Navionics . . . I'd look elsewhere . . .

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

On the H20 one of the pages will tell you how many satellites you have and an EPE number. This EPE number is how accurate your GPS is with the current satellites you are using. I have seen numbers as bad as 350 and as good as 15 which is feet of accuracy. Seems I get better accuracy when I have WAAS. I cant always get this satilite and when I dont have it my accuracy goes way down.

Thanks, I never even thought of how the satellites accuracy can vary depending on which ones the unit is linked to.

I have two other GPS's. One is Garmin Emap handheld and the other is a TomTom Navigator version 6 that runs in my Palm Treo 600 handheld.

They both seem to read only 3 or 4 satellites at a time. I was used to the level of their accuracy as to only having to be accurate enough to give you the turn for the next exit or they only need to be within a block or so when you are driving around some neighborhood.

But on the water it's a different need for a higher level of accuracy.

Do you think a full blown radar setup will look too tacky on a 14' 9" auminum boat :rolleyes:
 

dingbat

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Re: Navionics . . . I'd look elsewhere . . .

A map datum describes the model that was used to match the location of features on the ground to coordinates and locations on the map. If your GPS is using one location and the map software is using another, then positioning errors like you are experiencing are expected. Since you can?t adjust the datum of the map, you need to change the reference point your GPS is using.

Watch out when converting locations from paper maps to GPS as well. A lot of maps are done in using datum NAD 027 and GPS is typically set up for WGS084. In the continental US there can be 200 meters of difference between the two at any given location.
 

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

A map datum describes the model that was used to match the location of features on the ground to coordinates and locations on the map. If your GPS is using one location and the map software is using another, then positioning errors like you are experiencing are expected. Since you can’t adjust the datum of the map, you need to change the reference point your GPS is using.

Watch out when converting locations from paper maps to GPS as well. A lot of maps are done in using datum NAD 027 and GPS is typically set up for WGS084. In the continental US there can be 200 meters of difference between the two at any given location.

Thanks dingbat.
That's exactly what I needed clarification on in adjusting the map to the GPS signal. That makes sense that we can match the GPS location and the mapping software.

If this works it will save me big bucks on the radar setup ;)
I realized anyway that radar does not read the contours or submerged rocks etc.

So do you the SD card info somewhere gives me the mapping code so I can match it up with the GPS reference location. Is this what appears under my advanced setup tab and I'll be able to adjust it there? The manual only shows that I can adjust the latitude and longitude under that tab. How do I match that to the software's correct datum?

Sorry for all the questions, but I would like to get the unit working as accurately as it will allow.

It just stopped raining outside. I'll go check out what that screen looks like. It will give me a chance to see what the Fish and Chips card looks like too!

Update: I did see under tab advanced (it is buried under the "user mode" tab) the ability to select 3 different GPS positioning codes. One would think the unit would be smart enough to auto select the correct one for the mapping card you insert. I don't see any way of knowing what the SD card map code is. I guess I'll just have to be underway and watch to see the next time my boat shows itself on the map riding on the land and go into that setting and try changing to one of the other two!

On the Fish and Chips. I see nothing happening when I insert the SD card in and have the cursor over Lake George which is supposed to be one of the enhanced lakes on the Gold version. Only goes down to 1 mile and then into overzoom. I just cursored over to the oceans and that is what it's for as it does show enhanced bottom contours up and down the coast. It appears to be exactly what I assumed it was which is that the Gold version of Navionics East coast is just that . . caostal charts up and down the East coast with a few inland lakes tossed in that overlap a few regions. These inland lakes even though they say they are enhanced on the Gold card show very little info. At least not as much info like contours, ports etc as the Hot Maps Premium version does.

Too bad it's useless for my needs. That Gold version is the coastal version and this Fish and Chips only shows the coastal regions.

Navionics could have solved everything by making their Platinum all inclusive. So what if the 3D enhancements don't work with all units. The Platinum version which was not designed to work with my particular unit at least gave me the contours like the Hotmaps premium version does now. My only choice now is to dump the Fish N Chips card and the Gold East cards on Ebay to try and recover a portion of my investment. I don't see myself in the near future using a boat on the coast unless I move or buy an SUV to trailer a bigger one.

