That setting for water level offset on the map settings tab is to adjust every track on your entire project with one click. However, it is not an actual elevation adjustment. Its a number that you wish to adjust your existing tracks with, all of them in the project.

The way I've done it is adjust every track as I import them from the GPS to full pool in the track editor. I have done this for 8 or 9 years, beginning with Dr. Depth before I had RM. Then, every track I have stored reflects the full pool of the lake. Now I can check lake elevation before making a map. If the lake is down 20 feet, I enter -20 in the lake level offset box on the map settings. I used to do this with Dr. Depth. It has been working perfect with V2 yesterday and today.

In order to use the water level offset, all your data has to match some baseline water level. I use full pool as my baseline, and adjust from there. If you collect data on different days, at different water levels, or at different tides, you've already been needing to do this somehow so your overlapping and adjoing data matches up. Now you just have to know your baseline and the water level you want to make a map for, and adjust from there. Hope this helps and I understood your question.

Thanks for this I know Matt is ready to pull is hair out about now
Can I start to create a new map and just edit a few tracks at a time ,I have about 20 with about 120m ea you are saying editing each one right ? I mean like sonar log or each dot ?
Thanks again for your info

You set the water level first on each track. The whole track, not each dot. That's your base level. Then when you create the map itself, you can use the water level outtset for the project based on the difference between your tracks, and the actual water level.

Thanks TJ
I do appreciate the replys
If I go to workplace I can see the tracks, I brought down and then right click on ea one and go to Edit offset and chg it to 723 (pool)So when I did this the sonar log that was 82ft is now 802 It added the track that was reading 82ft .Do I now go back into track edit and subtract the 82 to make it 723 ?? and the when I create a map I can adjust the water line to + or -
I am sorry being a pain in ---
Thanks again

Are you trying to make it display 723 feet deep? I think I'm confused as to what the 723 number is. Depth or elevation?

You need three variables. 1. Normal full pool elevation of the body of water, (or a number to use for a baseline level). 2. How far up or down the water was from the normal full pool elevation when you recorded the data. 3. The current water elevation, or elevation you want to use for your map.

So, say the elevation of the lake when full is 100 feet. On the day you recorded data the elevation was at 80 feet, down 20 feet. For that data, when you first import it, you edit the water level in the edit window for each track and add 20 feet to it, so that the data reflects what the depths would be at 100-foot lake elevation.

Now, its time to make a map project. Today, the lake is now at 70 feet. That's 30 feet down from our 100 feet baseline. So in the project settings window, you set the "Water Level Offset" to -30 (negative 30) because the lake is 30 feet lower than our 100 foot baseline. Remember that above, we adjusted our data to the 100 foot baseline, where it will always be saved. That's why we use -30 for the offset.

Your map will now reflect accurate depth when the lake is at 70 feet. Just change the numbers for your body of water. The beauty of this system is that you can create a map for any lake elevation you want using the same data since every track is corrected to the baseline full-pool level first, and saved on your computer (and backed up!) forever.

Normal full pool elevation of the body of water 723 that is when the lake is at pool
the date I recorded was Last year ,I didn't set anything then so the track said it is 82ft
that's why I went and change the track to 723 which is pool I guess that is wrong ? I don't know at that time what the water level being pool was all I known is the track said 82 ft
ft now

You have to find out what the elevation was when you recorded the track that's 82 feet so you have a reference for that track. As the elevation of the lake changes, then the depth of every track changes since it records bottom depth from the surface and not bottom elevation of the terrain. You need lake elevations for your data in order to have a map with accurate contour numbers.

The first "must" is knowing the lake elevation when the data was recorded. I can go to a site here in the US for my lake and retrieve lake elevation information for any date in the past.

I am able to find the elevation at the time track was made
when you say elevation you are referring to pool I know it can be something else
I did that and it was 703 ft and the track was 82ft

Elevation is the height of the surface of the water above sea level. Like altitude in an airplane, only on land its called elevation.

So, the track was 82 feet. The elevation was 703, 20 feet below full pool which you said was 723. So when you import your SL2 track from your sonar/gps, you will enter 20 for Water Depth Offset. Then, your track will reflect the lake at full pool, forever if you save it.

When you create your map project with that corrected track (that you have stored to add to your asset list when you start a project and then "add to project"), you can subtract however much the lake is down from 723 in the editor. (The great new feature of RM2) If the lake is full, at 723, or you want your map to show the depth of the lake at full pool (723), then you don't need to adjust for water level offset at all in your project.

If the lake is down 10 feet, and is at 713 when you go fishing and you want your map to show that, then enter -10 in the map settings before you generate your map. Just remember, you are always working with "full pool" tracks once you import them and store them after converting to full pool.

I want to thank you a lot
I notice when I did the import tracks in RM2 it change the tracks to the date 3/13/2017 ?
so I went back and rename the tracks to reflect, so I know later they were made in 2016
I didn't store them yet there still in the asset list ,so I need to do that ?
Do I do the offset in my unit Lowrance gen 2 touch ? I did it when I import to RM2 and before I created the project, Thanks again I might not be doing the right steps ?

I rename my tracks to reflect the exact day I recorded them, yes. I rename and store them before I ever load them to the asset list. Then I import and convert them using Reefmaster. When you import them, you open each file in the edit window to type in the water depth offset.

thanks I got it !!!!!!!!!!! that's what I did
I notice when I import the tracks then went to the asset list it change the date and also added sl2snt on some tracks ?