Thread: 5 inch si verses a larger si question

I have a Lowrance HDS 5 and very recently added the LSS-1 Structurecan. 1st, it is totally awesome. 2nd - When I was researching what to buy, as you know, the one thing everyone always kept saying was buy the biggest screen you can afford. The HDS 5 was really all I could afford and was thinking it would be fine because when I would be using it, I would be sitting right in front of the screen so would have no problems seeing everything.
Turns out while that is sort of true, a 5" screen when using the side scan is not the easiest to make out no matter how close you are sitting to it. You have no problems picking out larger structure, but seeing actual fish and the smaller stuff gets kind of tricky.
Mine often shoots out 300' and it is just too much info on too small of a screen, so I pull it down to no more than 100', usually 80'. If I am actually using the side scan to find a fishing spot, I have found it is best to set it to read left or right only i.e. I will set the range to 100' and stay out 100' making my pass.
It is much easier to read that way because then i have a full screen dedicated to just one side. Yes the pixel count is the same, but instead of only having half a screen to pick up smaller details, I now have the full screen. It works MUCH better this way on the 5" screen.
Forget about using the tri-screen on the 5" screen. I am sure some people would have complained if it was not available, but I seriously doubt anyone actually uses it.
I did pick up a 2nd HDS 5 , used in excellent condition for $360.00 and mounted it in the bow. When I am in the helm looking at that one, it really, really makes me want to mount the 2nd one alongside it so i could view down scan and side scan at the same time (I am "new" school and prefer down scan to 2D) BUT I would then obviously miss not having one in the bow.
I have the one in the bow on a Ram Mount sticking out as far as it will go. When sitting in the fishing seat there is no way I could make out much on side scan unless it was a big tree etc.....even on down scan I have to lean way in to make out the smaller details -i.e. is that a small tree or tall grass - did I see fish in that tree ? .
Bummer for me is I have great sight at a distance, but need reading glasses and it is right at the in between point so I find myself having to lean in even further to see small details.
So I thought the HDS 5 was the most i could afford and about 5-6 months later I bought the 2nd HDS 5 for $360.00 - getting close to the HDS 8 price range, tho I would have been without it during that time, but i do now find myself almost wishing I would have waited. It is a whole lot easier tho to spend $600.00 at a time than plopping down $2k. Just doesn't "seem" as I have spent as much
But if the 5" is all you can really afford, you still won't be sorry. I see it really drastically changing my fishing. I always fished with my brother in his boat so never really did much with 2d sonar. When I got my own, I was not very good at interpreting what i was seeing. I fished the heck out of this one area because I always saw a ton of fish at around 30'-40' in water that was 85'. Drove me nuts because no matter what i tried, i could never catch a thing there.
1st place i went when I got the StructureScan - turns out it was the top of an old tree that had hundreds of tiny branches. I am guessing it was so dense it did not pick up below it so i never saw it going all the way to the bottom. One pass with the StructureScan and while I felt stupid, I did feel better about never catching fish there....

Originally Posted by genec

rnvinc,thanks for the information on the first question, do anyone know the answer to the second question about when water colum gets deeper do it still give you all the picture and condense it into a smaller aera?

Looking at the depiction below....( and this is how I understand it...I could be wrong ....again...)

The red line "1" is the distance from the xducer to the bottom straight down...directly under the xducer...
(In effect... this red line "1" is the "inner edge" of the left and right SI beams butted up against each other) (the left and right SI beams "inner edges" actually overlap somewhat but that is not important for this discussion)

When the image is processed....and plotted onto the screen...:
.....a. the left SI beam vertical "inner edge" is flattened out on the image (shown in the depiction as the left side of the dark blue water column...from the boat's center line to the where the dark blue water column meets the light blue bottom)
.....b. the right SI beam vertical "inner edge" is flattened out on the image (shown in the depiction as the right side of the dark blue water column...from the boat's center line to the where the dark blue water column meets the light blue bottom)

This process (of plotting the water column as flat "in line" with the bottom) actually includes the water depth as part of the distance in the setting "SI Range"...

So if the "SI Range" is set to 50ft, and the water depth is 10ft...:
From the center line out in the SI image:
....a. the left water column is 10ft, and the left bottom coverage is 40ft
....b. the right water column is 10ft, and the right bottom coverage is 40ft

If the "SI Range" stays at 50ft, and the water depth increases to 20ft....:
....a. the left water column is 20ft, and the left bottom coverage is 30ft
....b. the right water column is 20ft, and the right bottom coverage is 30ft

In order for the unit to show the same amount of actual bottom ..the "SI Range" would have to be increased as the water depth increases....

Now...all this gobble-d-gook explanation is just the exploded version of what the other guys said.....
"As the water gets deeper...(and the "SI Range" setting is not changed)...subtract the water column depth from the "SI Range" setting...to get how much bottom is actually showing on the screen)...(this equation is probably not exact to the foot..but probably close enough for horseshoes and hand grenades)...

Rickie

I think genec was asking how does it appear on the screen. In the 50' deep 50' range example what gets displayed on the screen when viewing both SI sides would be divided in to 3rd's. 1/3 blue colum on left, 1/3 "black" water colum in the middle, and 1/3 blue column on right. The great picture Rickie posted shows that both of the blue sides would actually be the water column that is out to side of the boat 50' near the surface then as you go deeper it gets closer to the boat. Viewing just one side the "black" water column and the blue column would be equal sizes, and the blue would still be 50' near the surface then as you go deeper it gets closer to the boat. Unless as stymie wrote you were using a HB unit you could turn off the "black" water column and see just the blue column. It would still just be water column, 50' near the surface then as you go deeper it gets closer to the boat.

Hope that makes sense.

thanks guys, if I understand you right as deepth increase the water colum in dark increase IN WIDTH ON THE BOTTOM, rather than being straight under boat. And this would mean all your set distant is covered WITHOUT BEING CONDENSE. slow learner,all this new stuff goes right threw my head,old generation