DFF3d Settings for Black Marlin on the GBR

[BRD]

Hi Team,

I have a DFF3d setup with a TZ3/SX30 and B54 transducer in my boat, we fish out of Cairns on the GBR for Black Marlin. The system is sensational for Bathy mapping the inshore reef for bait and identifying safe anchorages, etc. When switching to Marlin fishing, we are operating in much deeper water from 150m/450ft out to 1500m/4500ft.

At these depths I am not interested in reading the bottom and obviously unable to bathy map, instead want to focus on searching the top 100m-200m of water, especially using the triple beam modes hopefully to identify individual fish/bait to the left or right of the boat.

I am interested in suggestions for the triple beam width and beam angle to give the best coverage in these top sections of water. Also suggestions on scroll speed at slow speeds (4 knots dead bait trolling) and any other specific settings that may suit (i.e. do I bother setting a manual depth and just zoom in the top section, etc etc).

Thanks in Advance for any help!

 

[Johnny Electron]

@Deep Blue

 

[Deep Blue]

BRD,

While there is no "Secret DFF3D Settings" to use when fishing for Tuna or Billfish, here are a few recommendations that may help you in the detection of pelagics within the 328-656 feet of the water column that you are intending to fish:

I’d adjust for a wide swath setting for the cross-section. I’d also use the Manual Settings and ensure that the TX Rate is set at “20”, and the TX Power is at “10”. Then I’d adjust the TVG to “0” or “1”, and then adjust the Clutter until you see some bait or the bait balls on the screen.

Here are the optimal settings that can be used for the DFF3D:

Gain - 50 to 72
Beam Angle - 40
Beam Width - 40
Picture Advance - 1/1 or 2/1
Clutter - 46
TVG - 5
TVG Distance - 300 feet (50 fathoms)

Keep in mind while the DFF3D has a beam width left to right of 120 degrees. However, the fore and aft beam width is 8 degrees. So, because these billfish are extremely fast, you are going to view them for a very quick second.

Happy hunting..!

- Deep Blue