The 2lb ‘Tennis Ball’.
I recently heard that a tennis ball tied to a weight and dropped in the water (don’t forget the marker buoy), will appear as a 2lb (approx.) fish on your sonar when driven over directly above.
This experiment requires the following items:- a tennis ball, some cable ties, a carabiner clip, a thin rope and a marker buoy. Tie loops in the rope at 1ft from weight and then every meter thereafter.
My first spot was in 36ft of water with the tennis ball clipped on the 1ft loop, this was to represent a fish sitting 1ft off the bottom. I drove over it several times (more like a dozen times) on auto depth and never even saw it, on both Humminbird 997 and Lowrance LCX37c.
Then I slowed my speed down and used a depth range of 20-40ft on my Lowrance, and there it was, exactly 1ft off the bottom with perfect target separation. This image has 600 vertical pixels representing 20ft of water. Even some of the loops tied in the rope were visible
Then I tried it with the Humminbird with the QuadraBeam transducer, and depth range set from 25 – 40ft. Here too it became visible, and the loops, but the target separation seemed very poor at first. I did not think to change my view to single 200kHz (480VP) and therefore this image only had 240 vertical pixels to display 15ft of water.
My next experiment was unclipping the ball and moving it to the 1 meter loop (3ft off the bottom) and moving to a depth of 40ft.
On my first pass with the Lowrance I could see the ‘2 pounder’ on full auto depth range.
The second pass was with the depth range set to 34 to 42ft. This is using the full 600 VP for only 8ft of water. The first thing to notice is the incredible accuracy and target separation, even the 1ft loop in the rope can be separated from the bottom and weight.
Then it was time to put the Humminbird 997 to the test. My depth range was set from 30 to 45ft therefore only giving 240 VP to represent 15ft of water. Even at this extremely low VP it was able to see the weight on the bottom, the 1ft loop (loop and weight fused), the ‘2 pounder’ (even the FishId picked it up as a fish at 37ft – exactly the right depth) and finally 2 other loops in the rope on the way up.
Continued at Albert Falls Dam KZN.
After a bit of a rocky start with the HDS8, due to several influencing factors being corrected, I got some great results to follow up on.
This exercise was done at Albert Falls on the 12[sup]th[/sup] July 2009 when the dam was at 95% (5ft down from full).
I dropped the marker in 25ft of water with the tennis ball suspended at around 22ft, 1 meter (3ft) off the bottom. Nearby were 2 brush piles, one large one of around 10-13ft high in 30ft of water (wpt 8), and another of around 7ft high in 40ft of water (wpt 9).
This first shot was with the Lowrance LCX 37c going from the shallows towards wpt9 in the deeper water. The settings used for this was at 200kHz , Ice View with the sensitivity at 100%, colour line at 80% and a range of 10 to 45ft. The ball can be seen suspended off the bottom as well as the knots in the line.
The next shot was with the HDS8 going from the shallows towards the smaller brush pile in the deeper water. The settings used was 83kHz, Palette 12 (old ice view), sensitivity Auto +23%, Colourline 50%, and a range of 10 to 45ft. There seems to be more clutter on the screen, but keep in mind that this was done at 83kHz, and the knots (arches) in the line are very clear.
On one of the passes over the big brushpile, it was quite interesting to see this fish swim out of the brushpile.
Another very powerful feature of the HDS technology is target separation of fish holding very close to the bottom. As can be seen in this shot with the tennis ball only 1ft off the bottom, in 26.5ft of water.
Then I tried the Humminbird 997 with the Quadra Beam transducer on 83kHz going from the deeper 40ft water, to the tennis ball in 23ft. Sensitivity was set to 19 using the standard palette. I found this units representation of what was in the water very good, even with a fish hanging around the second brushpile in 35ft of water as a bonus. I also liked the way the system makes a very clear differentiation of the knots in the line, and the actual tennis ball. Once again proving the effectiveness of the Humminbird’s advanced FishID feature.
I also found these larger predators (I presume) feeding on bait fish at Alberts using the Lowrance HDS8. I must have gone over them 5 or six times and they were still there. But when I went over it with the Humminbird only the larger fish showed up well. Unfortunately I didn’t save a screenshot of the Humminbird to show the difference.
The other thing is that the fish soon disappeared while pinging them with 1000 watts of RMS power, (8000w peak to peak) with the Humminbird. But with the HDS8 they seemed undisturbed by our mere 31 watts of the Broadband technology.
I also tried the green and black night view palette on this baitball, the results were quite good I think.
