Can anyone clear this stuff up for me? I’m new to side imaging and still have questions. You have the feet to each side of the transducer on the bottom of the graph, and you have the water column depth to each side. Where I’m having trouble connecting dots is, if you’re in 25 ft of water, the water column/floor is going to be at the 25 to each side. So how do you determine how far to either side a piece of cover is from the boat if less than 25 ft away? If the floor is at 25, and something is only 10 ft to the right or left, how does that look? I know when you see it on both sides, it’s more so under the boat, or somewhat leaning more to one side or the other depending on the return strength from each side.

I’ll be honest, I didn’t read the question real thoroughly. When your scanning 100’ out to the side and if you’re in 25’ depth of water, then you’re only really shooting out 75’ to the side. Something only 10’ to the side would appear under you, split on both screens usually. Hopefully I read the question right.

There are a lot of good videos on you tube that are available that can help you regardless of the unit or brand you have. I still watch some over again just for fun and or a refresher. I have Garmin's and their site has a bunch of how to videos to help me learn my units. Im sure Lowrance and Hummingbird do as well. As far as seeing something from the side, you have to take the depth of the water column away from the sidescan distance setting. The easiest thing I do is to pause the sonar and put a waypoint on it. Even if you don't want to put a way point, you probably can pause the sonar and put a pin on it which will measure the distance. Also if you see it on your side imaging its behind the boat.

I’ll 2nd the you tube videos. They are a lot easier to learn from than just reading the manual supplied by the manufacturer.

Knew it was dumb lol. It makes perfect sense now with subtracting the water column depth from the distance.Thanks for clearing that up fellas 👍

Something 10' to the side would be displayed at about 35' since the water column is included in the view.

One more thing, stuff displayed on SI is not horizontal distance, it is SLANT RANGE distance from the transducer.

Yeah what Wayne said.

But I think my Lowrance reads differently, definitely not near as accurate as his images show. Wayne would it make any difference using 800 vs 455, going old school here.

why are y'all saying to add or subtract the water column?


https://www.humminbird.com/learn/imaging/side-imaging

Side Imaging, Side Scan, SideVu, SideVision is all the same and works the same.

Generally, the frequency determines how much range you can get and the quality of the images.
Just like 2D sonar, the lower the frequency, the more depth capability you get and the less detail you get.

Common sense, since part of the image is the water column, if you want to figure out how far a subject is from the transducer, you have to delete the DEPTH to get the RANGE. That is what the folded illustration in the link is doing.

With Humminbirds, the closest you can get visually to distance (eliminating calculation), is turning off the water column (Contour Mode) so only the bottom is displayed. That is a technique where bottom stuff is more important than suspended stuff (SAR is an example).

Wayne, my Lowrance doesn’t remove the water column like your bird does. What would something look like on your SI if it is directly straight down?

For example, on the center bridge pylon above, how would it show up on your screen? I imagine you have a picture for reference, if you can understand what I’m even asking. Not sure I’m wording it clearly.

Yes I understand your question, just don't have a similar example.

Anything in the water column below the transducer would not be displayed since there is no water column. Don't have any images of tall stuff in the water column. Playing back Simulator that has a couple of rock piles, it looks like with with Contour Mode on and off.

just made me curious after seeing the water column feature off. Pretty cool feature to show more of the screen.

That hummingbird video is a good one Hop!