Locating structure / fish

[Slowboat]

I didn't realize that. So if I am understanding correctly, essentially there is no real benefit to marking a way point using the cursor on the screen instead of simply marking the boats current position? Why even have the feature?

I think CrappiePappy point is just like when your seeing something on the screen doesn't mean what you are seeing is directly under the boat. So when you you drop a waypoint the waypoint is marking your boat on top of the water or where it was at that time. This will still get you back to that spot where you saw whatever your marking. The sonar/gps cannot pinpoint under water.
Side imaging changes these rules and I won't comment since I don't use it.
There are many good videos of guys using gps sonars and marking structure. I think actually seeing it work in real time helps get a grasp on the technology. Of course they use the good stuff!

[Dave and Lynn]

Sounds like you have the perfect setup for long line trolling for crappie. Gps unit would really help mark spots as you troll along. Having the gps unit on your finder helps in real time for what you see on the screen and what you have marked. As said previously, when you see it and mark it you have passed it by, but it gets you in a general areal. If the finder has tracking on it you can save that and make the same trolling pass to a gps mark and stop short of the mark and and move slowly to it. As soon as you see the brush pile on the screen throw out a marker and you are as close as you can be. Good luck.

[Slow Retrieve]

I think CrappiePappy point is just like when your seeing something on the screen doesn't mean what you are seeing is directly under the boat. So when you you drop a waypoint the waypoint is marking your boat on top of the water or where it was at that time. This will still get you back to that spot where you saw whatever your marking. The sonar/gps cannot pinpoint under water.
Side imaging changes these rules and I won't comment since I don't use it.
There are many good videos of guys using gps sonars and marking structure. I think actually seeing it work in real time helps get a grasp on the technology. Of course they use the good stuff!

I understood that was his point and it still raises the question I asked. Why do they even have the feature of marking off the cursor position if it doesn't do anything different than marking a waypoint from your current position?

I'm far from an expert but it doesn't make sense that they would create that function in the units if it doesn't do anything different. Here is Lowrance's wording in my manual (emphasis mine):

New Waypont

Places a waypoint at your current position or at the cursor position.

[vic n]

I understood that was his point and it still raises the question I asked. Why do they even have the feature of marking off the cursor position if it doesn't do anything different than marking a waypoint from your current position?

I'm far from an expert but it doesn't make sense that they would create that function in the units if it doesn't do anything different. Here is Lowrance's wording in my manual (emphasis mine):

New Waypont

Places a waypoint at your current position or at the cursor position.

Your boat is moving. You drive over a tree, or brushpile that you want to mark. You don't stop your boat and try to hover over the spot while you try to mark it. Your boat keeps moving, but you maneuver the cursor to the spot on your screen (history) that is closest to the cover. Actually you can see how far behind the boat your cursor is if you look at the read out on screen. The discrepancy comes because the waypoint will correspond with the location of the head unit, NOT the transducer (the head unit holds the GPS). If you use a separate GPS puck located at the transducer, the waypoint will be right on. For example, if you have a 40' boat with the transducer on the transom, and the head unit at the bow, all of your waypoints will be 40' off.

[Slow Retrieve]

Your boat is moving. You drive over a tree, or brushpile that you want to mark. You don't stop your boat and try to hover over the spot while you try to mark it. Your boat keeps moving, but you maneuver the cursor to the spot on your screen (history) that is closest to the cover. Actually you can see how far behind the boat your cursor is if you look at the read out on screen. The discrepancy comes because the waypoint will correspond with the location of the head unit, NOT the transducer (the head unit holds the GPS). If you use a separate GPS puck located at the transducer, the waypoint will be right on. For example, if you have a 40' boat with the transducer on the transom, and the head unit at the bow, all of your waypoints will be 40' off.

Well that makes sense, and I have always understood any waypoint will only get you within maybe ten feet or so depending on the depth and never has pinpoint accuracy but if you are trying to mark a specific underwater structure marking off the cursor should still get you closer to your intended mark then marking off the boats position wouldn't it? There has to be some difference when doing so, no? It can't be just marking your boats position either way.

Thanks for the input

[CrappiePappy]

Well that makes sense, and I have always understood any waypoint will only get you within maybe ten feet or so depending on the depth and never has pinpoint accuracy but if you are trying to mark a specific underwater structure marking off the cursor should still get you closer to your intended mark then marking off the boats position wouldn't it? There has to be some difference when doing so, no? It can't be just marking your boats position either way.

Thanks for the input

Yes ... marking the waypoint with the cursor is simply marking the spot that you've already passed. The GPS program knows what the coordinates of the screen images are, so when you scroll back & mark a spot it will mark the waypoint at that point in the history of your boat movement.

