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Moose1am
01-18-2005, 02:19 PM
Thanks to Larry-Southern IN I went to the BnM web site and read the news storys there. The first one caught my attention not because of the pretty young lady ( well that too LOL) but because of the gist of the story. What the author failed to realize was that he at first was fishing way too deep. Why? Well his depth finder told him the fish were 10Ft away from the transducer. But he Misunderstood what his depth finder was telling him. He thought the fish were 10ft deep or 10ft below the surface. Actually he was dead wrong! Why was he wrong? Well 10ft away does not mean 10ft deep. This is a CRITICAL MISTAKE that I often have made. I forget how the depth finder works and if I had not gone back and read an 1976 article about how depth sounders work I would have missed this key point again. Hopefully when I am out on the water I will remember this key point. Time for another graphic here. Will be right back to finish this story and show you why he didn't catch fish right away. In the mean time here is the web site where the article is found. Read it first and then read the rest of my post after I come back and add to this initial post.

http://www.bnmpoles.com/newsletter/011705/011705.html


Try not to drool over his cute daughter ! LOL


ok here is the image that I promised that shows what I am trying to get across here.

Remember that the actual cone of sound does not quite look like my crude drawing. I will try to post a more accurate diagram of what the cone of sound should look like in 2 dimentions. Remember that the cone of sound influnence is actually 3 dimentional and varys with the amount of power output. You increase the senitivity on your depth sounder and the cone will increase in size. You decrease the sensitivity and the cone angle will decrease. All other things being equal.

Barnacle Bill
01-18-2005, 02:57 PM
I gotta disagree with that one. A fish 4 foot deep is going to be in the field of view for approx 1.3 ft. That is with a standard 20 degree transducer. There is no way it could measure 10 ft away even at the edge of the cone. Now with some of these new fangled super wide, multi-transducer setups, I could see where that might apply. I definately go along with the fast trolling this time of the year. I've been doing that for years and it does work.

Moose1am
01-18-2005, 03:08 PM
OK I admit that I over did the dimensions but the principle still works. Would you catch the same fish if he were only 8ft deep and you fished 10ft deep? See my point now?

Let me change the graphic and then maybe it will make sense

Also you bring up another variable with transducers. Wide angle cones. There are some transducers that shoot sound waves out to 45 deg on either side of the boat. So in deeper water these wide angle tranducers are showing fish that are out to the side of the boat.



I gotta disagree with that one. A fish 4 foot deep is going to be in the field of view for approx 1.3 ft. That is with a standard 20 degree transducer. There is no way it could measure 10 ft away even at the edge of the cone. Now with some of these new fangled super wide, multi-transducer setups, I could see where that might apply. I definately go along with the fast trolling this time of the year. I've been doing that for years and it does work.

PanMan_VA
01-18-2005, 03:28 PM
It takes a transducer angle of 133 degrees for the math to work out. That would be one huge fish arch!

Moose1am
01-18-2005, 03:29 PM
The fast trolling is what surprised me. I should know by now that life if full of surprises and variations. LOL

I have very limited experience in winter fishing but I have had some. Last year I was able to find some suspended crappie out in the middle of a lake and actually caught them using slow vertical jigging. But that day it got up to 50 deg F and it was nice and sunny when I went fishing.

I think that one thing we should remember that as the sun changes position and the winds pick up or lessen or even change direction that the fish respond quickly to these changes.

In the KY Lake Crappie Study that was written about in the Feb Issue of In-Fishermen Magazine the author of the study described how one crappie traveled over 4miles in one 24 hour period. The other crappie that he tracked for 24 hours that one day didn't move hardly at all. So not only do we have the varabiles of the weather but we have fish with different attitudes and behaviours.

I think the main point in the article was that he needed to fish shallower. Remember that by going faster the lures actually will rise up and be in shallower water. Maybe slow and shallow would work well too.

He didn't tell us the water temps in the article and if they were rising or falling or did he?


I gotta disagree with that one. A fish 4 foot deep is going to be in the field of view for approx 1.3 ft. That is with a standard 20 degree transducer. There is no way it could measure 10 ft away even at the edge of the cone. Now with some of these new fangled super wide, multi-transducer setups, I could see where that might apply. I definately go along with the fast trolling this time of the year. I've been doing that for years and it does work.