I was really led astray by Navionics customer service and they would not rectify their error fast enough for my satisfaction anyway. Not a company I will do any future business with . . . just my unfortunate experience.

Thanks for any continuing input that might be able to get my unit and the Hotmaps Premium card little more accurately matched up since for now I'm forced to keep, unless I finally dump the whole system on Ebay and go with Garmin, I'm already leaning about 75% in that direction now anyway.
 

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

I've never seen a GPS that didn't allow you to change the map datum. I'd check to make sure just in case

From page 116 in your manual

Map Datum allows you to change the map coordinate system used by the
Fishing System to match those of a paper map. The Map Datum menu choice
is only available when User Mode is set to Advanced (see Setup Menu Tab:
User Mode).
To change the Map Datum setting:
1. Make sure you are in Advanced User Mode, then highlight Map Datum
on the Navigation main menu.
2. Use the LEFT or RIGHT 4-WAY Cursor Control keys to change the Map
Datum setting. (Default = WGS 84)

I still think dingbat, what they are referring too is that you have the ability to match the datum to a "paper" map. The Hummingbird must have the ability to read the card and set the correct map datum setting . If I can't get the card's map matched up with the unit GPS signal correctly myself I'll call Huminbird's customer support to see if they can help me to do this.

That's why page 16 says just insert the card and the map loads automatically. It would say you need to set the datum setting next if it was not automatically set.

Sunday note: Today with the hotmaps premium card in the unit it was running pretty accurate on the Hudson River river, so I forgot to try out the other two GPS signal settings. One of the other poster could be correct on it might depend on which set of satellites the unit locks on to!
 

gonefishie

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Re: Navionics . . . I'd look elsewhere . . .

I know the maps are all the same. But I bet the same map aligns better on your Lowrance than they do on my Humminbird.

Thx for your input!

They sure do! Navionics products were designed to work with Lowrance first and foremost. If your graph datum setting is WGS084 then don't change it because that's what the map use. That setting should be the default for all unit sold in the U.S regardless of make. Just FYI, before you go through the troubles check out this link.
http://www8.garmin.com/cartography/inlandvision/disclaimer.html
I'm afraid you will see the same thing and the same capabilities limits. Water is water my friend, it doesn't matter if Coke or Pepsi bottled it. It's still water.
 

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

I had time today to check out the 3 different GPS position settings on the river today.

Passed by many buoys on different settings and it looks better now on one of those settings. At least the buoys are on the correct side of the boat today and it did not show my boat traveling across the land masses :D

I think it's what another poster had said in that it all depends on which satellites the unit happens to lock on to.

Thx for all who responded.
 

bassboy1

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Re: Navionics . . . I'd look elsewhere . . .

What I want to know, is why you spent an extra 500 on a unit that was primarily designed for advanced anglers, when you hardly fish? The 797 is a GREAT unit, but it has the side imaging, which is absolutely the best in fishing sonars these days. For 500 ish, you coulda gotten a good GPS, as that seems to be what you are looking for.
 

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

What I want to know, is why you spent an extra 500 on a unit that was primarily designed for advanced anglers, when you hardly fish? The 797 is a GREAT unit, but it has the side imaging, which is absolutely the best in fishing sonars these days. For 500 ish, you coulda gotten a good GPS, as that seems to be what you are looking for.

I do fish a lot from time to time. It's just that since my boat is only a few months old and my Wife really enjoys being on it, I've done more cruising this season than fishing. We've logged way over 100 hours on the water past 2.5.months (GPS keeps track of the hours).

Funny you mention this because she just asked me "if you don't fish that much why did you buy a fishing style boat?"

Wife will fish when they are biting, but gets bored moving so slow trolling.

I do mostly trolling or casting for bass while drifting along a shore line.

I figured my Son and Daughter would do a lot more fishing with me after I bought this new boat but they just bought Kayaks so they are always on those.

Sometimes it's lonely out there on a boat "always" by yourself, so since my Wife likes being on the boat so much I have been cruising a lot more.

You are right about how I spent the extra $500 on the GPS/Fishfinder unit . . . I've mentioned this in another thread I started:
http://forums.iboats.com/showthread.php?t=207468
This is where gonefishie suggested how I should look at the combo units.

