I know that the cone on DI is wide(side to side) but narrow front to back. The question is how do you tell if what is displayed on screen is directly under you or off to one side?
Printable View
I know that the cone on DI is wide(side to side) but narrow front to back. The question is how do you tell if what is displayed on screen is directly under you or off to one side?
On a DI ... you pretty much don't. :Doh:Quote:
Originally Posted by Sovran
Best guess scenario is to know how wide a spread (angle) your DI beam is, according to whether you're using 455kHz or 800kHz, and understand that whatever is showing on your screen just went through the beam, somewhere.
800kHz = 45deg total angle .... @ 0.8 x water depth
455kHz = 75deg total angle .... @ 1.5 x water depth
I use 800kHz most all the time, and approximate that if I'm in 20ft of water ... then my DI beam is 16ft wide ... or 8ft wide to either side of the transducer. That's why I run 14' rods out in front of me, and shorter rods (8-10') out to the sides. That keeps most of my baits within the confines of the DI beam. I also know that whatever shows on the screen HAS TO be inside that beam, but I can only approximate its location within the width of it.
... cp :kewl
Thanks CP. I guess I was on the right track of tossing a weighted line out each side and dragging for the structure.
If your DI is on the TM, you can turn the motor 90 degrees if the object disappears you have it narrowed to 2 90 degree areas. If it stays visible on FF it is directly under TD.
Redge, go back to work. :biggrin
Also,u can use your 200khz (2d sonar)
If u have side imaging,u also could use that to reference the location
How would that help indicate which side of the tdx the cover object is on ??Quote:
Originally Posted by kosmo
... cp :kewl
I think what kosmo is saying is that would help you determine if the cover is under the boat. HB 2d sonar cone at 200khz is only 1/3 depth of water at the bottom or only a 6.67 ft circle in 20 feet of water (3.335' each side of transducer). So if you where using 2d/DI you would at least know the cover is under the transducer or to one side. Is your FF a SI unit or a DI only unit?
Your making my head work!Quote:
Originally Posted by rdjj71m
My unit is a Lowrance Elite 5 DSI (DI only) ... but, I don't miss the 2d imagery, even though that's all I've ever used (from the early 1970's until a few years ago, when I got the E5DSI).Quote:
Originally Posted by rdjj71m
It's bow mounted, as that's where I fish from ... and the 2d unit that's in the console (thru-hull mount tdx) is strictly for running the lakes, and for the rear seat angler to know the depth of approaching bottom & cover. It's a HB LCR.
... cp :kewl
OK that makes sense. My FF is a Lowrance Elite 4 Chirp(2d/DI) set up in my 14' yak. I have the transducer mounted in the front and I sit in the back. The idea being I see something on screen and by the time I come to a stop, I should be close with just 1-2 back strokes. I have been using a light weighted line to drag for structure on each side and if none found then fish straight down.
WHEN U SEE THE THICKEST AND HIGHEST SPOT ON UNIT U R RIGHT OVER IT.DROP JIG DOWN AND WATCH IT GO TO TOP OF BRUSH AND GET READY,NO NEED TO DRAG A BAIT AROUND
The new DI and SI are great, but work best when moving as a result of the thin beam. I still believe 2d has it's place. Just my $0.02
Agreed. We use 2d probably 90% of the time when trolling motor is in use.Quote:
Originally Posted by rdjj71m