Moose1am
01-18-2005, 03:34 PM
If you did the math with 4ft and 10ft then please recalculate with the new measurements. I can refine the numbers to make the cone angle 45 deg. if necessary. Also is a 20 deg cone angle the angle between the middle of the cone and the outer edge or from one edge to the other edge of the cone?

Can you redo the math again. Use 8ft and 10ft this time and tell me the angle of the dangle. I hated Trig. Sin Cos Tan Rads Grads and Radians LOL



It takes a transducer angle of 133 degrees for the math to work out. That would be one huge fish arch!

Moose1am
01-18-2005, 03:39 PM
Finally someone got it. Thanks Tool. I hope it works. I know that I am going to try to remember this.

Another thing that I take into consideration is how deep my tranducer sits in the water. My old depth sounder will not compensate for the two feet depth of my transducer which I moutned on the bottom of my trolling motor. So I have to do the math in my head. Fish on my depth sound that show up at 8ft deep are acually only 8ft away from my transducer because my transducer is already 2ft deep when it starts. So a fish's depth is hard to determine.

Best thing to do is vary the depth a few feet on either side of what the depth finder says. Like bracketing the exposure setting on a camera.



Early this winter I was on Wylie trolling during the day with pete up north above the buster boyd bridge and we weren't catching squat. I sped the trolling motor up from .3-.5mph to .8-1.2 mph on the gps and we caught several crappies and a good sized green carp on our 1/16 oz jigs. I think we were fishing them too deep because of our slower speeds. I can't wait to get out and give this method a try.

Barnacle Bill
01-18-2005, 04:56 PM
Hey Moose, the cone angle is edge to edge. I forget all that math stuff. I used to have to do oblique rectification with aerial photography way back in my Navy days. That is one of those things that if you don't work just about daily with, you forget. And believe me, My forgetter works real good today. LOL

I've read in several places that a rule of the thumb for 20 deg transducers is the area of coverage is about 1/3 the depth. So in 30 ft of water, you are seeing about 10 ft of the bottom. A lot of the newer sonars you can compensate for the depth of the transducer (in programming) so you get an accurate reading.

Back to the fast trolling. We discovered that by accident many years ago. We were fishing one of the local rivers and not doing much. So we decided to try some place else and rather than taking in all 16 poles I just cranked up the trolling motor. Lo and behold, I went across the mouth of a creek and we caught fish. You get the idea. Anyway, at the time I figured they were just feeding shallow and I needed to adjust my bobbers. That didn't work. They wanted a fast moving, shallow bait. Since then, we vary our trolling speed until we find what they want that day, or rather that hour because it can change in a heartbeat. Like Tool, our speed may vary anywhere from .5 to 1.5 mph.

PanMan_VA
01-18-2005, 05:14 PM
If you did the math with 4ft and 10ft then please recalculate with the new measurements. I can refine the numbers to make the cone angle 45 deg. if necessary. Also is a 20 deg cone angle the angle between the middle of the cone and the outer edge or from one edge to the other edge of the cone?

Can you redo the math again. Use 8ft and 10ft this time and tell me the angle of the dangle. I hated Trig. Sin Cos Tan Rads Grads and Radians LOL
74 degrees with the revised dimensions. The angle is measured for the entire cone, but calculations use half the cone angle in order to get a right triangle. From there, its a simple cosine function for depth or a sine function for distance from the transducer. I've seen arches like these when using my 50 KHz transducer.

Your other point about trolling is right on.

blufloyd
01-18-2005, 07:56 PM
Let's not forget that crappie feed upward. My only flasher is the vex in winter so speed trolling is kind of limited to about 5 inches at most. Point is a local fave lake the guys see the fish sitting on bottom in 7-11 feet of water. Rookies drop the jigs right down there amongst them and catch a few. Old pros like myself fish 2-5 feet down and let the hungery ones come up and nail it. Now on open water, I rarely have success in the depths people like to post and write articles about but I know I am doing it wrong with the wrong equipment and lures so limiting out doesn't hurt that bad.

Cane Pole
01-18-2005, 08:11 PM
Fish are here:

fish= sin (divided by) hypotenuse...that is ping!!!!

