SI and DI Sensitivity

[Doug Vahrenberg]

Here is example how adjusting the Sensitivity settings to the conditions will improve displaying the data so you can see it easier. There is no one setting for all situations but understanding how to adjust and when will make it easier. Balance between hard and soft returns is the key. Too strong and use lose details, too low and you lose details. Soft bottoms typically require a little more sensitivity and hard bottom require less to get good balance.

From Low to High in steps of 4...













8 to 12 is may favorite starting point for most situation as you can see above are really starting to balance. 10 is Factory Defaults like this image below.



Down Imaging usually requires a little more sensitivity about 1 or 2 notches up from SI. Here are a couple examples of to low and too high settings and one I feel is balanced correctly

Too Low...



Too Hot...



Just Right...see the details in bottom and structure and fish better???

[91reddog]

Doug,

I know you dont care for auto. Care to explain?

Wouldve been nice to have an auto shot in the above series of pictures for comparisons.

I use auto almost exclusively when using 455. 800 , not so much

[T Mike]

Great post Doug. Also depth and beam width (SI) has an effect on sensitivity as well. Great illustration of how to set up your unit.

[Doug Vahrenberg]

I have found that AUTO can be overpowering and hide details that I'm looking at. I highly do not recommend. I've played with it and it hides alot of fish. Balancing is the key to finding fish especially on very hard bottoms. I've run sensitivity to 2 in real shallow solid rock lakes to get the balance needed to be able to see the fish versus the hard returns. Cool part is you can freeze the screen and adjust sensitivity to learn more about your image and what level you need to run when your in that type of structure. This is probably the second most biggest concern I see with images...to much sensitivity and hiding details...Chart Speed is first.

[longbeard]

Sorry for the stupid question but I'm trying to figure out how to use mine. In the first set of pictures are all of those white dashes on the left fish?

[Doug Vahrenberg]

Yes they are...THere was probably 50 boats catching crappie in this channel. Not very big ones but everyone was catching fish.

[longbeard]

So all of those are crappie on the left and lower right? I see them in the water column, just trying to get a handle on it. Thanks

[Doug Vahrenberg]

See all the bright white dots on the left side on this mud bottom? Those are Crappie too.



There are thousands and thousands of Crppie packed into this cove and scattered everywhere.

[liljp1514]

Those DI shots just blew my mind. I have SI/DI but just seeing the adjustments to sensitivity you just made makes me wonder just how much I've missed because I kept the sensitivity too low.

From the pictures you've shown, for new guys, would you recommend turning sensitivity high and adjust down so you don't miss things like the trees in pic 1???

[Doug Vahrenberg]

I would start about 2 numbers higher than you run SI. If running SI at 10 run DI at 12. You can always freeze the frame and find the best spot for you by adjusting sensitivity up/down.

[T Mike]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by liljp1514 &raquo;</td></tr><tr><td class="quote">Those DI shots just blew my mind. I have SI/DI but just seeing the adjustments to sensitivity you just made makes me wonder just how much I've missed because I kept the sensitivity too low.

From the pictures you've shown, for new guys, would you recommend turning sensitivity high and adjust down so you don't miss things like the trees in pic 1???

</td></tr></table>

To me that is the #1 mistake people make when tuning a unit. Not enough sensitivity or too much. It would blow your mind what you are missing especially on sonar.