Although I am tremendously impressed by Reefmaster, there are a few things that I would really love to see implemented...
Gear: Lowrance HDS7 Touch, 2x LSS2, P66.
I am using a Towfish with one LSS2 down to 45m (on a 100m line).
Since the software can look at the DI signal from the Towfish (for TF depth, knowing that the line is 100m, I would love an AUTO OFFSET ADJUSTMENT (via triangulation - HDS 7 using the P66 Sonar on the boat for total depth under the boat and LSS2 from the Towfish, providing SS and DI).

I would love a feature that allows for OPTIONAL SideScan contour(feature) mapping, using the DI channel as depth reference.

I really LOVE the SS enhancements that are already there, but I would like to be able to adjust a gain/m for a given section or at least the amount of auto gain. A HISTOGRAM (adjustable) would also be greatly appreciated! There is so much more information in those SL2 files...lets make most use of them... Also, some AntiAliasing please :)

A snipplet tool for the SS tracks (like in premiere, where u can cut a long track into short tracks, eliminating errors by waves/surge, later corrected by a new scan/file.

Slant Angle adjustment sliders - the Auto feature makes a lot of mistakes - I'd rather keep a tiny bit of water and side-offset-error and get DI features on my map - especially with wrecks and interesting structure!

MOSAIC-FEATURE-MAPPING - multiple passes that can be combined into a stitchless texture by feature-mapping/combining different passes, making borders transparent (a.s.o.) - sometimes surge/waves/other boats make an evenly-spaced multipass impossible. Looking at structure from different sides (with SS) and being able to combine these files into ONE would be highly beneficial.

Heaps and heaps of work, I know - but I'd be happy to invest and Beta test, since I am out nearly every day... Thank you :]

Hi,
Thanks for the feedback and suggestions.

1. "Auto offset". Which offset are you talking about? Distance behind the boat? Do you mean that you can enter the length of towfish line, and use the recorded DI depth and depth underneath the boat to compute the distance of the towfish behind the boat? Easy to do I suppose, let me know if I have understood correctly.

2. Contour mapping using DI depths. Just the same as current mapping but using DI instead of primary 2D channel?

3. The auto-gain is rather more complicated than a simple histogram across signal range - that doesn't work (we've tried it..). We could offer some parameters to tune the A/G a little, and maybe we will in the future. As far as making the best use of SL2 data - I'm not sure you'd be missing much with the current auto-gain. You might be surprised at just how poor the signal range is at the fringes of SL2 data. If you think there is a lot of usable stuff that RM just isn't showing well, please forward some example files (DropBox or similar, link to This email address is being protected from spambots. You need JavaScript enabled to view it. ) as we are always looking to improve.
What context are you referring to anti-aliasing in?

4. You can cut your tracks up once they are part of mosaic, but not in the track review. Add a track to a new mosaic and use the range slider in conjunction with the Split Segment command (right-button menu) to cut tracks up - you can the hide or delete the bits you don't want. You should be able to get exactly the feature you are describing (i.e. add further tracks to the same mosaic and fill in the gaps).

5. The slant range adjustment is done based on depth under the boat. Errors will happen because the depth of the feature is not the same as under the boat, but unfortunately this is a limitation that we have to live with. One day we may add the possibility to use bathymetry as part of the SRC calculation, but I'm not convinced of the merits of making SRC user adjustable - at the end of the day it is a very simple bit of trigonometry. Other errors are likely as a result of position or heading - the latter should improve when we implement support for GPS compass headings (assuming you have one).

Mosaicking is possible now by adding multiple tracks to a Sidescan Mosaic, and the exports are (relatively) seamless if the Fade swath edges option is used during export. Adjusting mosaic location through feature mapping is pencilled in as a possible improvement - but we need to do a proof of concept first. The main issue is determining which feature is in the "right" position.

cheers,
Matt

Hey Matt,
thank you so much for the quick reply. Let me get right to it, let me quickly explain my setup: I am running around Malta with my little boat, trying to find some new wrecks. My target depth is somewhat around 50m. Since the SS angle is too steep to cast usable sonic shadows, I built a towfish with 100m of cable and an LSS2 HDS transducer. The towfish is now zooming along around 10-15m off the bottom (depending on how fast I go @ a given depth). My HDS 7 Gen2 Touch gets the DI & SS info from the fish and the sonar info from the P66 mounted on my boat.

