useing a fish finder in salt water

[1989 celebrity]

why is it that they say you can use a fish finder in freshwater but do not say you can use the same unit in saltwater? what is the difference ? i am looking for a good unit that i can use in both freshwater and salt also any suggestions? I am going to use it along side ofa FURUNO GP32 gps unit thanks in advance

 

[Bondo]

Re: useing a fish finder in salt water

why is it that they say you can use a fish finder in freshwater but do not say you can use the same unit in saltwater?

Ayuh,... Donno... Who is They,..??

I use both my sonars in both Sweetwater,+ Saltwater....

 

[seabob4]

Re: useing a fish finder in salt water

why is it that they say you can use a fish finder in freshwater but do not say you can use the same unit in saltwater?

You really need to stop listening to "them"...

 

[john from md]

Re: useing a fish finder in salt water

Most good quality fishfinders have a selectable program for fresh, salt, shallow and deep water. This adjusts the sonar to the density and depth of the water.

Regards,

John

 

[dingbat]

Re: useing a fish finder in salt water

Most good quality fishfinders have a selectable program for fresh, salt, shallow and deep water. This adjusts the sonar to the density and depth of the water.

Regards,

John

The good machines don't have selectable "auto modes"

The 2.5% density difference between salt and freshwater does not really amount to a hill of beams to begin with. Does it matter if that fish is suspended at 6?7? or 6?9??

The problems with those types of programs is that they use a fixed offset to the measurement values. Unfortunately, this approach doesn't reflect the dynamics of a water column. In reality the density of water changes by salinity and temperature. Unless you have a means of measuring the water temp and salinity throughout the water column, and the ability to compensate individual returns, why bother? A fixed compensation method could be introducing more error than its correcting.

 

[seabob4]

Re: useing a fish finder in salt water

I think we have a pissing contest here...

 

[john from md]

Re: useing a fish finder in salt water

I think we have a pissing contest here...

Not really. I was just stating what I know from reading manuals and web sites as a lay man. Dingbat seems to have technical knowledge about sonar and correcting the marketing stuff that the manufacturers put on their web sites and in their manuals.

I'll probably still keep selecting fresh or salt, shallow or deep when I do my setup just because it gives me something to do when the fish aren't biting.

 

[dingbat]

Re: useing a fish finder in salt water

I think we have a pissing contest here...

Not really. I was just stating what I know from reading manuals and web sites as a lay man. Dingbat seems to have technical knowledge about sonar and correcting the marketing stuff that the manufacturers put on their web sites and in their manuals.

John is 100% correct. No problems here. Just trying to make a point

As a Regional Sales Manager for a large analytical equipment manufacturer, I?ve spent the last 30 years measuring, detecting and quantifying various conditions and materials. Stating that you can measure or have a means to compensate for something that is, for all intensive purposes, unverifiable is pretty safe marketing gimmick, most of the time. But ask the Salesmen to put a sigma value on their claim and the he'll start mumbling under his breath defer your question to Engineering. Only then will you get a pretty good idea what the system can actually do. I spent 10 years as an Engineering Manager as well. Been there, done that