heres to pictures of crappie that i took today.
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heres to pictures of crappie that i took today.
is that with a humming bird or lowrance?
That first DI is tremendous. I would have interpreted that top arch in the second 2D as a crappie as well. My experience is that crappie show that narrow, tall arch with the yellow in the middle.
Great images. Thanks for posting.
Based on the figures I've seen from Doug V on BBC, that Crappie would be 12" tall based on 7ft of water. Seems a bit big for a Crappie. Nice pic though.
this picture might be a catfish. the shadow seems to be in a strange place though
I would interpret that shadow's placement as making the fish off to the side in the DI beam slice just a little...Quote:
Originally Posted by kosmo
Rickie
heres a picture of what appears to be two predator fish with some bait fish near by
Yes, prob not a crappie, but a cool, or Kool pic either way.
Nice pics
I believe those pictures are from a Humminbird 998c Si unit but Kosmo could verify that for sure.Quote:
Originally Posted by hatchieman
The picture Kosmo posted appears to be from a 998c Si unit Rickie, so that means the catfish was marked in at least one of the Si beams. That would put the catfish off to one side or the other. If Kosmo would have also posted a screen snapshot of the Si sonar we would know which side it was off to.Quote:
Originally Posted by rnvinc
Knowing it's a 998c Si unit, I don’t find the shadow strangely placed.
I’m not following you here mduncan62, those screen snapshots are showing from 7 to 30 feet of water, so where are you getting 7 feet of water from?Quote:
Originally Posted by mduncan62
Maybe I need to see what DougV posted in the BBC as I figure it’s about a 9 inch tall fish (hard to more exact without the original screen snapshot).
You got a link to DougV’s post on BBC?
I'm curious to know the clues of the image posting that indicate it was his 998c SI instead of his 597ci HD DI...(orientation of the split screen? Size of the depth digits? Lake bottom presentation in the image?..)Quote:
Originally Posted by Humminbird_Greg
I enjoy learning...:)
Rickie
The size and shape of the image he posted plus another post where he mentions his 998c Si unit… :biggrinQuote:
Originally Posted by rnvinc
I knew it was an 800 or 900 series unit by the shape of the screen snapshot and also from the location of the digital depth (this ruled out an 1100 series unit). The appearance of the Di sonar helped as well. I always fond the Si/Di to be more 3D looking in that I perceive depth to the Di sonar image versus the flat looking images from the dedicated single beam DI sonar units.
I'm pretty sure he is referring to using a ruler to measure the water column image and correlating to the actual depth. Then inferring an object's actual height from the object's measured height on the image.
I have no idea where his seven feet of water came from.
Quote:
Originally Posted by Humminbird_Greg
Very cool pics!
im at work right now and using my phone and just noticed something.i zoomed in on the structure in that picture with the crappie.theres a really good detailed picture of a fish on the right side and i think theres a fish on the left side but hes not as visable
i used paint to resize the area were the fish is
So 13ft of water is showing in Kosmo's pic, and you believe that fish is 9" tall? Love to see how you came up with that.Quote:
Originally Posted by Humminbird_Greg
... but, I think you all are missing some things, here. In Kosmo's first picture, it appears that the unit is measuring over 20ft of water depth ... and that's reading from the far right side of the image (possibly reading the "hump" as 20.7ft deep). Now, not being familiar with HB's, I would have to assume that the 7 in the top right hand corner means that the unit is in some kind of "zoom" mode ?? ... otherwise, his transducer is 7ft below the surface !!??
If you measure the height of the "fish", and compare that to the height of the water column ... it would still take 16 "fish", stacked one on top of the other, to equal the 2" height of the portion of the picture representing the water column. Even if the water depth is actually 20.7ft ... it still would take 16 "fish" stacked, to cover the 2" representation of that depth. That would make the fish have to be ~12" tall ... BUT, being as the unit is apparently in zoom mode ... and the fish at an unknown distance away from the transducer ... would it not be a possibility that the size representation of that "fish" could be skewed (by being closer to the transducer than the other objects pictured)???
And, unless Kosmo is 100% certain that he caught that particular fish ... how do we even know if it really is a Crappie ??
