360 Questions

[brianf.]

Lately, I’ve been using my HB 360 to sharpshoot large predators out in open water.

Here are my questions for you more advanced users: Is there any way at all to estimate how deep the large marks are that I’m seeing on the 360 when these marks are out a ways from the boat? I want to cast to them and not vertically fish them.

Also, the large marks/fish I’m seeing in open water seem to come and go with each sweep of the transducer. What is the story with that? Is the orientation of the fish important to how well the fish shows up? Are they turning away from the transducer perhaps, weakening the signal return?

Any help with how I’m trying to use the unit in open water is appreciated!

[Wayne P.]

Side Imaging is slant range (360 is Side Imaging). Recorded subjects are at the distance from the transducer in a straight line.

Just like Side Imaging, the recorded subjects with the most recent history are against the scan line (very top row if screen pixels on the SI view). Until the next side of the scan line passes over a subject, all recorded between the two halves of the scan line is history.



On the bottom half of the scan line, the right side is the most recent data, the left side is the oldest data. On the top of half of the scan line, the left side is the most recent data and the right side is the oldest data. Scanning is clockwise.
A particular direction is rescanned twice per 360 revolution.

If a subject is close enough to the bottom, it will have a shadow on the bottom within the scan range. That is the only way to judge elevation above the bottom.

The two fish on the left side in the water column (black area) at 270 degrees and about 25' from the transducer have their shadows just on the other side of the 30' range line. Since the fish and their shadows are not touching each other, that indicates they are not on/near the bottom. That is about all you can tell with SI/360.



If a fish moves or you move during a scan rotation, it won't be recorded in the same place as before. If it is not re-recorded, it is not within the coverage of the 360.

[Wayne P.]

This will give you a better relationship of fish to shadow since the fish are not in the black water column.
You can see there is some separation between them and their shadows indicating they are 3'-4' above the bottom. Note the range setting and depth as a reference to distance/size.

[brianf.]

Wayne, this has been very instructive and helpful. Thank you!

[BassCatKev]

This question of Brian's is what I was trying to think how to ask.

If I'm drifting in the middle of a lake that is 80ft or more deep for a long way in any direction looking for stripers (or whatever fish) in open water and have full circle 360 on the screen with say range of 70 and see a fish appear. At least it shows me what direction to fire a cast. But there is no way to know what DEPTH in the water column that fish is.

Wayne what do you think the limit is on how high a fish can be in the water column and still show a shadow on the bottom? I'm assuming I'm never going to be able to see the shadow of a striper that is 20 feet below the surface over 80 feet of water even if I had my range set way high. But maybe I'm wrong. There is no telling what type of image you may show to prove me wrong

Loved the examples you posted above.

[Wallace]

Something else to think about. Right about now when I’m fishing more open water and less structure . You can speed up the rotation of the 360 to stay a little more on top of the bait . fish get harder to see but Its pretty obvious what’s going on when you see an explosion on the screen where the fish are tearing up the bait. Time with it is the biggest teacher.

[Wayne P.]

This question of Brian's is what I was trying to think how to ask.

If I'm drifting in the middle of a lake that is 80ft or more deep for a long way in any direction looking for stripers (or whatever fish) in open water and have full circle 360 on the screen with say range of 70 and see a fish appear. At least it shows me what direction to fire a cast. But there is no way to know what DEPTH in the water column that fish is.

Wayne what do you think the limit is on how high a fish can be in the water column and still show a shadow on the bottom? I'm assuming I'm never going to be able to see the shadow of a striper that is 20 feet below the surface over 80 feet of water even if I had my range set way high. But maybe I'm wrong. There is no telling what type of image you may show to prove me wrong

Loved the examples you posted above.

The second screen shot in post #2 shows the fish on the right side at the 10' range line and their shadows at the 40' range line. The depth is just 16' so you would have to extrapolate what angle would show fish shadows on the bottom at a depth of 70'. Then you would need a 360 Range setting that will have some bottom displayed. I would guess the chance of seeing fish shadows at that depth and range would be near zero.

[BassCatKev]

Thanks Wayne. I get it.