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Full Version: [CA11] Axiom/Lighthouse 100-target AIS limit
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Hi--I recently installed an Axiom 7 running LH3.6. It receives AIS data from a Vesper XB-8000 via STNG/NMEA2000 network. My problem is that the MFD only plots AIS targets out to a distance of about 5 miles. I know from accessing the XB-8000 that it is tracking vessels out to 30+ miles. When I first power up the MFD, I can see distant vessels, but then they quickly disappear (within the first minute). The LH3.6 documentation indicates it only tracks the nearest 100 targets. So I guess what is occurring is that there are 100 targets within 5 miles and then the rest are ignored. I cruise in Puget Sound where there are dozens of pleasure boats with AIS, most of them moored or tied to the dock. These "static" targets fill up the 100-target limit preventing me from seeing the fast-moving ships coming down the sound until they are right on top of me.

Is there a workaround? (Even when I activate the "don't show static targets" option, the problem remains; it seems that though the static targets aren't plotted, they still take up one of the precious 100 slots.) Is there a way to only track Class A targets? Or perhaps the next update of LH will expand the number of targets tracked? I this area, it is not uncommon to see almost 200 targets being tracked on the XB-8000.

Welcome to the Raymarine Forum dagelm,

When operating with the latest LightHouse 3 software update (v3.6.32 at the time of this post), the static AIS targets may be hidden within the Chart application (MENU->TARGETS->AIS SETTTINGS->HIDE STATIC TARGETS (<2kts)). Detailed information on this subject may be found within Chapter 8.3 - Target tracking of the LightHouse 3.6 Advanced Operation Instructions. Raymarine has also logged a feature request to not sound the Dangerous Targets alarm in conjunction with static AIS targets.
Hi--Thanks so much for the quick reply! Unfortunately, hiding the stationary targets does not help. Doing this seems to only hide the stationary targets on the chart but they still appear in the AIS Targets list and continue to count toward the 100-target limit. For example, if I look at the AIS target list I see a large number of targets showing 0.0 kn SOG (even though the hide stationary targets option is set to "on". And if I press the "show on chart" button for any of the 0.0 kn SOG vessels, the chart zooms to an empty patch of water (e.g., a slip in my marina) where the boat is tied up but no AIS target is shown on the chart, because it's hidden. I confirmed that I am running LH3 version 3.6.32. Any additional ideas? Thanks again! --Mark

Your comments regarding AIS target tracking have been logged for consideration to be included within a future LightHouse 3 software update.

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Hi—If possible, I’d like to add some additional context and urgency to this earlier request to significantly increase the AIS 100-target limit in future revisions to the software.
1. In popular boating areas like Seattle there are now literally hundreds of recreational and commercial vessels with active AIS transmitters operating. Last weekend, for example, my AIS receiver was tracking 280 vessels out to a range of 35 nm.

2. The current software only allows the closest 100 targets to be tracked and plotted. (Even if the option to not show stationary targets is activated, the unit still tracks the stationary targets and they “count” toward the 100-target limit.)

3. Over the last several weeks of real-world use, I found that there were >100 targets within 2.1 to 2.2 nm of my boat. This means that nothing beyond about a 2-mile range was shown on my Axiom MFD.

4. A primary use of AIS around here for those of us in slow sailboats is to avoid fast-moving commercial ships and ferry traffic and to help decide when and where it is safe to cross or operate near the Vessel Traffic System and ferry routes, especially in poor visibility. So, it’s necessary to be able to see, track, and identify these ships on AIS at least 10+ miles out. AIS allows you to track them even when they are not visible by eye or radar, such as when blocked by an island or other land mass, coming out of a harbor, etc.

5. I cannot stress enough what a problem this limitation is for those customers who purchased their MFD expecting to use its AIS plotting ability as a navigational tool along with its ability to show charts and radar. It’s analogous to a plotter only being able to display radar targets out to a 2-mile range even though the scanner is receiving targets out to 15-20+ miles.

6. Because of this limitation, I now find myself using my new Axiom MFD as a radar display only and having to prop my iPad up next to it to plot AIS targets.

7. There is no warning to the user that the 100-target limit is full and that vessels beyond X miles cannot be shown. Had I not discovered this subtle limitation, I could easily have gone to cross the shipping lanes in fog, consulted my Axiom AIS and concluded that the coast was clear only to have a 20-knot ship pop up on my display only 2 miles away and bearing down on me.

8. I’m sure when the software was first written, a 100-target limit was ample, and it might have been hard to foresee the coming explosion in the popularity of AIS with recreational boaters. So I’m really hoping that this issue can be addressed just as soon as possible.


Thanks for your additional comments on this feature request.
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