Humminbird Auto Chart

I’m running a MEGA SI G3 Helix 7.
I would like to do some custom mapping this season, Auto Chart is part of the reason I went with a Helix.
After a few YouTube videos, I thought I had it figured out, but then I read the manual. The manual explicitly states (page 197) that only a 2D down beam transducer should be used, and any side imaging should be turned off. I didn’t see any mention of that in any how-to videos I watched, and even the Humminbird tutorials seem to show side imaging being used to create Auto Chart maps.
Do any of you use only 2D for creating maps? Mapping is a rather tedious job as is, but with only 2D mapping, it would be a huge PITA – especially shallow water. I’m virtually certain that using SI is the norm, I don’t know why it wouldn’t be, but thought I’d ask here.
Also, if using Side Imaging for mapping, how far out do you set your range?

I’ve only used 2D. Never thought of using SI. Might work tho. The 2D works pretty slick.

Would be sweet for SI to work, following closely

Interesting. I have very little experience with custom mapping with Bird’s (did it in a buddy’s boat a couple times), but don’t remember side imaging being an issue.

I don’t think the range will effect anything at all, your transducer is always reaching out as far as it can, your range is just displaying what you want to see (at least that’s how I believe it’s works?)

With my Garmin stuff I haven’t noticed any difference while mapping with SI displayed, but it’s obviously a completely different interface.

It will map just fine with your SI turned on.

That said, it does NOT record any depths out to the side of your boat. Rather, it records the depth from your 2D sonar ping straight below your boat and draws a map based on that. In fact, the map that it draws shows that same depth in a swath that’s wider than your boat out to either side because it’s just assuming a constant depth over that width. This is why it’s important to make multiple passes from varying directions when creating a map of a piece of structure with changes in contour…especially steep breaks or quick changes.

If you are overlaying the SI image on your map, that is only a visual – it doesn’t know the depth for contour map creation out to the sides, just under your boat.

This becomes more obvious when you do this:
> Menu > AutoChart Live > Show Raw Data
It reveals the actual recording you’re making rather than the nice (wide) contour map, and you’ll see it’s just a single data depth point.

Here’s some sample pictures (borrowed from Technological Angler) of the same piece of structure in the map and raw data views.

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This link contains more than you’ll ever need to know about AutoChart in one convenient spot – links to lots of info from Humminbird, various experts, both text and videos.

http://www.bbcboards.net/showthread.php?t=1165416

Hopefully it’s okay to link to a different forum.

Thank you for the link Michael C. Winther, that’s a lot of info.
So it looks like mapping an entire small lake is going to take a while to achieve an accurate map with 1 foot contours. I was hoping that the SI would make it possible to do at least a 50 foot swath per pass.
Oh well, once it gets a bit warmer, I guess I’ll take off my shirt and get some color on my fat belly on days when the fish aren’t biting. Then eventually, I’ll have a very accurate map of the places I fish most often. It will be worth it once completed.

Another thing to think about as you are spending all that time and effort making your custom maps is to be sure and backup your data from the zero lines card. If your card would be damaged or corrupted you would be SOL.
I back mine up 2-3 times per season to my Google Drive files – that way they are stored to the cloud and even if my zero lines card and PC happened to go belly up at the same time I would still be able to retrieve the data and reload a new zero lines card.
The BBC link in the post above has some info on how to backup the data files from a zero lines card.
barc

I use it quite a bit on unmapped lakes or to get better detail of a hump or point on lakes that are mapped. I think that’s where it’s more realistic – mapping out a small area. You’d have to spend an immense amount of time to map out an entire lake if it were larger than 100 acres.

My fishing is concentrated on just a half dozen or so lakes these days, and I know some spots that I need more detail. Spot on the spot if you will.
One of the lakes is a very small private lake (around 60 acres) and is not on any maps, so there is zero info available. That lake is my primary target for Auto Chart. I don’t mind relaxing in the boat and making a map on a nice day. It will be very valuable to me once done, for both open water and ice fishing.
I do intend to save my maps on a Zero Line card because I definitely don’t want to chart a lake more than once. Great to see I can back up the files without having to purchase Auto Chart Pro.

I use the mapping a lot in Canada and here in wisconsin. My take on this is as you troll and map each pass you make just makes the map more accurate. On a new lake I do the shoreline twice or three times around before I do the back and forth. It does a better job if you crisscross as instructed. I usually dont unless I’m trolling open water suspended walleyes in july or august. I run a 7 and a 9 on my boat but map primarily with the 7 on the front trolling motor as it kinda warns you of shallow water reefs before you bottom out.

Mike

50 foot passes with 2d sonar will be more than enough to create the map you want.

If you have the laptop version of Autochart (autochart Pro) you have the option of viewing bottom hardness and vegetation. which is recorded via SI. I dont use that function. but letting you know its available.

Do not forget to set your depth offset or at least check it each time on a lake you previously mapped or are mapping.

Thanks for the tips guys. Hopefully I can get out there and start mapping soon.

Found a couple snapshots of a point I fished a few times last year – one picture of the lakemaster map and one with the autochart data I generated. Kinda cool.

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That is cool slough. Exactly the kind of information I am hoping to discover.