I use side scan sonar a lot and I see a lot of piccies like this.  Some have
obviously been faked up but as you say Matthias, there seems to be an impact
on the floor.  I have had a good look and my judgement is lets kit up and go
and take a look.   If it isn't there we have a good dive and get to play
with our toys which is what it's all about.

Steve

the plane could have shifted wouldn't take much with that surface
area, but it could also be scour marks from current

not enough information on a low res image, especially since it's
missing the rest of the display which would indicate distance of the
fish from bottom and distance from the surface, dist to object and you
can then figure out approx size of the object and height above the
bottom (from shadow)

the acoustic shadow is a mite strange ... but that doesn't mean it's
fake

the starboard wing has shadow on both leading and trailing edge
I'm trying to figure out where the fish would have to be placed to
create that shadow, AND keep in mind the rest of the shadows.
Acoustic shadows are perpendicular to the transducer face and should
be consistent in regards to orientation

note: a depression will display a shadow , current can create
turbulence at an object and dig a depression in front of the object,
which will create an acoustic shadow,  though the shadow seems to be
too even .. it's not what I would expect, but image interpretation is
as much voodoo as science :^)

image id and date are mucked with in the upper left hand corner
I get 24/12/0(?) looks like a 03 the text before is ? seems to be WTCH
... (?)

I could be a sidescan image from a long range unit (freq 100 khz or
less)  with the fish held high and the target is at the far edge of
the field ...  it does look like there was some image manipulation to
degrade the image, and the obscuring of the id tag

or it could be a plane in a field next to a fence and a healthy dose
of photoshop

    my 2 cents = no answers, just more questions :^)

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