Who has any results with fishfinder sidescans?

[René Pascal]

Up to now the only results obtained with fishfinder-transducer sidescans or fishfinder units I have ever seen are the ones by Dan Fountain. I would be interested to see any other images or hear from any other results with such systems. If you use a fishfinder electronic the data can´t be stored (only a photo/video of the display can be taken), but perhaps those may write a very short field report? Also bad experiences may be worth a lot.
I think this could give a very interesting collection of experiences.

[GBurton]

Re: Who has any results with fishfinder sidescans?




Hi,
The units that I have built and am in the process of marketing are based on Lowrance echo sounders (fish finders). They record data to MMC cards which is why I use them. They have custom external microprocessor circuitry added to them as well as custom made transducer. You will find many more images in my other postings over the past couple months. Here are some rocks in a 100 ft range.
Regards
Garry

[René Pascal]

Re: Who has any results with fishfinder sidescans?

Hi Garry,

your picture looks really nice! I did not find any pictures posted by you in the forum search, did you post them under GBurton?
Which unit from Lowrance do you use, and can it save the sonar echoes as raw data, or does it only save the sonar display data? I have the Lowrance X136 DF, and the mode that comes closest to a normal sonar mode with gray levels is "fish reveal", but it is a mode that is a little bit of a mixture between gray levels and grayline. It is possible to supppress grayline, but not completely, because then the gray levels are also reduced . The normal fishfinder mode paints weak echoes black on a white screen and adds a grayline to stronger echoes (if you enable grayline). That´s not so nice for sidescan, one reason why I thought about feeding the signals to a notebook. But if other models can save the raw data the complete systen would be more compact.

[G.Burton]

Re: Who has any results with fishfinder sidescans?




Hi,
There are a bunch of shots posted by me under G.Burton including shipwrecks. I will post some again below. The sounder I used for these images(raw, no'photoshop')is a LCX-15mt.
Other Lowrance / Eagle models are also useable, but all of them I know of have an annoying problem when used for sidescan that I have removed to a large degree with external propriatary microprocessor circuitry. These sounders record raw image data that you can 'colorize' etc on your computer. I generally run zero greyline and reverse greyscale to give a more recognizable positive image. None of them will work for sidescan imaging without a proper imaging transducer.
Regards

[G.Burton]

Re: Who has any results with fishfinder sidescans?




Here's another, bottom details....

[Charles, Oak Island,NC]

Re: Who has any results with fishfinder sidescans?

What other Lowrance/Eagle units would work just for the sonar not GPS ?

[René Pascal]

Re: Who has any results with fishfinder sidescans?

Really very nice sonograms, congratulation!
Did I understand you right that also the LCX-15-MT has this problem that you cannot display the data in a normal "clean" gray level mode without grayline? But the data that are being saved are raw data, not display data, and they can be displayed with the help of a program that you wrote by yourselve I suppose?
I just read the manual "LCX-15MT_0133-49.pdf" that can be downloaded at the Lowrance website, and there is no hint in the manual to a mode with gray levels only. They also give no information about how the data are stored on the mmc card.

[G.Burton]

Re: Who has any results with fishfinder sidescans?

Hi,
Thanks. I believe the recorded data is raw data as you can manipulate the heck out of it, change gain, color etc on a recorded file, just as if you were making such adjustments real time. GPS and other data are also imbedded in this file. I have no idea why they are so lame in their advertizment and documentation of their recording ability.
The greyline functions seem to change the display 'gain' as it detects targets of a certain strength. I believe it was done for better target separation. It does wierd things though when trying to get photo type images in a sidescan application as you look at them in real time, which is why I prefer not to use it.
The problem that I wrote about is something completely different and is inherent in trying to use these sounders in a sidescan type of mode. They are not ment to be used that way. The problems involve stability and there are several of them.
Regards

[G.Burton]

Re: Who has any results with fishfinder sidescans?

Any of them that are any good for sidescan use and the ability to record the images have GPS capability and either come with the sensor or you purchase it seperately.
regards

[Jim Kennard]

Re: Who has any results with fishfinder sidescans?

Nice images.

Are there any electronics in the towfish package with the transducer?

What is the maximum length of cable are you able to attach to the towfish?

What is the horizontal and vertical beamwidth of the transducer that you have designed?

What is the actual usable range of your side scan system at the point when you are able to identify a target as a shipwreck for both 50Khz and 200KHz?



www.shipwreckworld.com

[Charles, Oak Island,NC]

Re: Who has any results with fishfinder sidescans?

I'm already running two gps programs on my boat. The gps for the sss will not be acurate since the GPS transceiver is on the boat and the tow fish at pre determined distance behind and below. without the operator doing some math the position of any target will be inaccurate. Unless, you have found some new (gps)unit to implant within the fish and is capable of transmitting and receving underwater.

http://www.wadespage.com/D800DS07RF00.shtml

[G.Burton]

Re: Who has any results with fishfinder sidescans?

Hi,
Thank you. There are no electronics in the towfish, however there is a microcontroller in line with the Sounder. I have not tried a cable longer than 100 ft. Long cable runs are not recommended. This is ment to be an inexpensive system used for wrecks etc at sport diving depths. Max range to identify a shipwreck? Could easily see the 'Water Witch' in Lake Champlain as a wreck with detail 300 ft away, did not try it further except on geology. I've made two 200KHZ ducer models, ~ 1.8 deg by ~ 30 deg and another at ~.9 deg by ~ 30 deg. I don't have a tank so these are estimates. A 50KHZ ducer is in the works.
Regards

[Mike]

Re: Who has any results with fishfinder sidescans?

Can you tell the group how to make home-made transducers the way you do it or is that your secret info.? What are the hardships, material costs, calculations,etc. involved in making the underwater tranducers. Your pictures are phenomenal.

[G.Burton]

Re: Who has any results with fishfinder sidescans?

Hi,
Glad you like the pictures. Because I intend to sell these, it would not make sense for me to go into construction details. The basic semi kit form will be very inexpensive, relatively speaking.
Regards

[Charles, Oak Island,NC]

Re: Who has any results with fishfinder sidescans?

Some come to share (as was the purpose of this forum) some come to sell.