Topic: ALL SI Models - depth controll on si

[sjefsrafsern]

Model:	ALL SI Models
Suggested Upgrade:	depth controll on si
Explanation:	i think it would be nice to be able to set max depth to 10 feet 20 feet 30 feet etc when running side imaging and still see 90 or 150 feet to the sides. this would make the unit extremely good for trolling. as you can see how big sinkers etc you would need to reach down to the fish youre supposed to catch with the planerboard lines.
Added in Software Version:
Comments on Update:

[Humminbird_Greg]

You should already be able to set the Max depth menu at 10, 20, 30 feet or whatever you want.  It does not affect the range that the SI sonar works to (the Si Range menu does that).

[sjefsrafsern]

yes but only in 2d and di, the max depth menu doesent change what i can see on my side imaging screen. if i set max depth to 15 feet i still see bottom down to 90 feet if my si range is set to that.

[Humminbird_Greg]

So what is it that you are wanting?
I guess I am missing what it is you are asking for… 

[sjefsrafsern]

ill try again. si range as it is now cotrols both how wide my wiew is and how deep my image is.     ( 90 feet wide is also 90 feet deep.) id like to have the opportunity to choose to see only the top 10, 20 or 30 feet. when i got my side range set to for example 90 or 150 feet. this way i can set to different depths in si wiew and figure out how deep the fish at 70, 80 or 90 feet of to the sides are.

[Humminbird_Greg]

Okay, I understand now.  I suspected that this is what you wanted but had to be sure.

My opinion:
With the current design of our Side Imaging units this is not possible.  With the single Si sonar beams used for each side there is no way to determine whether a sonar return is from 50 feet to the side, directly under the boat or on an arc somewhere in between those.  What would be needed to do what you want is a multi-beam array of elements inside of a transducer.  This would be mega-expensive!

[sjefsrafsern]

okay, i kind of thougth so.  but worth a question. but maybe you could tell me the angle between top of the 800 khz beam and surface? then i could calculate how much of the upper water column i lose at 70 80 or 90 feet to the side and maybe narrow down my search a little bit. (if i switch between them (455 and 800) and see if the fish stays on screen or dissapear, as i pass by them on several runs)

[Humminbird_Greg]

Not really.  The beam width is affected by many factors that are beyond our and your control.  I can tell you that we spec the 800 Si beam to cover 130 under the boat.  So the angle from the surface that is not covered would be 25 degrees (180 degrees minus 130 degrees covered by the transducer, divide this by 2 as there are two sides involved).

[sjefsrafsern]

Ok, thanks for answering my questions. And giving me a little insight in how these things work.
Stig