Sonar 102 - Arches and other things

[@weFishAU]

Other episodes in this series: 2D Sonar 101: kzbin.info/www/bejne/jJO9ipimjKuYqrc Arches and other things: kzbin.info/www/bejne/maPGmIyJrKZ_epY Bottom Hardness and Speed: kzbin.info/www/bejne/gqfHfahseZ2ehKs Final 2D Sonar Insights: kzbin.info/www/bejne/jl6Qn62YiNqIeas Down Vision Sonar Basics: kzbin.info/www/bejne/qHyTq5SBmpyFapY

[@axelohmen4138]

Thank you for producing these videos. I note you said i hope im not boring you with to much detail. I cant believe how quick that 20min episode went, it felt like 5 minutes. Thank you its helping me immensely, tight lines buddy.

[@weFishAU]

Glad you like them! I'm happy to answer any questions as best as I can.

[@seastrength1291]

Again, very helpful information for a better understanding of sonar technology. Enjoying the series.

[@weFishAU]

Thank you, I'm glad you're finding it helpful.

[@constable49]

I have been using sounders since they were invented, they have come a long way. I have a very good understanding of how they work but I am enjoying how you break it down because it reinforces what I do know and reminds me of what I may have forgotten. I am enjoying this series thank you.

[@weFishAU]

Thank you. Always good to get feedback.

[@duffusedward1326]

The best fishing video! Thanks!

[@weFishAU]

Thank you. Glad you enjoyed it!

[@duffusedward1326]

@weFishAU Great works!Looking forward to your future episode on 3D sonar.

[@deefa_damo]

Very helpful - tying all the bits of info together into a easy to understand story - many thanks for sharing. I'm about to go and check out my sounders settings a bit more.

[@weFishAU]

Glad it was helpful! Definately worth the effort to spend some time just playing with the settings.

[@moodybloke74]

Thanks for these videos.. They are a tremendous help.

[@weFishAU]

You're welcome. Glad you like them!

[@surfinpinetree]

Good stuff. Look forward to your hard bottom and soft bottom. I have 3/d 200/50.

[@weFishAU]

Thank you. I should get that one up before the end of the month.

[@Camh1968]

@@weFishAU hi again. This link shows a good representation of the bottom coverage whilst underway. kzbin.info/www/bejne/gV7YZmqblMSGsLssi=ISpGKYHoevk9grte Ignoring the verbal commentary in this video, you will see undulating bottom structure being covered by the beam as the boat travels forward. This is the question I have - how do these 3D undulations get represented on the 2D sonar. I know you were going to make a follow up video to help explain this. I just thought this link helps to better articulate what I am trying to get across… Thank you Cameron

[@weFishAU]

I think I understand what you are asking. It is difficult to put into words other than to say that the undulations show as differences in the thickness of the red line depicting the ocean floor. Basically, the 2D representation hides everything below the highest point of the undulations. I will try to include some footage to illustrate exactly what I mean in the next sonar video.

[@Camh1968]

@ many thanks. I look forward to your next video. Interesting detail on the changing line thickness but Still hard for me to grasp. Thank you Cameron

[@Camh1968]

Hi. What parameters in the ping are used to generate the 2D Sonar image of bottom structure? How is this ping conversion made to what we see on the MFD? Cameron

[@weFishAU]

Wow. That is a complicated question. The time taken between sending the ping (sound wave) from the transducer until its return echo being recieved is divided by two (2 way trip) and then calculated against the speed of sound in water to get the depth. Since the speed of sound in water changes with temperature a more accurate reading will be obtained from a transducer that measures temperature. However, temperature changes with depth and temperature inversions can still introduce noise and errors. Another point. Since the ping that has been sent must be received before the next ping can be sent, pings in deeper water need to be less frequent because of the longer time taken to recieve the echo.

[@Camh1968]

@@weFishAU Thank you for this response. - Does Chirp technology also depend on receiving sent ping before sending the next ping? - Does every single ping sent down bounce off the very first obstruction it meets and not travel down any further? - Does the MFD continually display millions of pings by computing the nature of the ping and transforming it into a scrolling graphical form? I have trouble interpreting what I see on the MFD from a bottom structure profile point of view. I do understand the fish viewing aspect though and that most of what we see on the MFD is historical. Can you please further elaborate on what is seen on the 2D Sonar MFD from a bottom structure point of view as it continually changes from right to left and how it matches the ping action (in a 3D conical shape underneath) as you drive forward...? Cameron

[@weFishAU]

Chirp pings are across a band of frequencies. While it would be possible to have some overlap, I doubt that the benifit would be worth the effort. Think of every ping as starting as a dot at the transducer and then expanding as a circle all the way to the ocean floor. That is how the cone is formed. Each ping covers the whole area and will be reflected off everything it encounters. The time taken for the return and the amount of energy in the return determines the depth and colour of the pixel on the screen. The MDF only displays the current ping in the A-Scope. Everything to the left is a history of what was in the A-Scope in the past. I'll try to cover some more about the bottom structure in the next video.

[@Camh1968]

@@weFishAU Many thanks. Interesting points to soak in. These sound waves are quite amazing! I like your 'point to circle' definition of the sound wave moving within the water column.... Let me know when your next video on bottom structure is up. My brain just can't seem to crack this last piece of the puzzle (matching the moving 2D Sonar in front of me (helm) to the moving 3D cone underneath me). Knowing the science you have described does help connect a few pieces together though...

[@Camh1968]

@@weFishAU How can a single return ping provide sufficient data to show double bottoms on the A-Scope (and subsequently MFD historical trace)? Cameron