So we have enable both INS_LOG_ BAT_MASK =1 and INS_LOG_BAT_OPT = 2 for post filter checking?
By default it was enabled 3 only…can you suggest what parameter I have to set for throttle based notch .
Just set it to 0
More words
Hello. @andyp1per @xfacta 
I need your help setting up a notch filter. Please see my graphs and logs. Did I do everything right?
This is an Octocopter x8, three-bladed 15 propellers, weight without payload 8kg.
I set the main frequency to 76 Hz.
I’m confused by the peak at 26 Hz
It seems to me that the frequency of 26 Hz is the resonance of the frame, and I installed a static filter.
Thank you in advance for any help. 
Logs:
https://drive.google.com/folderview?id=1R19xJ60X5NYKcJPvGpnCJ_fHo7lunK0i
Before
After
After + static filter 26Hz
sorry i was just miscommunicated the parameter i said INS_HNTCH_OPTS = zero only ,instead i conveyed INS_HNTCH_HMNCS = 3.
Thanks for @dkemxr helping on correction that INS_LOG_BAT_MASK = 1.
this is my post filter graph.@andyp1per is this ok.
More like 71Hz.
25Hz is down in your control bandwidth - be careful about filtering there. There are some notch update artifacts that manifest at 25Hz so that also might be it - 4.1 is better in this regard
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Thank you for the detailed explanation and recommendations. 
I will do more tests with these frequencies.
Hello, Andy!
I made several test flights at 71Hz, which you recommended to me. Do you think this is a good schedule? Or you can somehow reduce the peaks of the schedule!
Thank you for any help in setting up the filter.
Logs:
https://drive.google.com/folderview?id=1fLmia5wScADvDw8W_1t9FyERtCXNs7ij
INS_HNTCH_ATT, 40
INS_HNTCH_BW, 31
INS_HNTCH_ENABLE, 1
INS_HNTCH_FREQ, 71
INS_HNTCH_HMNCS, 7
INS_HNTCH_MODE, 1
INS_HNTCH_REF, 0.218
INS_HNTCH_ATT, 40
INS_HNTCH_BW, 35
INS_HNTCH_ENABLE, 1
INS_HNTCH_FREQ, 71
INS_HNTCH_HMNCS, 7
INS_HNTCH_MODE, 1
INS_HNTCH_REF, 0.218
INS_HNTCH_ATT, 40
INS_HNTCH_BW, 40
INS_HNTCH_ENABLE, 1
INS_HNTCH_FREQ, 71
INS_HNTCH_HMNCS, 7
INS_HNTCH_MODE, 1
INS_HNTCH_REF, 0.218
Dynamic flight:
INS_HNTCH_ATT, 40
INS_HNTCH_BW, 35
INS_HNTCH_ENABLE, 1
INS_HNTCH_FREQ, 71
INS_HNTCH_HMNCS, 7
INS_HNTCH_MODE, 1
INS_HNTCH_REF, 0.218
Seems like you are hitting it reasonably well. You should see if the 25Hz peak moves at higher throttle. Might be worth putting a narrow static notch there
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Thanks, Andy for the suggestion. I will also run tests at 25 Hz. Andy please tell me. What is the best harmonic notch bandwidth? 35 or 40!? 
Andy, greetings. @andyp1per
I hope I am not distracting you from important matters.
I need your help and advice on setting up the filter.
I got rid of the big vibrations on the drone and now I had to re-tune the filter.
Please take a look at my graphs. Did I choose the correct frequency? The peaks still seem very high.
Thank you in advance and really appreciate your recommendations 
Logs:
https://drive.google.com/folderview?id=1YiUQgQFuU74CL4kiIgxUfpvImhz44PuM
Before:
After:
INS_HNTCH_ATT, 40
INS_HNTCH_BW, 37
INS_HNTCH_ENABLE, 1
INS_HNTCH_FREQ, 74
INS_HNTCH_HMNCS, 7
INS_HNTCH_MODE, 1
INS_HNTCH_REF, 0,232
How big is this copter?
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@andyp1per
This is a 1050mm Octocopter, Tarot X8. Propellers 15 inches, three-bladed.
Weight 8kg, no payload.
So given the size its possible that your first harmonic is at 74/2 although the harmonics are pretty messy given that this is an X8
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@andyp1per
Such disordered harmonics appeared after I set Cube Orange to vibration isolation. To reduce vibrations in the Z axis. The vibrations are now within 6 axes on all three axes. Andy, what do you recommend to smooth out the harmonic peaks?
Greetings, Andy. @andyp1per
I have a question about how the filter works. How do you know if a notch filter is working perfectly?
What should CTUNE N look like?
As I understand it, if the filter frequency is selected correctly and the filter is completely well tuned, then the graph should be like in the first photo.
And if the frequency is not chosen correctly and the filter is poorly tuned, then the graph will be as in the second and third photos.
It turns out that the filter works but not completely, right?
Tell me please, Andy, how should the ideal CTUNE N graph and filter work look like?
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You can only tell whether the filter is working well by looking at an FFT - CTUN.N will tell you what frequency was selected, not how effective that selection was.
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Thanks Andy for the explanation. Now I understand.
While flying with various payload weight I have noticed the vibration frequency changes slightly(the heavier the payload and more rotor RPM the higher the frequency).
Is there any way to setup harmonic notch filter so it covers all the different payload weight frequencies?
If you are using the throttle based dynamic notch filter it tracks, but it is sometimes a bit off
Use telemetry ESCs for full tracking of the RPM frequency, or use the FFT option.
Both are available on the ArduCopter 4.1 release.