So my dad called me today and asked a question that I was totally confused on.  He's looking for a new graph for his boat and wanted my opinion on which screen would be better.  I couldn't really give him a good answer.

Both are 16 level greyscale, similar dual beam transducers, etc etc...

One sonar has a resolution of 640 x 320 (250 RMS with 2000 peak to peak power)

Another has 480 x 480 (unknown RMS with 4000 peak to peak power)

What do you think.

In my opinion. the 640 would be better. it give the best detail for depth.

The width is all history.

id have to go with the 480 by 480.  but tell him to look for a unit with 640 by 480.  it probably wont cost to much more but it will be a little bit better then both.

I would go with the latter rather than the former due to the increased power.  160 fewer vertical pixels shouldn't be a problem.

I would go with the latter rather than the former due to the increased power. 160 fewer vertical pixels shouldn't be a problem.

How much do you honestly think the power matters though.  He's not going to be going much deeper than probably 100-150 feet for what he needs.

------------------------------

This is why I asked here.  Thanks for the input guys.  I really couldn't give him a good answer.

Depth shouldn't matter (at least not IMO and I'm no expert).  More power = stronger returns = better picture of the bottom.

Perhaps I'm wrong.

Depth shouldn't matter (at least not IMO and I'm no expert). More power = stronger returns = better picture of the bottom.

Perhaps I'm wrong.

I hope I didn't mean to make my statement say you were wrong.  Didn't mean that at all.  It does make sense that more power would equal a better return though.

burley is correct about the power. Most users cannot tell the difference in the pixel count when it gets over 480 vertical pixels or 17,533 pixels per square inch. The majority of the high resolution screens are that spec.