it has taken to make the SNC's available on-line, as GE overlays (both on-line and on DVD) and as Seaclear calibrated charts (DVD only)

The developers have had to satisfy the UKHO as to the encryption and security of their products - the UKHO is paranoid about their intellectual property being pirated. They have also had to negotiate with hundreds of information providers. Look in the source box of any SNC and you'll likely find several sources such as harbour authorities, local authorities, foreign hydrographic officers etc. and VisiChart have had to obtain permission from every single one of them before a chart can be made available (which is why the French data is blanked out on the channel area charts - the French authorities have refused permission for their data to be included via SNC's on the VisiChart product)

Then every single chart has had to be divided into tiles and georeferenced to create the KML file for GE plus each chart has had to be calibrated for Seaclear. There's a lot of work there, it may not be that complex but it takes a lot of time and time is money

My only connection with Visichart is as an early subscriber to the web based service and a beta tester of the Visichart DVD (which came about because I flagged up some minor glitches in the web based charts and was then asked if I would be a beta tester)

Personally, I think having access to very nearly the entire UK set of SNC's for rather less than the price of a single leisure chart folio is a bit of a bargain!
 
There also appear to be issues with the tiling of the charts; there is (for example) a distinct discontinuity at the north end of Arran on the demo version. This may be to do with the different map projections used by charts and by GE, resulting in less than accurate rendering of the chart.

I see a rather more fundamental "bug"

As you zoom in, you see each "tile" load, but then when the tile next door loads, the first one gets 90% covered with white. So you end up with a mostly white screen, with just thin bits of chart showing.

Is that a problem with my computer, or just a bug in the software?
 
I see a rather more fundamental "bug"

As you zoom in, you see each "tile" load, but then when the tile next door loads, the first one gets 90% covered with white. So you end up with a mostly white screen, with just thin bits of chart showing.

Is that a problem with my computer, or just a bug in the software?

+1 it is way too clunky for me and I have high speed broadband and a high spec PC, unless this gets better I won't be renewing my sub. I also subscribe to the wreck database which has UKHO charts for most of the areas I am interested in.
 
VisiCharts pros and cons

Vested interest here, we "invented" them, they are a spin off from our web work. This is the page that deals with them:

http://www.visitmyharbour.com/visichart-dvd.asp

Unlike many sales pages this will also tell you clearly what not to expect, and you can speak to the designer directly.

The only person on this page who has actually tried VisiCharts on DVD is Brigantia, any other comments are related to free online demos.

VisiCharts on DVD are nothing to do with membership...these you buy and keep, the don't expire and they are licensed for nav. The problem we've had is GE and Seaclear are free (good) programs, we can't interfere with them in any way. We've developed CONTENT for them and encrypted it to satisfy UKHO. This means they are locked to the DVD, rather than your computer. Portability is a plus, clunkiness is a minus.

All 800+ UK charts are in VisiChart format for use in GE, you select the charts you want, they overlay onto GE and mix themselves together. Multiple charts of differing scales can be loaded, GE shows the best chart/s for depth of view.

GE does not use mercator projection as it is in itself a 3D globe (mercator is a method of showing a 3D image in 2D). For the most part chart and satellite image lock together very well, right down to pontoon level.

It is possible to use VisiCharts in GE offline, they are independent of the satellite images, you can even pre-cache 2GB of GE imagery for offline use too. Connect a Garmin or Magellan GPS and you'll have position on the chart/image. Load routes/waypoints from these too.

Google Earth is NOT a chart plotter however, although it does have some useful functions that could be used...line, placemark, route. We've see US charts in Google MAPS, but UK VisiCharts are in Google EARTH which gives 3D rolling road capability, offline use, GPS input etc.

Tiled charts, satellite images, etc are heavy on the computer, so don't expect lightning speed, but do expect them to be perfectly useable.

For real-time use at SEA we also put SeaClear on the disc, pre-loaded with all charts of 25,000:1 and up..this is for at sea use, and MUCH FASTER than GE. Simple, tried and tested plotter, now at last with UK charts.

This is pretty new stuff, maybe not to everyones taste. However initially priced at under £50, (with exchange fresh charts discs yearly, heavy discount) this could be worth a good look. Only for Windows.

VMH offer 30 day money back guarantee if disatisfied in any way, so you could try at home with no real risk.

Hope this does not all sound too much like an advert, we really are quite proud of this...
 
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I see the worldwide CM93 charts come in 10 parts. To save me downloading the lot, which part covers the UK?

thanks.

I didn't know they were in sections and when I got mine I downloaded the whole lot in a 1Gb zipped file. You need a (free) torrent stream program like Bit Torrent to download them, still takes an hour or two, and another (free) program like IZArk to unzip them because Winzip doesn't.

BTW It is easier to reference charts to OpenCPN than Seaclear11 because you simply point it to the folder containing all the unzipped charts, whereas with Seaclear you have to point to each chart individually.
 
I didn't know they were in sections and when I got mine I downloaded the whole lot in a 1Gb zipped file. You need a (free) torrent stream program like Bit Torrent to download them, still takes an hour or two, and another (free) program like IZArk to unzip them because Winzip doesn't.

I googled, and it took me here [removed by admin] no doubt there are many other places as well.

On that page, the 2010 CM93 charts can be downloaded in 10, 100MB chunks.

Since I am on a sloooooow broadband connection with a usage cap, I would rather only download the batch that contains the UK charts. Anyone know which that is?
 
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Overner, thanks for your input, very helpful.

I was interested to see your competitor comparison on the site. Did you do any comparison with Fugawi global navigator? I have some of their OS maps software & was impresssed with what that did.
 
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