Boatist?? Pixels vs Power

[lowe160]

I am looking at two units, Lowrance vs Eagle. One has 480x480 Pix's with 2400 pep and the other has 640x480 pix's with 1500 pep. I only fish in 30 feet or less so the power isn't a problem there, but was wondering if the extra power will help with a better bottom reading when running?? What is the advantage of 4000 pep except for showing fish better at the deeper depth's?

Thank you, Wayne

 

[Barnacle_Bill]

Re: Boatist?? Pixels vs Power

In just 30 ft of water, 1500 Peak-to-peak power is plenty plus you will like the larger screen. You must be a ham operator. They are the only ones I know concerned about pep. BTW, Lowrance makes Eagles.

 

[Boatist]

Re: Boatist?? Pixels vs Power

Lowe
First both units you list have the same resolution, 480. The resolution is vertical resolution and it affects how small a fish you can see. For 40 feet of water 480 vertical resolution is more than enough.

In 30 feet of water you have 360 inches and with 480 pixels each pixel in equal to 3/4 of an inch. I belive the fish need to cover at least 2 pixels for you to see it as a fish so the fish need to be 1.5 inches high.

Of course most units today have a 2 and 4 times zoom. So if your fishing the bottom 1/4 of the water at 30 feet or 360 inches with 4 times zoom your looking at 90 inches devided by 480 pixels so each pixel equals .1875 inches and 2 pixel equals .375 or a fish less than 1/2 inch high.

The horzional resolution of 640 is just history. Remember the only thing that is under your transducer is the right most row of vertical pixels. Unit sends out a ping then waits for the return. As echos come back it fill in the right most row of vertical pixels. Next it moves that row one pixel to the left and then starts over. Sends out another ping and waits for the echo to come back again mark the returns in the right most row of pixels. So right most row is whats under your transducer now and everything to the left is history. Stuff on the far left is the oldest history. This can be an advantage when trolling. As your trolling and mark fish you can note their deepth and if you know how deep you lure is you can raise of lower it to be just over the fish before the lure get to the fish. Depending on your trolling speed and chart speed with time you know when to expect a hit.

1500 PEP watts or 187 Watts RMS is plenty of power for 30 feet. When running most important thing is how well your transducer is mounted and how much air or turblence is under the transducer. Likely when running you are going to run in water over 30 feet. Good thing is the bottom sends back strong echos so you should be able to see it easily out to 100 feet of fresh water.

Older units had more controls to adjust for running, like a surface clutter control. New unit in auto mode will try to adjust for you but i think they do it by changing sensitive. If your transducer is mounted correctly in a good spot should be able to see bottom at least to 40 MPH.

Advantage of 4000 Watts PeP or 500 Watts RMS is in deeper water. I think it is actually a disadvantage in shallow water. Put your foot or hand under the transducer and you will feel the ping of the unit. With higher power it is much stronger and can be felt further away. If You ever want to start a arugment go into a fourm with a bunch of Experts and ask does the ping of the fish finder scare away the fish.

Along the same line many fish are hard to see. Salmon in one that about 50 percent of Party Boat captains will tell you, can not be seen on a fish finder. Other will say can not see the Salmon but can see the anchovies in their stomic. Anyway higher power will help you to see small and hard to see fish down deep. In Saltwater must have some extra power or can go with a narrow cone angle like 8 degrees which puts all the power in a smaller area.

 

[bruceb58]

Re: Boatist?? Pixels vs Power

Boatist,

I am curious how you came up with your RMS numbers.

Bruce

 

[jtexas]

Re: Boatist?? Pixels vs Power

...
If You ever want to start a arugment go into a fourm with a bunch of Experts and ask does the ping of the fish finder scare away the fish.
...

In my experience you won't spook actively feeding fish at 20 feet with the eagle 480, or with a dozen boats all with sonars going, or two dozen boats. Get much shallower than than that, maybe 12 or 15 feet you're not likely to see the fish you're going to be catching. I'll confirm boatists assertion that vertical resolution is the one that counts, more horizontal screen might be handy from time to time expecially if you like to use a split screen.