The fact that the GPS program "knows" where the antenna is AND where it WAS in the screen image history ... makes it able to mark a waypoint whenever you see a spot you want marked, whether you are just seeing it come on screen OR it's still in the history of the scrolling screen.

It doesn't mark your boat (current) position, when using the cursor ... it marks the spot where you passed over that cover. You're right, that it would be useless to have/use the cursor if it only marked where your boat (antenna) was "at that time".

Whether or not you have the cursor showing on your screen, the GPS program is using it to pinpoint your antenna's location. So, in essence, you're actually using the cursor whether you can see it or not. If you didn't have the capability of the cursor, and you passed over a spot you wanted to mark, but didn't mark it as soon as it showed up on the screen .... then you'd have to turn around and find the spot AGAIN, to be able to mark it.

Not everyone likes to have the cursor on the screen all the time (I don't) .... but, if you pass over something you want to mark & didn't notice it or get to the buttons fast enough to mark it before it starts going off the screen, then you can scroll back & mark the spot with the cursor ... and that "spot" will be where the GPS coordinates says it was. Doesn't matter where the "boat" is ... it only matters where the antenna IS or WAS, depending on if you mark the spot as you come upon it (where the antenna IS) or use the cursor to go back in time to where you were when you passed over it (where the antenna WAS).

... cp

[Slow Retrieve]

Yes ... marking the waypoint with the cursor is simply marking the spot that you've already passed. The GPS program knows what the coordinates of the screen images are, so when you scroll back & mark a spot it will mark the waypoint at that point in the history of your boat movement.

The fact that the GPS program "knows" where the antenna is AND where it WAS in the screen image history ... makes it able to mark a waypoint whenever you see a spot you want marked, whether you are just seeing it come on screen OR it's still in the history of the scrolling screen.

It doesn't mark your boat (current) position, when using the cursor ... it marks the spot where you passed over that cover. You're right, that it would be useless to have/use the cursor if it only marked where your boat (antenna) was "at that time".

Whether or not you have the cursor showing on your screen, the GPS program is using it to pinpoint your antenna's location. So, in essence, you're actually using the cursor whether you can see it or not. If you didn't have the capability of the cursor, and you passed over a spot you wanted to mark, but didn't mark it as soon as it showed up on the screen .... then you'd have to turn around and find the spot AGAIN, to be able to mark it.

Not everyone likes to have the cursor on the screen all the time (I don't) .... but, if you pass over something you want to mark & didn't notice it or get to the buttons fast enough to mark it before it starts going off the screen, then you can scroll back & mark the spot with the cursor ... and that "spot" will be where the GPS coordinates says it was. Doesn't matter where the "boat" is ... it only matters where the antenna IS or WAS, depending on if you mark the spot as you come upon it (where the antenna IS) or use the cursor to go back in time to where you were when you passed over it (where the antenna WAS).

... cp

OK, thanks I think I understand what you meant now.

So essentially if you were sitting still or trolling very slowly on the water using the cursor to mark something you currently see on the screen would be the same as simply marking the boats current position. The only benefit to using the cursor would be when you are using the trackback feature.

[CrappiePappy]

OK, thanks I think I understand what you meant now.

So essentially if you were sitting still or trolling very slowly on the water using the cursor to mark something you currently see on the screen would be the same as simply marking the boats current position. The only benefit to using the cursor would be when you are using the trackback feature.

In a nutshell, yeah !! You've got it !!

... cp

[vic n]

Well that makes sense, and I have always understood any waypoint will only get you within maybe ten feet or so depending on the depth and never has pinpoint accuracy but if you are trying to mark a specific underwater structure marking off the cursor should still get you closer to your intended mark then marking off the boats position wouldn't it? There has to be some difference when doing so, no? It can't be just marking your boats position either way.

Thanks for the input

I think actually the depth doesn't create the discrepancy. It's more the result of civilian GPS. We don't get military accuracy, so when we return to a waypoint we may have a built in error from our head units not being located at the transducer PLUS the accuracy (or IN-accuracy) of civilian GPS added to that. That said, I don't have any trouble locating a well marked waypoint when I return to it.

[Slow Retrieve]

I think actually the depth doesn't create the discrepancy. It's more the result of civilian GPS. We don't get military accuracy, so when we return to a waypoint we may have a built in error from our head units not being located at the transducer PLUS the accuracy (or IN-accuracy) of civilian GPS added to that. That said, I don't have any trouble locating a well marked waypoint when I return to it.

I always thought that if you were in deeper water, and therefore the frequencies cone was spread larger to the bottom that there could be a larger area to where the structure was that you saw and where your boat may be positioned above it which could result in a farther distance from your waypoint.

As you can probably tell by now I am far from an expert on this so I understand I may be wrong about this.