1. My troubles at the moment: Aligning the sonar and DI/SS channel, so that when I find something, I can punch the waypoint button and save the position - however - the waypoint will always be saved (approx) 90m ahead of the target (because of the 100m cable between boat and towfish.)
I wish and pray that one day, there could be an automation in Reefmaster that lets me enter where I get my depth and position info from (in my case my P66 on my transom) and and adjusts my DI/SS tracks accordingly --- perhaps even to the point of them aligning again in the sonar viewer... ;)
[So: sonar/boat=total water depth | towfish=DI&SS channel (DI=transducer above seafloor in m) | Cable=100m |--- triangulate actual distance from boat to towfish)

2. I imagined something like this: Using a towfish, the DI channel can provide the depth of the transducer and the SS returns could map contour right and left of the transducer. Using triangulation between the transducer and a [strong] target-return could at least contour medium to large changes...

3. I am very happy with the A/G feature, however, I would love some control - gain/m for example - where gain can be adjusted to increase with distance. Sometimes the A/G seems to lower the close returns and kind "invert" the left or right side, making a dark, black band close to the center line.

4. I played with this and it seems to work alright, although I would just powerflow with something like a "razor"-tool in the sonar review that does all the splitting automatically for me (adjust,split,create new track with the rest of the data) ;)

5. Slant angle adjustment... can it be possible to select the DI channel as depth info? Any towfish SS images are nearly lost in the mosaic-view because slant angle takes most of the close data and smashes it into long lines and noise - if I could tell the program to use the DI channel for depth info, the sonar channel for bottom composition and SS for images, that would be perfect) Additionally, I would love to be able to leave a tiny bit of water column in the picture - since many interesting features really show with the DI channel...

I know that a feature mapping function is a lot of work - bot scans of the same area from different angles/bearings/heights[towfish] would really yield breathtaking sonar maps... Something many people would love to get their hands on - towfish users or not... ;)

I know I am a special client - with my weird setup and towfish use - however, RM is the only affordable and user friendly interface out there and I know that people would buy it if it would be able to display towfish data as easy as transom data...

Kindest regards, J

I have some similar issues with the auto gain. It loses some data close to the tranducer but gains some far out at times. If i could combine the auto gain with the non auto gain images i would get all the data. I attached a sample

That looks possibly like a problem with the downscan channel?

On that note Matt, any chance that RM mosaic gain could be made to function with DS switched off ? At the moment, with both depth and data switched off on the DS channel the mosaic contains no useful data. With only the data switched off I have a more useable mosaic, but distances are way out. The image is way better on the HDS unit though.

T

AnglingCharts wrote:
Trevor, how are you using structurescan on your HDS? Old structurescanbox with LSS1, or Structurescanbox HD with LSS2, or Sonarhub with LSS2, or LSS2 directly connected to a Touch unit?

Danny,

I still use LSS1 and HDS8 gen 1.

I have a 10ft tdx extension cable rigged with 2 switches, one on the yellow wire, one on the white wire. I used an extension so that I didnt need to hack into the tdx cable itself. The yellow wire carries DS data, the white wire DS depth. By switching the yellow and white off I lose the all of the interference from the DS. With the white on I have minimal interference and DS depth available - with the both on I have the usual DS interference causing the dropout regions close to the water column.
With only yellow off I still have DS depth available, and RM mosaics reasonably, but with apparent geometry errors, with both off I have a mosaic with no gain at all (unuseable).
Removing the dropout region has given me much improved ability to record and view structure close to the vessel, and the high angle of incidence seems to result in better lakebed penetration - revealing buried structure.

T

Thanks Trevor. This is new information to me. It is the first time I read someone is using the Structure scan this way.

Any progress on the feature requests brought up by JK4U and issues mentioned by fisher?

Top priority for me is the side scan auto gain "inverted" issue. Detail is lost near the center and gained near the edges.

A lot of these features are in development now, including changes to autogain that allow the "amount" of AG to be adjusted with a slider. The only solution at the moment for your issue is to simply turn off autogain for tracks that it does not improve.

Sounds good. Are there any rough time plan for this?

Hey T - that is exactly how I improved my scans as well. Since I just made another small towfish, I took the time to take pix of the actual cable mod. I posted the rundown here:
reefmaster.com.au/index.php/forum/reefma...an-node-removal-lss2