 

[lowe160]

Re: Boatist?? Pixels vs Power

Thank you very much Boatist. I am looking at the X510C Lowrance or the Fishmark 640C. I fish smallmouth 98 % of the time usually in 15 feet or less. I mainly want the unit for structure so I guess either would be just as good. Whatever I can get the best deal on. I have a Eagle 320C one the bow and a Fishmark 320 Monochrome on the dash at present but have gotten spoiled with the color as you can tell at a glance the type of bottom. I have Vexilar aluma-ducer mounted thru hull and it works great.

Again, thank you for your resonse, Wayne

 

[whiteman]

Re: Boatist?? Pixels vs Power

I do 95% of my fishing in less than 150' of salt water and the Lowrance X135 (mono) with 480x480 is a brilliant unit. In Australia, we are yet to see the X510 but I've fished with the 107C and it is very good. The extra vertical pixels in the Eagle 640 look good in the specs and I reckon this is where Lowrance is headed in the near future. Interesting that it is available in their "B Grade" line-up.

 

[Boatist]

Re: Boatist?? Pixels vs Power

Bruce
Not sure I understand your question. If you mean that 4000 watts PeP = 500watts RMS it just the way it is. Take PeP watts and divide 8 = RMS watts or RMS watts times 8 = PeP watts. Some sites will have both rateings so you can see for yourself. RMS watts was the standard but lately more and more are useing PeP watts just becaus it sounds better. Many do not understand the difference that is why I try to point it out.

 

[Boatist]

Re: Boatist?? Pixels vs Power

jtexas
I think it probably does have an effect on some fish and the more power you have the deeper it will efect fish, but to me makes no difference as I do not belive I ever caught a fish that was in my cone angle. I probably have offshore when fishing deep. I suspect some fish it may scare and other may go and try to find what making that noise. So maybe it helps and maybe not. I find it funny when people swear it one way or the other.

 

[Boatist]

Re: Boatist?? Pixels vs Power

Lowe
I have not seen any of the Lowrance 500 serries yet but from what I read pretty much the same units they have had out for a long time with different built in maps. It appears to me most units will be out in spring to summer. I hope they are able to get out for the winter boat shows.

I do not like the way their putting maps on them. Example one unit they include all the costal charts. I fish the pacific ocean off California but would never drag my boat all the way to the east coast to fish the Atlantic Ocean. Instead I would rather see the California coast and the entire state of California rivers and lakes.

I was hoping they would come out with more dual frequency units with 200Khz transducers and 80Khz transducer or even better 100 khz transducer. Likely they are having trouble with the new frequency. Maybe harmonics interfearing with Vhf Radio or something like that.

I often fish in ocean waters deep enough that 200khz does not work well. 100 or 80 khz should meet my needs well. Still most of the dual frequency are 50khz and 200khz.

Lowrance color units hard to beat, Their bright and can be seen from most any angle or even from the back of a boat like like mine.

Whiteman
I agree the 640 vertical is probably best for deep salt water in the Lowrance/Eagle line. Furuno I feel is the best deep Saltwater unit as they have many features to help you see fish deep but even their new brighter screens do not compare with lowrance.

While Lowrance had many of the same deep water features they went away from them when they went to the menu driven systems. I guess they feel most will not read the book and learn to use their units. With the menu sytem really very little need to read the book. The feature I really like and has made me keep my 1981 X50 unit is called BOTTOM TRACK. Fishing deep you can still see fish on the bottom without super high resolution. Fish 400 feet deep you just set Bottom track for bottom an up 20 feet and unit will track bottom and 20 feet above bottom will be the top of the screen. You can acutally set for bottom and up 10 feet or any number of feet over 10 feet. I usually use bottom and up 30 , 40 , or 50. With todays unit best you can do in auto mode is 4 times zoom so your looking at 100 feet, not to good for seeing small rock fish.

 

[bruceb58]

Re: Boatist?? Pixels vs Power

Bruce
Not sure I understand your question. If you mean that 4000 watts PeP = 500watts RMS it just the way it is. Take PeP watts and divide 8 = RMS watts or RMS watts times 8 = PeP watts. Some sites will have both rateings so you can see for yourself. RMS watts was the standard but lately more and more are useing PeP watts just becaus it sounds better. Many do not understand the difference that is why I try to point it out.

