Polar Plot vs Signograph

[Joe in Atlanta]

OK,

I just upgraded to the V3i and have a question. After looking at the post here and other places, I am still confused over what the polar plot does that the Signograph does not. The I under stand the signograph since I used the V3 for a year.

Anyone?

Thanks

[CyberSage]

I am using the 1.1 firmware, so I am not familiar with the polar plot. The analyze modes in my opinion are largely Ineffective on targets deeper than 5 inches, throw in a little trash and all you have is a mess on the screen. The 3 frequency pinpoint gives you better information. I am sure there is someone who can answer your question that has experience with the Polar Plot.

Jack

[russellt]

i thought i would really like that feature .. but it was not to be ...i use the spectrograph to see what freq is hitting the hardest...

[Lowjiber]

When my Vision was upgraded to the V3i, I experimented with the polar plot a bit. I don't really see any advantage to using it over the old Cartesian plot.

I had become so accustomed to the older plot when it came to recognizing pulltabs (for example) that the polar plot quickly slid from my area of consideration. Additionally, I can see multiple coins with a single sweep using the Cartesian plot.

Perhaps others may differ. If so, please help us out.

[rcsnake]

The polar plot is very useful for bottle-caps that are shallow (5 to 6 inches up depending on the ground. The vectors that are being shown are not the normalized vectors. Another way to think about this is for the unnormalized VDI numbers in polar plot form. Hence with the 22.5kHz the high conductive targets (quarter) will be shown toward the X axis as in unnormalized with a VDI of 90-91, while 7.5kHz will above this with the 22.5kHz line with a VDI of 83 and finally with 2.5kHz the line will be above both 22.kHz and the 7.5kHz line and the unormalized for the 2.5kHz should be around a VDI would 67.

Iron has a tendency show a loop from the 2nd quadrant (top left square of graph) to the first quadrant (top right square of graph) when iron is swept over by the coil. Hence, the loops shown on the graph. and this is what I use the polar plot. The loops on the graph shows the phase angle or VDI number changing as the coil is swept over the target as this is typical on some iron targets.

If you think in terms of VDI numbers instead of phase angle of the target then the top middle edge of the screen would a VDI of 0, far right middle edge of the screen would be +95 and then far left middle edge of the screen would be -95 (these would be on the lines or the axis that is formed on the screen.. The rest of the numbers would form a semi circle to complete the VDI numbers on top and then the lines would point to the VDI number.

I might only use this a couple times to help verify a bottle cap that is a little hard to tell from the signal strength of the 3 frequencies in pinpoint mode.

Hope this explains some of the use for this screen


rcsnake

[Joe in Atlanta]

I may have asked this question poorly. I was wonder about the difference between the camel humps and the polar plot. Accoring to RCSNAKE the polar plat identifies iron, the humps do not? Anyone see anything else?

I did notice yesterday that wile using Magic's program and finding silver clad at 4-8 inches, I rarely got good humps. Usually I got nothing on the graph.