HoW enviromental differences affect sonar images...(especially SI images)..

[rnvinc]

Here are 2 SI images with similar unit settings but giving stark image differences......

Differences that can only be attributed to enviromental differences in the 2 areas the images were taken..... Water depth/water clarity/bottom hardness....

Both images were taken:
1. Same 800 kHz beam setting
2. Same approximate boat speed
3. Same chart speed
4. Same "Contrast" setting 10
5. Same "Noise Filter" setting off
6. Very similar "SI Range" left and right

*One image very clearly shows the bottom all the way to the 90ft "SI Range"...hard bottom/clearer water gives better reflections for the sonar ping data to return to the unit...
*One image starts getting dark at 25-30ft out from the centerline...soft bottom/murkier water does not give as good of reflections for the sonar ping data to return to the unit...

It is my hope to shed some light on why some images just turn out better than others.....

Sometimes .....There are enviromental differences in the underwater world that just affect the sonar reflection echos differently....

Rickie