Down scan imaging question

[graingrower]

I am comparing a Lowrance Mark 5 DSI to a Humminbird 570 DI. I want to mount it on a 20 foot pontoon, will likely use it less than twenty times each year, and Mille Lacs would be the biggest water fished. Is downscan superior to conventional 2-D sonar? (I realize the 570 has both) Is there a better finder for $300 or less? Which type is easier to interpret?

[suncruiser234]

I would go with the bird because you can run both sonar and DI at the same time on a split screen.

[Deitz Dittrich]

I would say that regular 2D image is easier to read.. I have not messed with downscan much.. but I have Bird 977 on my boat and love SIDE imaging.. LOVE IT!!!! Would not have a boat without it.. But have not messed with downscan at all.

[Nick Kuhn]

My personal opinion is that without conventional sonar you will miss quite a bit. I think of down imaging as like a "CSI enhance" mode of conventional sonar. Most of the time you will have a pretty good idea what's below just from the sonar. If you still have some doubt, flip on the DI to get a better idea.

Personally, I never run just a DI screen. It's either 2d sonar + DI, or 2D sonar + DI + SI.

[fasternu]

I looked into this machine as well, and was told by the seller that it works great in shallow water, but once you get over 2o feet of water it is almost ineffective anymore, or at least won't be as easy to use as conventional sonar.

[pulleye16]

I've dabbled into this a little and here's some questions for you to ask and consider:

1) Find out which speed the DI works at (I thought it was around 8mph for best results) in which trolling,jiging,lindy riggin', and bobber fishing it won't work. I'll have to check my email for exact speeds...

2) How much cover does it have? The area DI covers vs. conventional 2d is actually a step back in technology. Very very small scanning area.

3) What are the purposes you want this? It really only shows structure and is not that well for fish finding...And it would take a long time to read the cover vs. SI.

I was extremely excited when I first saw this as a cheap alternative to SI but after reading reveiws and tech reports...many are saying it's a step back and not worth the money...better off getting 2d sonar.

IMO If you want something for reading the bottom structure, save up for the SI where you can scan out to 200' both sides, find structure and then use DI to get on top of it...

[Brad B]

I've dabbled into this a little and here's some questions for you to ask and consider:

1) Find out which speed the DI works at (I thought it was around 8mph for best results) in which trolling,jiging,lindy riggin', and bobber fishing it won't work. I'll have to check my email for exact speeds...

2) How much cover does it have? The area DI covers vs. conventional 2d is actually a step back in technology. Very very small scanning area.

3) What are the purposes you want this? It really only shows structure and is not that well for fish finding...And it would take a long time to read the cover vs. SI.

as for the speed it will work at, I have the HB 597 with the down imaging and it runs fine from 0 to 25 mph. I had no signal issues even at the high speeds. I found a sunken log and turned the spot lock on the ipilot the DI worked fine when I was stopped. the image was clear of the log when the transom of the boat would pass over it as the i pilot made the adjustments to stay on the spot. find the structure and the fish should be there. I like the down imaging so far over the 2d sonar but what is the best is to run split screen and see both at the same time