yes, i use the towfish with 60 m cable.
at 2 or 3 m i take 5 depht under transducer range (15 m)in 800 khz, and at 3 or 4 meter 10 depht in 455 khz (30 or 40 m range). Picture under 3 meter in 455 seen over exposed
now i begin to make another towfish in composite (carbon and epoxy fiber)
next satuday i want to dive on another point find with the sonar.
i think there's an anciant wreeck ...
there's no visibility for foto, just 1 meter max.
it's the adventure !!!