But, let's say that the unit IS in zoom mode ... reading a zoomed parameter range of 7-30 feet . The depth is still clearly 20.7 feet ... making the missing top 7ft approx. 1/3 of the equation. Now, remove 1/3 of the supposed 12" height of the "fish" ... and the fish is now 8" tall. That's still quite large for a Crappie !! Our state record Crappie was 18" "around" ... and weighed close to 5lbs !! SO ... let's say the zoom factor is +2x ... making the "fish" closer to 4" tall. See where this is all going ?? This is a flat picture, representing a 3D image ... so it's not going to be easily measured against the other dimensions, without knowing distances from the signal initiation point (transducer).
An easy to understand representation of my flawed math explanation, is this .... look at a car in your driveway, from your front door, then extend your hand & point your thumb upwards ... how big does your thumb look, in comparison to the car ?? See what I mean ?? Can you really measure your thumb, by using just the height of the car, without factoring in the distance between eye & thumb, and eye & car ??
Come on, people .... you KNOW that fish isn't 12 inches tall, because if it was ... it would be ~3ft LONG, using those methods of screen measuring. Give props to the unit for showing a reasonably good image of a fish, and to Kosmo for a good screen shot ... and not turn this thread into another "chevy vs ford" debate.
... cp :kewl
No debate here crappiepappy, I’m just hoping it is a chance for us to learn – and I don’t rule myself out from the learning part here. I don’t think that the comparison of your car and thumb to sonar is accurate. Your brain uses the visual reference of what your eyes see and interprets size from that mainly based on past experiences. Sonar measures only distance and can show signal strength. Your thumb would show up on sonar closer and possibly as a stronger sonar signal which is expressed in colors or shading but not size or distance. The screen snapshot that Kosmo posted was with the Upper Range menu set to 7 feet deep and the Lower Range menu set to 30 feet deep. This is not a zoom function so the distances shown by the sonar should be accurate.
My calculations using a more accurate ruler and zooming in on the image this time:
- Overall height of the image = 8 inches.
- Vertical distance displayed in the image: 23 feet [30 feet – 7 = 23] or 276 inches.
- Each physical inch of the image represents 2.875 feet [23 (feet) /8 (inches)] of water distance or 34.5 inches [2.875 x 12].
- 1/10th of an inch represents 3.45 inches of water distance [34.5/10].
- The fish measured 2/10 to 3/10 of an inch in height.
- So the fish was somewhere between 6.9 to 10.35 inches in height [2 x 3.45, 3 x 3.45].
Now, since I was not working from the original image and I was using a ruler to measure things with I could be off a bit due to blurring the image by zooming in on it, but I believe that my calculations are in order. If not, please tell me where I messed up.
If I print the image out, it's 16cm top to bottom. divide that by the amount of feet displayed in the image which is 23, would give you .69cm per foot. I'd agree with the high side of you range for height, but this fish would be between 1 1/2 to 2ft long. It's either a world record crappie, or more likely, a different fish.
http://i.imgur.com/WYz3n.jpg
Maybe a drum :popcorn.
Could also be a few large Bass !! Look at the screen shot in Catfan's thread on "School of LMB on sunken barge @ Ky Lake" ... the zoomed in pics look very similar in shape and size.
Could also be some large Stripers, or even some of those Asian Carp ... depending on what lake he was on.
Suffice it to say, and I believe we can all agree, those fish are probably not Crappie. No disrespect to Kosmo, as they are very good images ... and since they do have the overall shape of a Crappie, it's easy to see how they could have been mistaken for Crappie.
... cp :kewl
heres a picture of some fish that i thought looks kindof kool. not crappie but still looks kool
Something else to ponder…
You know what amazes me most about these screen pics? The orientation of the fish to the transducer and therefore surface of the water. Stay with here: when we look at these pictures we are looking at them as if we were looking into an aquarium – from the side. That is not how conventional 2D or down imaging sonar looks at them though; they are looking at them from above. So while we see the side of the fish (if he is swimming normally), the sonar sees only the top of the fish. Try this: take your wallet and hold it up in front so that you can see the side of it. That is what you see looking into an aquarium. Now hold it so that you are looking down at it but hold it so that you can only see an edge. This is what the sonar should be seeing. Look at the picture that we have been discussing or even the School of LM Bass picture. Looks like we are looking into an aquarium doesn’t it? So doesn’t that mean that these fish were at least partially turned on their sides?
Now the last picture that Kosmo posted (should have grabbed a screen snapshot Kosmo, it would have been clearer!). This is a Di image from the Side Imaging sonar beams. These may be hitting the fish from the sides, due to being pointed at an angle, and so seeing the profile of the fish should happen more often.