Navionics
With Lowrance your options are limited....
1. You could use the Lowrance Insight Genesis, which from what i've heard the map of Sak isn't very good, but you can create your own maps to improve the current map
2. You could use Great Plains mapping i believe, I have never used it so I can't speak to it.
3. Lakemaster no longer makes lowrance chips, their old chips(at least the 1 I have) are no good on Sak. The new maps for humminbird units are pretty good for the most part.
4. Navionics is the map that I run, but it does lack good shallow water contours since it was mapped at a much lower elevation. The maps are getting better because you can upload sonar logs to Navionics and they update the maps, and if you have freshest data(free for 1 year after purchase of a card) you can update your chips. It usually takes a couple days- a week or so for the updates to be processed. But this doesn't come without problems because Lowrance changed its format on sonar logs and tracks so Navionics isn't able to process it. If you have an older Lowrance unit that you have not updated lately you could use those gps trails to upload to Navionics. So basically it is difficult to upload sonar logs from lowrance units, but i will tell you how I can log sonar for updates running only Lowrance.
In order to get logs I use the Navionics App and connect it to my sonar unit using the Gen3's internal local wifi. Then it sends data to the App and creates a sonar chart live right on your phone. After you are done making the SonarChart Live and close the app it will send that data to navionics so they can put it in their updates and you can then put in on your map chip. It's not the most user friendly option but it works. You need to have a way to charge your phone and a wifi capable sonar unit. Gen2 lowrance has a wifi add on, it comes built in on the Gen3. The vexilar sonar phone($169 i believe) can do the same thing. Navionics has some agreements with some companies like Raymarine allowing this live chart to show right up on your graph, here's to hoping they can get lowrance to allow the same... I have included a link to my facebook page that shows some of the sonarchart live.
https://www.facebook.com/LiebelsGuideService/posts/1002727856445415
