Problem with source localization using bvef files

Dear all,
I am trying to do the source localization using MNE.
We are using the brain vision product for EEG recording. The location file (*.bvef) is read into MNE-python successfully. But I don’t know how to get the fiducials. Does anyone have dealt with this kind of thing before? I know it’s a little stupid. Should I manually edit the fiducials in the object? Or should I load one EASY-M1 template and modify it to adjust our CAP?
Thank you very much!!!

Do you have individual MRI scans though? If not, I’d say you can simply use the standard_1005 montage, which will work for doing source localization with the fsaverage brain.

Best wishes,
Richard

I do have individual MRI scans and I already used the freesurfer to “recon -all”.

Then I am stucked for the coreg step.

Chao

Thank you again for your response.

Basically, I could not generate the digitization source file from MNE to perform the Coreg.

Could you please tell me if you know how I could continue?

Chao

Could you share one of your EEG recordings and the BVEF file m? Then I might be able to take a look at this if I find a few minutes.

Thank you so much.
I have attached the BVEF file with this reply.

Dear Stefan,
Sorry for the late response.
I compared the default EASYCAP-M1 montage and the electrode location file I was using. I think the fiducials/landmarks for the similar type (same company, similar distribution) could be estimated by the size of the cap. I tried this on EASYCAP-M1.txt in the system. It worked. I am repeating this on my EASPCAP 64 channel.

I got a new problem.
I generated the mne.channels.DigMontage with fiducial and loaded into the coreg GUI. The fiducial landmark could be fitted with MRI fiducials, but the location of the electrode is not showing, which is odd.
Could you tell me if I did something wrong?

Thank you!!

Update on my problem
I set the montage with the EEG file. Then the electrode showed up in the coreg GUI.
Although I am not sure the lpa, rpa, nasion are correct, I think the procedure is through. Please let me know if any of you have questions about my procedure.
Thank you!!

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