Humminbird Side Imaging Forums

General => General Discussion => Topic started by: tmx on April 26, 2011, 10:58:50 AM

Title: object size question
Post by: tmx on April 26, 2011, 10:58:50 AM

I would like to know if it's possible to improve the performace of SI on my HB 898 concernig the object size.

I tried to get the best SI picture of some reference objects well known from diving. There are three old rowing boats and a ladder in 10m (round 33 feet) depth. Two of them lie on each other. The boat on the top is maybe 1m (3.2 feet) over bottom. The ladder lies directly on the second boat. The third boat lies in some metres' distance.

I have marked the screenshot (455kHz SI). My question: Is it possible to reach better results and bigger object size? I tried several settings on the unit in playback mode without any significant improvement. Perhaps do I expect too much?

(http://i996.photobucket.com/albums/af84/SystemKopter/3-boats.jpg)

Title: Re: object size question
Post by: Rickard on April 26, 2011, 01:11:14 PM

Hi Tmx,

I think you got a typical and good image with such targets at that depth. I think SiView shows a little bit better detail so that's one way to improve things. Getting closer the target (within a few meters) is the only effective way to get significantly better image, but then you would need a towfish in this case.

Regards,
Rickard

Title: Re: object size question
Post by: sonar2000 on April 26, 2011, 04:47:25 PM

Measuring tools are generally a function of the external viewer review of the recorded sonar run.
This is why we carry a laptop with us so we can record and measure.
We dont use the zoom very often on the unit, as I dont think is shows much by way of measurement...
Chuck

Title: Re: object size question
Post by: tmx on April 26, 2011, 05:00:58 PM

Thanks for your opinion guys.

@Rickard: Tow fish could be an option. On the other side it's a little bit more difficult to handle on the water. I think about it..

@Chuck: Maybe my question was not precise enough. I meant not to zoom the objects but generally get it bigger due to (my hope) f.e. better settings.

I was a little confused as I saw the relatively new video of Lawrance structure scan in action. I know, wrong unit and wrong forum, please forgive me, but it's very interesting to see how it works:

http://www.bissclips.tv/bissclips-tv/technik/was-ist-structure-scan-2515.html (http://www.bissclips.tv/bissclips-tv/technik/was-ist-structure-scan-2515.html)

Title: Re: object size question
Post by: sonar2000 on April 26, 2011, 05:54:47 PM

The setting will not affect the size.  I guess that is why they added the zoom.
If you have a laptop or a notebook think about the external viewer such as Humviewer.
A little more work but it depends on your needs for the size. 
Also you could output your HB screen to a bigger screen.
Notebooks work well as they adjust to ambient light. Laptops generally dont adjust..
Let us know how this turns out..
Hmmmmm...you could look at an 1198.... ;D... :o ::).....
Chuck

Title: Re: object size question
Post by: Drifter on April 27, 2011, 08:14:11 AM

tmx,

Try using the SI Side menu option to switch back and forth from Both to Right (or Left ~ depending on target location). The unit should expand the side to fill the display (like a 2X magnification).

Darrell

Title: Re: object size question
Post by: tmx on April 28, 2011, 04:06:07 AM

Hi Darrell,

It's a good Idea! Thanks. The new image:

(http://i996.photobucket.com/albums/af84/SystemKopter/3boatsnew.jpg)