Sonar quiz #8

[rnvinc]

Below are 3 screenshots of the very same brushpile...(I froze the screen scroll and captured all 3 screenshots 1 after the other)..

Each screenshot shows the cursor position in a different spot on the display...

Which cursor position would make the most accurate waypoint in relation to the actual brush pile...??

And explain why...
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Screenshot 1...:



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Screenshot 2...:



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Screenshot 3...:



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Rickie

[toofuss]

I'm gonna say #2 because its the highest thickest part of the pile

[Redge]

I am going to say #1 because it seems to work for me. I think ! Looking forward to the real answer with an explanation. Always up to learn something new!!

[kosmo]

All of the above

[Redge]

My reason is, because that is where the brush pile actually is on the lakebed. I find it interesting to mark three places when I find something new. I mark one in SI and normally one or two on the DI screen. It is amazing to see how far apart they can be, on the map!

[Don G]

#1...

[CrappiePappy]

All of the above

I'm with you, Koz .... seems like the cursor is in exactly the same position (vertically, in relation to the screen), just in three different parts of the water column ... which the GPS isn't reading, anyway, as it's reading where the antenna is. Shouldn't matter where the cursor is (water column depth) for a 2d screen ... since the "brushpile" showing on the screen is locked onto by the GPS antenna, and all three cursor positions are in exact vertical alignment ... so it would seem like the GPS coordinates would be exactly the same.

... cp

[rnvinc]

Someone try it for yourself...and then come back here with your results...

And then we will discuss why this result happens like this...

Rickie

[brettw]

Guessing no.1
Bottom of pile is best as top may be leaning, for instance , a tree,

[GroutScout]

I think I will guess #1 since they all show different distances from the transducer I'm guessing the bottom of the pile would be closest to the pile; but then I might be wrong and it might be the mark at the top of the water column. I'm interested in the answer and I hope you really know the answer and aren't just making it up.