You are correct as I originally went out to purchase a $500 unit that had a quick disconnect type mount since I have an open boat and trailer alot.

I went to my dealer and the only Humminbird they had left was the $999 model.

I took it out of the box to see if it would not be too big for my dash and it fit in the spot perfectly. I knew most web site sold this unit for $925-999, I thought they would give me 10% of as they did with other accessories but they could not do it with this item.

So I know I would have spent 5 to-$700 when I finally decided, but many on the websites were already on back order, so I did not want to have to wait another few weeks to get one in and risk running aground in unknown waters and I had this $999 one just sitting on my dash and looking so fine . . . I took it.

I figure I'll grow into it rather than grow out of it anyway.

I used to fish with various buddies years ago and that was always fun but I don't want to have a buddy depend on me to go fishing and I have to keep passing him up because my Wife wants to go cruising.

My 14.9 boat can have 4 seats in it, but it's a lot more comfortable with 2.

Water was so warm around here in most lakes this year I found the fishing to be slow anyway. Each time my kids went with me we caught a lot less than we have in other years, so they were bored.
 

AndyL

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Re: Navionics . . . I'd look elsewhere . . .

I understood that changing the datum in the GPS would only apply a correction to the tabulated LAT/Long. Your position displayed on the plotters map should still be accurate. The error would only show up if you pulled the LAT/Long off the unit and tried to plot it on a paper chart that was on a different datum. Incidentally there are an awful lot of big ships running arround with full classification approval that do not carry any paper charts at all.

Pretty scary!!
 
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Expidia

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Re: Navionics . . . I'd look elsewhere . . .

I understood that changing the datum in the GPS would only apply a correction to the tabulated LAT/Long. Your position displayed on the plotters map should still be accurate. The error would only show up if you pulled the LAT/Long off the unit and tried to plot it on a paper chart that was on a different datum. Incidentally there are an awful lot of big ships running arround with full classification approval that do not carry any paper charts at all.

Pretty scary!!

That's what I thought too from another poster who said the correction feature under my advanced user mode is for paper map conversion use.

What I've found is it depends on which satellites set the unit locks to as to the accuracy that day on the water.

Would like to know if I see it too far off like before, if there is a way to reset the unit to track other satellites?

I know of an acquaintance with a new 45-50 cruiser who ran his ship aground and did much damage to his props because he relies only on his several thousand $ GPS unit. The buoy had been moved out of position in the channel the first time. I think he done this twice already!

On the Hudson river on Sunday I was trying to adjust the settings cruising along at 15 mph on the GPS as I went past islands and buoys. I entered a large bay with a marina at the end which I've been through before (but at high tide) 15 seconds later while viewing the satellite mode I ran aground. I thought I was screwed and saw a big tow bill coming up. It was going to be dark in 30 minutes too. Tide drops very fast. I've seen many boats this year way out on the beaches waiting hours for the tide to come back in.

Luckily, the Hudson is very muddy and sandy so I was able to bring the prop way up and walk to the bow and the boat finally started chugging out. I was lucky because I could have been moving into even shallower waters towards a rising sandbar too.

I knew what the paint on the prop was going to look like. Have over 100 hours on this new outboard and not a mark on it (until Sunday). Had to spray paint it yesterday. At least there was no damage to it.

Moral is I won't take my eyes of the GPS again while under way. A 6 foot tide makes a big difference on a river!

This is exactly why I bought this GPS and stupidly was trying to adjust it while entering a bay :(
 

ddennis

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Re: Navionics . . . I'd look elsewhere . . .

I am looking at getting the 797C2 SI combo with the navionics bundle also..now that you have this sorted out...how do you like the unit? I only fish freshwater here in the southeast (Ga, TN, La, FL) So I am mainly looking at the sonar features, but I am also interested in the GPS mapping as well...seems like the is the best of both worlds in one unit.. thoughts?
 

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

I am looking at getting the 797C2 SI combo with the navionics bundle also..now that you have this sorted out...how do you like the unit? I only fish freshwater here in the southeast (Ga, TN, La, FL) So I am mainly looking at the sonar features, but I am also interested in the GPS mapping as well...seems like the is the best of both worlds in one unit.. thoughts?