OK..you are just going by the specs on these units. Unless you know the duty factor of the pulse, there is no way to figure out the RMS unless they tell you.

Dividing by 8 is just a number that would be assosciated with a particular duty factor from a particular vendor. Could be that all of them use the same duty factor.

I know that many military sonars would not have that same factor of 8.

 

[bruceb58]

Re: Boatist?? Pixels vs Power

I have the Lowarnce 337 and just bought a memory card for the oceans and one for the California Lakes...between the two cards I paid less than $150.

I am very pleased with my Lowrance unit and very pleased with the mapping. It was much better than the comparable Garmin unit.

 

[lowe160]

Re: Boatist?? Pixels vs Power

Boatist,the X510c is just sonar no gps. I am looking at the H2O for gps mapping as i would have multiple use's for it. Being a hand held I can use it for travelling and hunting, it has a 2.83" dia. screen and the 5" sonar's i don't think would be much bigger running a split screen. The combo unit would be better running full screen on gps BUT running in unfamilar territory you would not see the bottom coming up and that could be a disaster!

Wayne

 

[Boatist]

Re: Boatist?? Pixels vs Power

Bruceb58
PeP and RMS are two ways to measure power in a AC signal. RMS is a AC signal applied to a load that will produce the same heating as the same DC power. PeP is Peak Envelope Power and just a different way to measure. These are two standards but what is important is to know how to compare the two when comparing two different units to tell which has more power. There comparing the power durning transmit or ON time. It is just a AC audio signal mesaured durn on time.

Duty Cycle a factor in transmiters and power supplies is more a factor of how long it can be On as compared to OFF with out over heating. In a transmiter may be 3 minutes on followed by 2 minutes off. Military transmiter usually have a 100 percent duty cycle plus. Meaning they can transmit 100 percent of the time without overheating.

For Me the 8 times factor between RMS and PEP it is enough to know that Eagle, Furuno, Garmin, and Lowrance all use the same figures. I have not checked other brands as I am not going to buy any of the others.

I also agree that Lowrance Base maps are better than Garmin base maps and the upgrade maps look to be a better deal also.

I own a Garmin GPSMAP 76 I bought when it first came out. The units base map has buoys both ocean and inland. No updates or anything like that but all I needed for my needs. One thing that turned me against Garmin is later GPSMAP 76 units they removed all the buoy data and downgraded the base map. I ask my self since they had it all programed why did they do this. I can only think of one reason and that is they want to force you to buy upgrade maps. Lowrance Base maps of all the units I have checked still have all the buoy data. If you need contour maps and depth reading you still need to buy up grade maps

 

[Boatist]

Re: Boatist?? Pixels vs Power

lowe 160
If you have the room and can afford a Depth Finder and a GPS then Seperate units are better in my opinion also.

With a dual unit any thing you want to change you first need to make sure your in the right mode before you make the change. Example your approching your fishing spot and want to do a 4 times bottom zoom to help locate your rock pile and fish targets. You hit the zoom in button only to realize you zoomed the GPS not the depth finder.

The Lowrance H20 or H20 C screens are so much brighter than the Garmin unit of the same size. Also the Lowrance at least in California has all the Buoy data even if you do not get the plus package. The only thing is the screen is small.

I have the Garmin GpsMap 76 and it works perfect but the screen is hard to see on the boat and very hard to see in the car. This year at the boat and tackel shows if I can find a good deal on the H20 C Plus I am going to purchase. I will keep My Garmin unit and use it when on a party boat just to capture location we fished. On our boat probably put it bag with our saftey raft just for a back up.

I have not seen any of the X500 serries but the spec look good. They are not in stores here yet and hope they get them to the boat shows this winter. Most of the new units like this will show in stores in late spring or early summer here.

When you get your new units come back and give us a review of likes and dislikes.

 

[bruceb58]

Re: Boatist?? Pixels vs Power

Boatist,

I sent you a PM.

 

[ECHO 1]

Re: Boatist?? Pixels vs Power

Just in case yall dont know, you can go to Lowrance's
web site and download Inhanced lake maps that show contour,depth and some show structure as well for free.
They dont have every lake but they do have a lot.