I recently heard that a tennis ball tied to a weight and dropped in the water (don’t forget the marker buoy), will appear as a 2lb (approx.) fish on your sonar when driven over directly above.
This experiment requires the following items:- a tennis ball, some cable ties, a carabiner clip, a thin rope and a marker buoy. Tie loops in the rope at 1ft from weight and then every meter thereafter.
My first spot was in 36ft of water with the tennis ball clipped on the 1ft loop, this was to represent a fish sitting 1ft off the bottom. I drove over it several times (more like a dozen times) on auto depth and never even saw it, on both Humminbird 997 and Lowrance LCX37c.
Then I slowed my speed down and used a depth range of 20-40ft on my Lowrance, and there it was, exactly 1ft off the bottom with perfect target separation. This image has 600 vertical pixels representing 20ft of water. Even some of the loops tied in the rope were visible
Then I tried it with the Humminbird with the QuadraBeam transducer, and depth range set from 25 – 40ft. Here too it became visible, and the loops, but the target separation seemed very poor at first. I did not think to change my view to single 200kHz (480VP) and therefore this image only had 240 vertical pixels to display 15ft of water.
My next experiment was unclipping the ball and moving it to the 1 meter loop (3ft off the bottom) and moving to a depth of 40ft.
On my first pass with the Lowrance I could see the ‘2 pounder’ on full auto depth range.
The second pass was with the depth range set to 34 to 42ft. This is using the full 600 VP for only 8ft of water. The first thing to notice is the incredible accuracy and target separation, even the 1ft loop in the rope can be separated from the bottom and weight.
Then it was time to put the Humminbird 997 to the test. My depth range was set from 30 to 45ft therefore only giving 240 VP to represent 15ft of water. Even at this extremely low VP it was able to see the weight on the bottom, the 1ft loop (loop and weight fused), the ‘2 pounder’ (even the FishId picked it up as a fish at 37ft – exactly the right depth) and finally 2 other loops in the rope on the way up.
Continued at Albert Falls Dam KZN.
After a bit of a rocky start with the HDS8, due to several influencing factors being corrected, I got some great results to follow up on.
This exercise was done at Albert Falls on the 12[sup]th[/sup] July 2009 when the dam was at 95% (5ft down from full).
I dropped the marker in 25ft of water with the tennis ball suspended at around 22ft, 1 meter (3ft) off the bottom. Nearby were 2 brush piles, one large one of around 10-13ft high in 30ft of water (wpt 8), and another of around 7ft high in 40ft of water (wpt 9).
This first shot was with the Lowrance LCX 37c going from the shallows towards wpt9 in the deeper water. The settings used for this was at 200kHz , Ice View with the sensitivity at 100%, colour line at 80% and a range of 10 to 45ft. The ball can be seen suspended off the bottom as well as the knots in the line.
The next shot was with the HDS8 going from the shallows towards the smaller brush pile in the deeper water. The settings used was 83kHz, Palette 12 (old ice view), sensitivity Auto +23%, Colourline 50%, and a range of 10 to 45ft. There seems to be more clutter on the screen, but keep in mind that this was done at 83kHz, and the knots (arches) in the line are very clear.
On one of the passes over the big brushpile, it was quite interesting to see this fish swim out of the brushpile.
Another very powerful feature of the HDS technology is target separation of fish holding very close to the bottom. As can be seen in this shot with the tennis ball only 1ft off the bottom, in 26.5ft of water.
Then I tried the Humminbird 997 with the Quadra Beam transducer on 83kHz going from the deeper 40ft water, to the tennis ball in 23ft. Sensitivity was set to 19 using the standard palette. I found this units representation of what was in the water very good, even with a fish hanging around the second brushpile in 35ft of water as a bonus. I also liked the way the system makes a very clear differentiation of the knots in the line, and the actual tennis ball. Once again proving the effectiveness of the Humminbird’s advanced FishID feature.
I also found these larger predators (I presume) feeding on bait fish at Alberts using the Lowrance HDS8. I must have gone over them 5 or six times and they were still there. But when I went over it with the Humminbird only the larger fish showed up well. Unfortunately I didn’t save a screenshot of the Humminbird to show the difference.
The other thing is that the fish soon disappeared while pinging them with 1000 watts of RMS power, (8000w peak to peak) with the Humminbird. But with the HDS8 they seemed undisturbed by our mere 31 watts of the Broadband technology.
I also tried the green and black night view palette on this baitball, the results were quite good I think.