Topic: 998 GPS Marking Question

[reelnmn]

OK So I've had my 998 for about a year now and absolutely love it.  However, I have one consistent issue that I'm hoping someone can help me resolve.

Let's say I'm idling along looking at side imaging and spot a log, rock pile, or fish.  I scroll over top of it and hit mark.  Then try to idle over it to try and get a different view in down imaging.  However, my GPS is always off.  I haven't been able to determine if it is consistently off one direction or the other because I usually can't find the object I was looking for.  I have good satellite connection so I'm thinking my side imaging transducer isn't shooting completely horizontal causing inaccurate marks.

Any suggestions?

Chris

[sonar2000]

You are correct that the mark is not a relocate accurate point. It is close but not dead on. It will get you close and then you will have to refind. These slant range algorithms are not as accurate as they can be.
Marking a GPS position direct from the GPS part is fairly good but the SI position is a bit off. Another thing to consider is where the transducer is located as compared to the GPS puck.  This can put the actual position off a bit also..

Chuck

[newkid4si]

When traveling from your original position to the marked position,
leave the view on SI instead of DI. This way you will know if the
target is left or right of your course.
Depending on your original setting, try reducing the SI range also.
Sometimes you have to sneak up on these targets.

         Mike

[ITGEEK]

I've also had problems getting exactly back to a
newly marked waypoint.  If the wind is blowing then
it's almost impossible.  Once I had a drop-off marked, and
all I wanted to do was to throw a marker buoy over it.
I could not get back over that spot to save my life.
I tried for about 30 minutes, and finally gave up.

One suggestion is to zoom your map in as big as it will
go (and still be able to see the waypoint).
Keep zooming in until you can't anymore.
This will show you the most map accuracy.

[Bob B]

Where is your GPS antenna mounted .....how close is it to the transducer?

[reelnmn]

The GPS puck is mounted 6 inches forward and 18 inches to the right of the transducer.  Thank you all for the responses...I'll definitely try a few of the recommendations next time out.