INTERPRETATION OF SIDE SCAN SONAR IMAGES

[different_stroks]

Hello all,

This is Ajay here and this is my first post.

Its nice to see a forum with some purpose and so much of knowledge.

I am an Engineer, just came across handling CMAX side scan sonar for first time.

I liked the system but i would like to know more about the interpretation of the images., without which the data has hardly any meaning .

I am looking to find some objects like anchors , pillars immersed in water . I need to know the dimensions of the objects too.

I can get some images but interpretation and dimensions calculations is getting tough.

I request you all if someone can help me with this.

Even some articles sent would benefit me.

Thank You all for your time.

Looking forward to exchange my knowledge with you all.

bye.

Ajay.

[Unregistered]

interpreting images

The best way to learn what the side scan is showing you is to practice with known objects. You must see the image on the side scan and know what it represents. all the systems are different with frequency and display. Learning to know what is natural and what is man made in your images is the key. Practice with some real objects. Run the side scan around the known object to see the image from different directions. They will not be the same from different angles. For a wreck the best is to go parallel to the length of the wreckage. Anchors are very difficult to see. You must be very good and have experience to see only an anchor.

[Unregistered]

Thanks ...

First of all thanks a lot for your reply ...

Your suggestion about anchor image would definatly help me. As in the past , customer wanted to have some image of known object and he selected anchor for the purpose.

No wonder, it was quite tough to get a good image.

Can you please suggest some object , easily available on the vessel , which can be thrown into water and obtain good image. I was advised to go for Drums and Tyres..I tried it too....but it is simply not possible to drown those easily.

I would request for your comments & suggestions on CMAX system & software , if any.

Thanks .

Ajay.

[Glennk]

Can you please suggest some object , easily available on the vessel , which can be thrown into water and obtain good image. I was advised to go for Drums and Tyres..I tried it too....but it is simply not possible to drown those easily.

Please register with the forum, that way it will be more easy to identify whom we are talking with.

As for the objects, you know that you must fill the objects with water?
A tyre need to be weighted, and maybe make some holes for the air to escape, as it can be many litres of air in a tyre without a rim.

A empty drum should not be to dificult to drown, just fill it with water and it will sink. Thus not the plastic drums, as plastic floats.....

Glenn

[UWLocator]

Try this info

You might want to read through this topic. There were some suggestions there that may help you.

http://thunting.com/geotech/forums/s...ad.php?t=11298

This was mainly about using markers for objects located but the markers may be of use to help learn what objects and shadows look like. Remember that the shadows sometimes give a better idea of what you are looking at.

Good luck,
Rip