Zigzag artefacts in motion corrected data

[Knutsi]

Hi there. We recently came across an issue where NoRMCorre corrupts the output data in odd ways. We have used the library successfully for a long time, and experience the problem only with data from a new 2-photon microscope (Scanimage). The issue appears in some recordings, but not all. We are wondering if this is a known issue, and in any case if there is a fix?

Issue:

• Average image before NoRMCorre
• Average image after
• Raw data
• Parameters

Tried:

• Shifting values to above 0, and ensuring format is uint16
• Removing extreme values (helps, but zig-zag artefact is still present)

Vh Knut Åbjørsbråten

[EricThomson]

I know this is a VERY old issue (apologies). I recently talked to someone who had some issues with artifacts introduced during motion correction using caiman-matlab (which isn't actively supported). If this happens in caiman (python version, which is actively supported), I would consider this a critical bug. I'd be curious if this happens in caiman this would be very bad and we would want to know.