Topic: Down Imaging

[bobxxx]

In the sonar menu there is a down image setting for narrow,medium, and wide .Does wide go into the realm of side imaging?Is there a specific cone angle or what.
Thanks

[Humminbird_Greg]

It was my understanding that the Wide setting included all of the sonar data from both the Left and Right Si sonar beams.  Narrow was just what was common in both Si beams (where they overlap).

[bobxxx]

I take it that narrow beam would be mostly directly below the boat but  does the wide beam go out,say 30 ft. in 10 ft of water on both sides of boat?
Thanks, Greg

[kosmo]

this is di set to wide 800khz in 10 feet of water

[kosmo]

same tree that i got more strait over. 455zhz    di set to wide

[Rough House]

Man I wish my DI looked like that!!! Those are really nice pics.

[newkid4si]

bobxxx
   Here are the numbers that I have. I got them from Robert.
    DI stats @455kHz.

    DI--wide-- = 2.5x depth. ............20 FOW= 50' coverage ( SI return )
    DI--medium- = 1.5 depth............20FOW=  30' coverage ( 2D+ 30'SI )......... clearer image
    DI-- narrow-- = 1.25 depth..........20 FOW=  25' coverage ( 2D= 25' SI ).......most detail on bottom

            Mike

[short grub]

I think I saw on one of Doug Varenburgs (spelling ?) videos that narrow is like your 20 degree cone

medium coverage is same as depth, and wide is 1.5 X depth

hope this helps

[bobxxx]

That cleared everything  up.
Thanks guys

[rnvinc]

That cleared everything  up.
Thanks guys

Didn't clear it up in my simple mind...

Greg's numbers - do not equal Robert's numbers - do not equal Doug's numbers...

I feel the definitive answer is vague with only the original programmer knowing the "true" numbers...

Wide is wider than medium is wider than narrow...

Rickie

[kosmo]

Didn't clear it up in my simple mind...

Greg's numbers - do not equal Robert's numbers - do not equal Doug's numbers...

I feel the definitive answer is vague with only the original programmer knowing the "true" numbers...

Wide is wider than medium is wider than narrow...

Rickie

what about contrast? doesnt contrast  have to be figured into this? the reason that im asking is the higher the contrast setting the farther out from strait down you can see.the lower the contrast,the more detail strait under and less out farther ???

[short grub]

 guys I'm just going by what I've heard Doug V say on one of his video's

I would think that he has been told correctly, and I'm not trying to say that H Greg is wrong , because I think if anyone would know it would be Humminbird Greg.

Doug V is just the only source I had any info from

 

[sjefsrafsern]

hi, i have observed that my planerboards that i run 90 feet of to the sides appear in my di view both in wide and medium mode. i don not remember if it did in narrow but ill find out(and i think it did). but i really dont believe the di works as its supposed to do, and the we`re able to see only the things below our hull. (my di screen is usually set to display a depth like 100-120 feet, and the total depth where i fish can be upto 900 feet. so this might explain why this happens?)

regards stig

 

[Humminbird_Greg]

guys I'm just going by what I've heard Doug V say on one of his video's

I would think that he has been told correctly, and I'm not trying to say that H Greg is wrong , because I think if anyone would know it would be Humminbird Greg.

Doug V is just the only source I had any info from

Actually I think that DougV may have better information about this than I am – but I am trying to confirm this one way or another and get the “official” widths for each menu setting.

Contrast, Sensitivity menu settings along with how much sonar objects reflect can affect the ‘effective beam width’ as can any sort of filtering.  Remember that we are dealing with the information from two Si sonar beams here as well as the programming that merges that data into the Di sonar data.  There may not be any actual laboratory measured beam widths here.  What Doug posted mat be more from use.