Hi ddennis

Yes it's been a long road but it's not the unit as much as the salespeople you talk to don't know squat so you have to do your own homework like I did. I mainly went the Humminbird model because they have the best quick disconnect feature of all the major brands. You can't go by Navionics poor customer service because I'm sure the rest are just as bad. No one wants to spend the money to train them properly.

Humminbirds reps are very good as I've had two issues solved by them right away as they sent me the replacement parts quickly and free.

Navionics (the mapping company) are the ones that would not swap my new card back even though their rep gave me the wrong version that I needed.

I paid $999 plus tax and another $199 for the mapping card.

You could save probably another $100 on the web for the unit. And buy a 2006 card (really the same as the 2007) as I just picked one up off Cabelas website for $59 for the Hotmaps Premium card. The only difference I see is in 2007 is 10,000 lakes instead of 2006's 8,000 lakes. I only need a half dozen or so and they are on both version years anyway.

On the sonar . . . I bought this model as it was the only one the dealer had left in stock and for the few hundred difference I figured what the hell, it would be interesting to see how good the side scan sonar is. And I can always grow into it.

It really does show a 3D like picture of the bottom because of the multiple beams. But I've been so happy cruising around big lakes on my new boat this summer I really have not had too much experience scanning for bottom structure because I didn't fish much. My last boat had a 10 hp Mercury on it. This new Merc 40 hp allows me to be totally free to where or how far I want to go now. So cruising around has been my first priority.

I was fishing for Lakers in 150 feet of water when I did fish this summer and much of that bottom is just flat. And the fish were hanging about 45 feet down.

If I were looking for structure where the Bass would be hiding this unit is perfect. But in scanning mode you're only moving along about 3 - 6 mph.

So with my new 40 hp I did very little boating time at 3-6 mph. I've been locked into low speeds for 5 or 6 years (previous outboard was a 5hp)
So this year I let it all out. Love cruising around at 15-20 mph now with top end around 32.

If you can afford it go for it. If dollars are tight you can get a decent combo unit for 400-600 dollars. Humminbird has them too. That's what I was originally looking at.

If you really need sidescan because you are big on bottom structure you will be happy with the 797. But other than side scan I don't think (from my research and what I've read on the forums) that the 797 is really worth twice the price, since as the prices climb the comparable Lowrance or Garmin units are of equal build quality and screen clarity.

The Platinum cards from Navionics only work in units like the 997 which are $2000 and feature a bigger screen. With Platinum you can see aerial views of approaching bays and areas in 3D. No big deal to me because there are area lake books that will give you the same views for a lot less than $2000.

All in all I think the 797 is worth it even though I have not sufficiently put it through it's paces yet. The Hudson River which I'm on weekly when I'm alone and have time to scan around, does not have a lot of bottom structure to view.

PM me and I'll give you my cellphone # or my 800 # at work and you can call me directly, if you have other questions.
 

John_S

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Re: Navionics . . . I'd look elsewhere . . .

As you use the side scan more, would be interested in how accurate it is. The photos in the ads look very impressive. But, I am familiar with Humminbirds first foray into 3D, which was hyped more than what it was capable of.
 

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

As you use the side scan more, would be interested in how accurate it is. The photos in the ads look very impressive. But, I am familiar with Humminbirds first foray into 3D, which was hyped more than what it was capable of.

Don't know about their 3D foray but sidescan seems to do what it says.

The pics on their site seem pretty accurate from my experience so far only they look much brighter. The manual is loaded with pics too.
See if you can download their manual, they all seem to be actual scans.

In taking another look at Humminbirds website's sidescan pics the only difference I see is that they probably enhanced to look brighter. It would be interesting to call customer support and ask if they are actual unretouched scans. Since the pictures are made by sound waves the light or lakes clarity might also make some difference.

I bet it would look super when scanning along the "ocean's" bottom structure like a coral reef.

Lakes and Rivers are pretty boring when compared to the ocean. I know this from doing scuba diving in both years ago. Most lakes are pretty gross and erie to dive in because of all the alge, weeds and poor visiblity. But sidescan sonar should still give a somewhat decent picture because it using sound waves not light waves.

I'd like to see if I could duplicate those pics in the lakes and rivers I'm on.
 