Larry-Southern Indiana
01-21-2005, 05:52 AM
I fish from 15' to 35' all the time. No one else is fishing as deep as me so their all mine :D :D

The amount of time I spend in shallow water each year ain't much. To fish shallow I like the lake above summer pool with water temp at 60 or above. Then I'll fish shallow. 3' and deeper then. That BnM rod I got will get a shallow water workout this spring. Then after spring it'll get a deep water workout rest of the year. I don't know about you guys but I like fishing deeper and away from standing timber. It's those humps with cover, outside bends with cover, flats with cover that I like the best. It there's no viseable cover for anyone to see I like that even better. If you could ride around Patoka some time you'll see 99.9% of the crappie fisherman sitting in the trees. Not me though I like deeper cover :D cause it's all mine.


Larry

PIGINTHEPIGPEN
01-21-2005, 10:21 AM
Moose are you useing a 1976 depth finder?

lovetofish
01-21-2005, 11:34 AM
Larry, I like to fish deep also. Down here in Louisiana, I see so many people fishing the structure they can see. I like you-try to fish what no one esle can see. Two weekends ago I fished a little local crappie tournament and everyone was fishing structure they could see. I backed off and let them have it. I fished in 12 - 18 ft. water most of the day. Early I caught most of my fish about 6-8 inches off the bottom. As the morning went on I moved around following the shad. When the shad came up I shallowed up and caught fish suspended just under them in about 4 - 5 ft. I tried to stay away from everyone and still stay over the cover that was on the ledges and drop offs. I ended up winning the tournament with 10 fish coming in at 14.69 Lbs. The closest competitor had a little over 11 lbs. Some of the guys got to questioning my tactics. Some of the fellows I normally fish with just gave a little chuckle. They know I don't fish like most conventional fisherman. I'll try just about anything to catch a fish. Other little note is that in our tournaments you are only allowed to fish one pole at a time. Makes for a interesting day. Alot of changing going on at times. Eveyone talking about depth finders. I little trick a found a long time ago(some others may have tried it too) is when you catch a crappie take him and tie a piece of monofilment in his lip and use enough to go back to the approx. depth or a little shallower with a balloon on the end. Most times that fish will go back to the school or area he was end. Makes for a good marker to fish around.

A BAD DAY FISHING IS BETTER THAN A GOOD DAY AT WORK

papasage
01-21-2005, 01:10 PM
that was a verry interested moos . i have one of the color selector . now i might understand why i dednt catch anything on the color that it showed .
the last issue of crappie has a add on a new and improved modle of the color combo celector . the co is in a little town 60 miles west of savannah . Broklett Ga.

there is a small crappie jig maker there . have seen a add on that buisnes in crappie magazine to.dont know if they are the same or related .
i have a brother that lives in that town . might give hem a call or e mail him and see if he knows anything about it . papasage

ncnat
01-21-2005, 04:32 PM
In that article, they mentioned the Color Selector and that it is no longer available (explains why I havn't seen one in years). Well it's available now at Bass Pro for $89. I guess I'll have to go get one now.


Thanks to Larry-Southern IN I went to the BnM web site and read the news storys there. The first one caught my attention not because of the pretty young lady ( well that too LOL) but because of the gist of the story. What the author failed to realize was that he at first was fishing way too deep. Why? Well his depth finder told him the fish were 10Ft away from the transducer. But he Misunderstood what his depth finder was telling him. He thought the fish were 10ft deep or 10ft below the surface. Actually he was dead wrong! Why was he wrong? Well 10ft away does not mean 10ft deep. This is a CRITICAL MISTAKE that I often have made. I forget how the depth finder works and if I had not gone back and read an 1976 article about how depth sounders work I would have missed this key point again. Hopefully when I am out on the water I will remember this key point. Time for another graphic here. Will be right back to finish this story and show you why he didn't catch fish right away. In the mean time here is the web site where the article is found. Read it first and then read the rest of my post after I come back and add to this initial post.

http://www.bnmpoles.com/newsletter/011705/011705.html


Try not to drool over his cute daughter ! LOL


ok here is the image that I promised that shows what I am trying to get across here.

Remember that the actual cone of sound does not quite look like my crude drawing. I will try to post a more accurate diagram of what the cone of sound should look like in 2 dimentions. Remember that the cone of sound influnence is actually 3 dimentional and varys with the amount of power output. You increase the senitivity on your depth sounder and the cone will increase in size. You decrease the sensitivity and the cone angle will decrease. All other things being equal.