What Exactly Is HD Radar ?

[OrangeCrush]

I am looking at getting a Garmin GMR 18 (along with the Garmin 3206 chartplotter/radar display) and I am wondering what the difference is between the HD units and the non HD units. Obviously the HD stands for High Definition but what exactly does that mean? The price difference seems to be at least $150 bucks and I am wondering if something specific and useful or just a catchy descriptor.

[s/v Jedi]

Before going into details, read this: Panbo: The Marine Electronics Weblog: HD radar, especially Furuno's

With the invention of radar, during WW2, all you would see is a round blip on a round screen (CRT). That was very low definition, just on or off.
There are several ways to increase "resolution" and the best way is to improve the data received by the scanner (antenna). The bigger the scanner the better, because the horizontal angle is smaller; this means that much more (smaller) sections can be scanned.

With digital radars becoming main stream, it became possible to improve the processing of received signals. At some point after introducing DSP's they started calling that HD radar.

Always keep in mind that a bigger scanner is always better and this will make more difference than HD vs non-HD on modern units. But by any means, if you have selected the size scanner that you can accommodate (and stays within budget), select a HD version to further improve the image.

I would strongly suggest you take a very good look at the new Furuno radars on 3D displays. They have some improvements that are not available on other non-commercial radars like true dual-range option and 5 scan speeds. For your boat, I would choose the smallest Furuno radome scanner or, if you sail where fog is abundant, the 4kW radome.
Many sailors have been unhappy with the chart catalog for the 3D series, but you can now order models that support C-Map too, which is what I am gonna do.

Also, read more on the Panbo blog about the subject. This is the best source available.

ciao!
Nick.

[OrangeCrush]

Thanks, Nick.

That article is very helpful indeed. I am aware that Foruno is ahead of the game in general, but I think I have to lean towards the Garmin setup for mostly budget reasons. I can get a plotter at the same time (which I also need) and spend about $1500 on the combo. I don't see any Foruno options in this range.

I really wouldn't be in the market for Radar if I weren't planning a trip up the Maine coast, so yes fog is my main concern. The Garmin GMR 18 and 3206 chartplotter combo still seems to be my best bet, unless people really feel that strongly against it.

Thanks for the answer!

[David M]

I concur with Nick that the Furuno NavNet 3D vector charts are nowhere near the best I have seen. They don't even have one for the Delta area. The colors are bizarre and a lot of information is not there compared to a paper NOAA chart. I use the NOAA raster scan charts instead.

[senormechanico]

I have a Garmin 5208 with 4kw HD radar.
The imagery is much crisper than my old Raytheon LCD unit, or the Vigil RX I had on a previous boat.
In the radar overlay mode, channel piling markers are a bright orange pinpoint overlaid on the chart. It's a good way to confirm what you are expecting if not actually SEEING in the dark or fog.

[s/v Jedi]

Originally Posted by OrangeCrush

Thanks, Nick.

That article is very helpful indeed. I am aware that Foruno is ahead of the game in general, but I think I have to lean towards the Garmin setup for mostly budget reasons. I can get a plotter at the same time (which I also need) and spend about $1500 on the combo. I don't see any Foruno options in this range.

I really wouldn't be in the market for Radar if I weren't planning a trip up the Maine coast, so yes fog is my main concern. The Garmin GMR 18 and 3206 chartplotter combo still seems to be my best bet, unless people really feel that strongly against it.

Thanks for the answer!

For Maine, you really should opt for a 4kW radar like senormechanico described. A quick Google confirms the GMR 18 is 4 kW so you're good to go ;-) I agree that the Furuno options come with the costs in dollars and as you're normal cruising grounds aren't in Maine (where are you?), you probably don't use radar often enough to pay that much more for these features.

David: did you look for updated firmware that supports C-Map yet? I think an update will enable C-Map without the need for new hardware but I am not sure and don't know if it's available already.
The vector charts for the US are the NOAA vector charts and they should not lack any info relevant to navigation that is on their raster charts. If they do, you should report it to NOAA so they can correct that (they outsource the conversion process)

I am currently in shock on the Panbo announcements on the new Furuno GP-33 GPS and RD-33 repeater displays. Wow, what a step from the GP-32 and RD-32 units. These are seriously going to hurt Garmin and Raymarine and may be even Maretron (the one to beat). I am very happy I had postponed buying new kit for a year because I would have been so sick to see all the new stuff just after installing expensive equipment. I think Garmin will react with new versions of their displays but don't think Raymarine will. Question is what B&G is doing....

ciao!
Nick.

[sck5]

i have a garmin 18 HD radar. really a great unit. fantastic definition. There may be better ones out there but you wont be unhappy if you get the garmin.

[OrangeCrush]

Great info, guys, thanks!

[hanschristian38]

Why are there so many complaints about Maine fog. Forget the radar and get a bag of potatoes and save some money.

The Maine Visitors Bureau would like all this negative talk.

[hummingway]

A bag of potatoes? How does that work? Sonar? You throw a potatoe and if someone says ouch you know there's a ship out there?

[hanschristian38]

You put acrew member on the bow with aack of potatoes and have her throw one every minute - if you hear a splash, keep going.

[OrangeCrush]

So... I am finally ready to purchase a unit. Based partially on the advice here, I am leaning towards spending an extra 300 bucks for the vague distinction of having a Garmin GMR HD dome versus the regular Garmin dome (1000 versus 700 bucks). Is there anyone out there who feels this is not worth the price difference? Does the HD have any advantages besides a sharper screen image?

[s/v Jedi]

I wouldn't hesitate a second.... yes, the difference is worth it. If you have the HD version after having non-HD before, you wouldn't want to go back to non-HD even if they would offer more than that $300.- back into your pocket.

ciao!
Nick.

[sck5]

what nick said. once you see it you will be hooked. i first saw it at the annapolis boat show and wasnt disappointed when i put it on my boat. HD forever for me. It is well worth it.

[svaletheia]

Question for you HD fanatics -- is it worth it to sell an older Furuno VX2 system and get the upgrade - e.g. is that cost difference (most likely > $1k) worth the HD difference for a cruising sailor?