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John_S

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Re: Navionics . . . I'd look elsewhere . . .

Back when Humminbird came out with the Wide series, they had a couple of units that had 3D capability. After discussion with owners, I ended up getting a Wide Portrait, that did not have that capabilities.

In one of their ads, Humminbird shows a nice profile of a sunken rowboat. I am generally a skeptic when it comes to marketing ads. Even if they provided actual screen displays, you don't know how much they have "gamed" it by making it ideal conditions. I am not bashing Humminbird, many companies "hype" their products and has become the norm.

While I am not looking for sunken boats, I would be very interested in how well it profiles sunken trees. I fish the Susquahanna River allot, where every flood or high water will move this key structure. It would be nice to easily find them and to know their orientation, trunk vs branches. I also occasionally fish the Mohawk River, but quite aways upstream from you, in the Utica to Herkimer area. The barge section sounds very similiar to your description, ie bathtub like. In these sections, any other structure (such as trees) etc, become magnets for fish.
 

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

For others to see . . . here is the manual of the 797 combo sidescan.

Scroll thru to see pics of what the bottom looks like with sidescan technology. Page 14 and beyond shows great bottom structure pics.

I should be able to replicate pics like these. I'll take a screen shot when I come across structure to show sidescan is not just a gimmick.

The pics of the barge, bridge and swimming pool are cool!

http://humminbird.com/images/PDF/797.pdf

On the Mohawk River: I fished it for the past 30 years. Probably exactly the same where you are out in Herkimer.

Great river as they have stocked it in years past with Norlunges and they keep pulling them out bigger and bigger each year. I troll with worms or even better Crawfish. Bass go bonkers over crawfish.

River is muddy and only 12 feet deep in most of the channel.

I also cast with a chub looking type lure that has a rattle in it and has some orange on it's belly. Rubber worms are great too but I miss a lot of hook sets with the worms as they spit them right out.

I've always found right after a hard rain the fishing is zero for the next few days on the Mohawk. Probably cause the river is muddier and moving faster.

I've caught Northerns in the past by trolling with a worm harness or trolling with a broken Rappala.

One time I was trolling with a worm on the Mohawk and a 25-30 inch Northern broke the water twice after I hooked him and the third jump was right into our canoe. Quite the look of shock on my Wife's face when she saw this alligator looking set of teeth in the air heading for her :eek:

I see people also using big shiners with a float from the shore or off the locks walls going for Northerns, but they get their before day break or real late during the night.
 

John_S

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Re: Navionics . . . I'd look elsewhere . . .

I PMed you about Mohawk fishing. We could end up going way off topic :D
 

John_S

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Re: Navionics . . . I'd look elsewhere . . .

Well, reading the manual helped. What I was interpreting as 3D, is as you said side scan. I do have side scan on my Hummindirds. I have that transducer mounter on my kayak. The side scanning imagagery of mine is not remotly close to what provided on your unit. Mine provides basic detail to be able to tell general contour to the sides, ie is it getting deeper or shallower to my left and right. I use the kayak on small and generally shallow water, so experience is limited to that.
 

Expidia

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Re: Navionics . . . I'd look elsewhere . . .

The manual has some interesting stuff on how sidescan works. It does say it's not a 3D picture of the bottom.

The SideScan transducer is HUGE. I'd like to see you mount this puppy on your kayak!

You could mount it on a swinging bracket and use it as a rudder :D

My Daughter catches a lot of fish on various Adirondack lakes trolling Xmas trees with small pieces of worms from her Kayak going for trout. She caught a "Lake" Trout doing that just last week!

A store in Lake Pleasant "Paul's Bait Shop" it's on route 8 on the right side just before the Lake Pleasant Marina and is a great place to stop in when you are up in that area. He makes all his xmas trees by hand and has many variations. These are of real nice quality too.

DSC03338.jpg
 

John_S

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Re: Navionics . . . I'd look elsewhere . . .

The new sonar won't be going on the kayak. It will be going on the 14' Starcraft/40hp Nissan. http://www.canadalake.org/Starcraftii.html It has one of the old style 3-beams, that is not much smaller than the one pictured. I currently have Humminbird transducers mounted on 3 boats, 4 if you consider the portable unit. The kayak is the only one with the side scan transducer.
 
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