What depths is it handy ? 10' and less? 15'? 20' ? .?.

I use it in all depths. From 1.5' to the deepest holes in the lake. The deeper the water, the farther you can scan to either side with a clear picture.

In this first shot you can see the timber on the left side and on the right side you can the shadows from timber. If you look close you can also see under water vegitation. There's also suspended fish in the tree on the left.



In this shot you see a ton of Channel Cats in 8.5 feet of water. This would look the same if it were only 2 foot of water. Hope these help.

I've found it helpful to about 160ft deep. After that it really becomes tough to use